Dampness of masonry walls.

One fact peculiar to all kinds of masonry and known to all careful observers is that stone work, brick work, and concrete will allow dampness to permeate, whether it comes from water-bearing soil or a driving rain. One objection to concrete-block houses has been that a hard rain would cause moisture to form on the inside. Brick buildings have the same defect when the walls are built solid.

An air-space in the cellar walls is the only way of insuring a dry cellar, if the bottom of the cellar is below the level of the ground water. A four-inch course of hollow brick may be used on the inside, or the wall may be actually divided into two walls with a space between.



Figure 7 (after Warth) shows three different ways by which an air-space is secured and the two component parts of the wall held together. In the top view, the two walls, one eight-inch and one four-inch, are held together by wire ties, leaving an air-space of about four inches. In the middle drawing the walls are tied together by making the air-space three inches wide and then lapping the brick laid as headers over both walls. In the bottom view special terra-cotta blocks are used which pass through both walls. There can be no question of the value of such construction in eliminating dampness from the inside wall, but, it must be admitted, the cost of the walls is increased somewhat.

Use of tar or asphalt on the wall.

Instead of an open space, nowadays, it is more customary to thoroughly plaster the outside of the cellar wall, and then paint it with a tar paint put on hot, which will adhere fairly well to the cement or masonry. Asphalt cannot be very readily used for this purpose unless it is an asphalt oil with but little bitumen paste. A paving asphalt, for example, even applied hot, does not adhere to the masonry, but slides down the walls as fast as it is applied. A successful method, however, of using such asphalt is to build the cellar wall in two parts, separated about half an inch, and filling in the intervening space with liquid asphalt. In this way, the asphalt is held in position, and is an absolute prevention of dampness.

Another method used successfully in the construction of one of the large railroad stations in Boston consists in painting the outside of the wall with tar and then pressing into the hot tar several layers of tar paper, the separate sheets overlapping in a special coating of tar. These sheets are thus made continuous around the building and under the basement so that no water can enter the building.



A cross-section of one of the depressed tracks entering the Boston Station is shown in Fig. 8. The heavy black line represents ten thicknesses of tar paper, each one thoroughly painted with a thick paint of hot tar. It should be noticed that this water-tight coating is inclosed between masonry walls, so that the coating cannot be injured.

It is possible theoretically by these methods to build an underground cellar so truly water-tight that it could be set down in a lake, where it might float like a boat and not leak a drop, and there may be some locations that require such construction, such as a low river valley or an old salt marsh or a city flat, where no adequate drainage is provided. But practically such construction will always be found expensive, and is, in most cases, unnecessary and ineffective, as already indicated, and where the percolating water cannot be tolerated, involves the installation of some kind of pump to throw out the water that will inevitably, in larger or small quantities, pass through the best water-proofing. It is, therefore, the part of wisdom to place reliance on draining the water away from the house rather than on water-proofing the cellar wall.

Dry masonry for cellar walls.

It may not be out of place to add a word of caution against the practice of building cellar walls of loose stone, without mortar. They make no pretense of being water-tight, they offer no resistance to the entrance of rats, and they soon yield to the pressure of the earth and present that wobbly, uncertain appearance of cellar walls seen in rural districts. Nor should the idea that the interior is to be visible and the exterior invisible blind the builder to the fact that it is far more important to have the outside smooth. If smooth, there are no projecting surfaces for water to collect in, no edges for the frozen earth to cling to and by expansion tear off from the wall. If smooth, the joints in the masonry can be pointed or filled with mortar, and thus a suitable surface for the tar or asphalt is provided.



In Fig. 9 (after Brown) is shown a cellar wall with rough, irregular back, and it is easy to see how water would readily find its way down to one of the projecting stones and then along such a stone, through the wall into the cellar. With such a wall the action of the frost is more severe than with a wall with a smooth back, so that the wall in Fig. 9 is gradually pulled apart by alternate freezings and thawings. Figure 10 (after Brown), on the other hand, shows the cellar wall as it should be with smooth, even exterior, along which the water passes easily, with gravel backing, through which the water escapes to the drainpipe.



Damp courses in walls.



Another important means of keeping moisture from the cellar walls is to provide what is called a damp course at about a level with the top of the cellar floor. Where the soil is naturally damp, and where the cellar wells are not adequately water-proof, a second damp course should be provided at the level of the ground so that moisture from the damp cellar walls may not pass up into the above ground portion, which is naturally dry. These damp courses, in their simplest form, consist in bringing the masonry level around the building, and painting the top surface with liquid coal tar.



Another method is to paint the masonry with liquid asphalt, and then imbed in this paint a thickness of asphalt-covered building paper which is again painted with asphalt. This may be done in the horizontal layer where it could not conveniently be done vertically.

Four different ways used in France for securing dry cellar walls are shown in Fig. 11. The heavy black line represents the damp course, which, when added to the effect of the interwall space, which is shown in all the drawings but the first, and there replaced by a deep drain, insures absolute freedom from all moisture within the cellar. Figure 12 shows sections recommended by Dr. George M. Price, and indicates clearly the location of the damp course.

The cellar floor.

The floor of the cellar, in the same way, must be kept from dampness, and this is best done by covering the cellar floor with a layer of concrete, one part cement, three parts sand, and six parts broken stone; or, one part cement and eight parts gravel may be used. Care should be taken, however, that the gravel does not contain an excess of sand, and it is always well in using gravel for concrete to check the proportion of these two materials. This may be done as follows: Sift the gravel through an ash sieve so that it is free from sand; fill a ten-quart pail even full with the gravel and then pour in water to the top of the pail, keeping account of the amount of water poured in. This volume of water gives the proper amount of sand to use with the gravel for concrete, and if more sand than this was present in the original gravel, it should be sifted out until the proper proportion is reached.

Concrete is not water-tight, and the concrete floor of the cellar must be treated in some way to prevent water or moisture rising through this floor. One method is to cover the concrete thus laid with a denser mixture of cement and sand, put on three fourths of an inch thick, and made by mixing equal parts of sand and cement; or the asphalt layer already referred to in the cellar walls may be carried across the cellar, putting, as before, a paint layer on the concrete, then paper, then another paint layer, making it continuous and without a break from outside to outside. On top of this, to prevent wear and tear, a floor of brick, laid flat, or a two-inch layer of concrete may be laid.

Cellar ventilation.

The great importance of the cellar as that part of the house where, if anywhere, unhealthy conditions exist, justifies this prolonged discussion, and before leaving the subject, ventilation in the cellar should receive a word of encouragement. Too many cellars are damper than need be, are musty and close, full of odors of decaying vegetables and rotting wood, entirely from lack of ventilation. The cellar windows are small and always, closed. The cellar door is seldom opened, and never with the idea of admitting air. The impression on entering such a cellar is of a tomb.

The cellar, even in that part devoted to storing vegetables, needs ventilation as much as the house does, for the cellar air finds its way up into the house, and an unventilated cellar means a house with air deficient in oxygen and overloaded with carbonic acid, a condition which causes pale faces and anaemic bodies. Far better and healthier is it to open all the cellar windows, covering them with coarse netting to keep out animals and with fine netting to keep out insects, and let the disease-killing oxygen and sunlight in. Malaria comes from the cellar, whenever the malarial mosquito can find there a breeding place. The writer has seen many cellars in which mosquitoes were living the year through in entire comfort, utilizing the moisture and warmth of the cellar to enjoy the winter months and up and ready for their mission at the first sign of spring. A cistern in the cellar is objectionable on this account, and if one exists, it should be covered with mosquito netting.

The old-fashioned privy.

Another source of ill-health as well as of temporary discomfort is the typical construction and continued use of an outside closet or privy. The physical shrinking from the use of the ordinary building is most reasonable. As generally constructed, great draughts of air (presumably for ventilation) are continually passing through the small building, and when the temperature of the outside air is at zero, or thereabouts, only the strongest physique can withstand the exposure involved without serious danger of consumption, influenza, and pneumonia, or at least inviting those diseases by reducing the vitality of the body. Two improvements suggest themselves and should be put into effect wherever this primitive construction must continue to be used.

In the first place, the building itself should not be fifty or a hundred feet away from the house, so that every one is exposed to rain, snow, slush, and ice in making the journey thither. But some corner of the woodshed or barn should be utilized or the small building should be moved up by the back door and connected therewith by a roofed passage. The barn location is objectionable if it involves outdoor exposure in going from the house to the barn. A liberal use of earth in the privy vault will eliminate odors, and a water-tight box or bucket makes a frequent removal of the night soil practicable.

In the second place, a small stove ought to be provided to warm the closet in the coldest weather. Then the dislike to suffer from the cold, which leads so many to postpone nature's call, will be avoided, and the consequent digestive disorders which come from constipation and intestinal fermentations prevented.

Cow stables.

In matters of health, aside from ventilation, which is discussed in the next chapter, there is little to be said concerning the other buildings on the farm. Barns for hay are not involved. A few words may profitably be devoted to barns for stock, involving, as they do, by their construction, the health of the stock. One enthusiastic farmer writes that it is possible for farmers to keep their stock at all times under conditions which are an improvement upon the month of June. He believes that the cow stable should be as comfortable for the cows as the house is for the owner, subject to no fluctuations of temperature, and that, in this way, the health as well as the comfort and milk production of the cows would be maintained.

Light should be listed as the first essential of healthy stables, light to kill disease-producing bacteria, to make dirty corners and holes impossible, and to react on the vitality of the animals. Compare this with some stables where fifteen, twenty, or thirty head are stabled in an underground dugout with two or three small windows not giving more than four square feet in all. Stable windows should be set, like house windows, in two sashes and capable of being raised or lowered at will. In winter a large sash may be screwed over the regular window to keep out frost and moisture, provided there is some independent method of ventilation.

For good healthy conditions, a cow needs about 500 cubic feet of space, with active ventilation. In old stables, with poor construction, as little as 200 cubic feet per cow was allowed, and when stables were made tight with matched boards and building paper, 200 cubic feet was found to be too small, and it was recommended that one cubic foot be allowed for each pound of cow. But when tried by wealthy amateurs, it was found that this was too large; the stables were damp and cold in winter and became a predisposing factor in the development of tuberculosis. Between the two extremes, 200 and 1000, is the practical average named above, namely, 500 cubic feet of air space for each cow.

For the health of the cow as well as for the good quality of the milk the stable should be built with special reference to being kept clean. The ceiling should be dust-tight, so that if hay is stored above, it will not sift through. The part of the barn where the cows are kept should be separated from the rest of the barn by tight partitions and a door into the cow stable. Nothing dusty or dirty should accumulate. The floor of all stables for cows, horses, hens, and pigs should be of concrete to insure the most sanitary construction. Planks absorb liquids and wear out rapidly under the feet of the stock. Concrete can be kept clean, is nonabsorptive, and if covered with some non-conducting material, like sawdust, shavings, or straw, is a perfectly comfortable floor for the animals.

Use of concrete.

No development of recent times has tended more toward the improvement and greater comfort of house building than the use of concrete. In the earlier houses, the cellar walls were so badly built and the connection between the top of the cellar wall and the timber sill of the house was so poor that the winter's wind blew through above to the manifest discomfort of those in the house. The writer remembers sitting in the best room of a well-to-do farmer, and watching, with great interest, the carpet rise and fall with the gusts of wind outside. To avoid such unhappy consequences, farmers have been accustomed to bank up the house outdoors in the fall with dry leaves, spruce-boughs, or manure, usually to a point on the woodwork. This, of course, closes the cellar windows for the winter for the sake of keeping out the wind. A concrete wall, at the present price of cement, using gravel for the mixture instead of stone, need cost but little more than the price of the cement and the labor involved, and a tight cellar wall may thereby be obtained.

If the soil in which the cellar is dug is firm enough, the outside of the excavation can be made so that no form on that side will be required, but it is always better to make the excavation about two feet more than necessary, to put forms inside and outside, and, after their removal, plaster or wash the wall with a thick cream of cement and water. In carrying the wall above the ground, forms must be used with great care to secure a smooth surface, and Fig. 13 shows two methods suggested by the Atlas Cement Company.



There are so many forms of construction where concrete is not merely a convenience but a great advantage in the matter of health around the house, and particularly a house in the country, that there would be no end if one once began enumerating and describing the various methods and processes involved. Besides the cellar walls and cellar floor, there are outside the house, silos, manure bins, walks, curbing, steps, horse-blocks, hitching and other posts, watering troughs, and drainpipe, all successfully made of this useful material. In the barn, the barn floor, the gutters, the manger and watering troughs, cooling tanks, and sinks are also made of cement. While it is possible to differentiate between the methods and the mixtures for these various purposes, it will not be greatly in error if the construction always follows the following principle.

Use enough cement to fill the voids in the gravel or in the sand and stone mixture employed, and have enough sand in the gravel or with the stone to fill the voids in the stone. This is readily determined, as already suggested, by the use of water. The water, which will occupy the voids in the stone, represents the necessary sand. When this amount of sand and stone is well mixed, the water then permeating the interstices represents the necessary cement, though it is a good plan to add about 10 per cent extra to allow for imperfect mixtures.

The mixing should always be done so thoroughly that when put together dry, no variation can be seen in the color of the mixture. It is surprising to see how readily a streak of unmixed dirt or of unmixed cement can be detected in a pile by the difference in the color which it presents. Such mixtures should always be made dry first and then the water added and again mixed until the result is of a perfectly firm consistency. Such a mixture can be applied to any of the purposes mentioned, and, in general, it is better to have too much water than not enough. The only difficulty with a very wet mixture is that the forms require to be made nearly water-tight, whereas with dry mixtures the same attention to the forms is not necessary.

If the concrete is to be used in thin layers, as in pipe or watering trough, where a smooth surface is wanted, better results are usually obtained by using a dry mixture and fine gravel and tamping the mixture with unusual thoroughness. It is always unsafe to smooth up or re-surface a piece of concrete. The difference in texture of the surface coat causes it to expand and contract differently from the mass of concrete underneath, and inevitably a separation occurs. If it is desired to put on a sidewalk, for instance, a smooth top coat, the consistency of the two kinds of concrete should be alike, and the top coat should be applied almost immediately after the bottom layer is put in place. Where concrete is used to hold water, a coat of neat cement should always be put on with a broom or a whitewash brush, mixing the neat cement with water in a pail, and it does no harm to go over the surface three or four times, the object being to thoroughly close the pores in the concrete.

For floors of cellars or barns, the dirt should be evened off and tamped and then the cement concrete should be spread evenly over it, and tamped just enough to bring the water to the surface. When partially dry, a better finish is obtained by lightly troweling the concrete. In a cellar or barn, it is not necessary to divide up the area into squares or blocks as is done with sidewalk work, but the entire area may be laid in one piece. In order to keep the surface level, however, it may be found convenient to lay down pieces of 2" x 4" scantling, the tops of which shall be on the desired level of the finished floor. By filling in behind these scantlings, which can be moved ahead as the filling progresses, the exact level desired can be obtained. Usually four inches thick will be a proper depth of concrete for this purpose.



CHAPTER IV

VENTILATION

The average individual breathes in and out about eighteen times a minute, taking into his lungs the air surrounding him at the time and expelling air so modified as to contain large amounts of carbonic acid, organic vapor, and other waste products of the lungs. The volume of air taken in is about the same quantity as that expelled and amounts to eighteen cubic feet per hour. Fortunately, the air expired at a breath is at once rapidly diffused throughout the surrounding atmosphere, so that, even if no fresh air were introduced, the second breath inhaled would not be very different from the first. But after a certain length of time the air becomes so saturated with the waste products of the lungs that it is no longer fit to breathe, and it is evident that in order to keep the air in a room so that it can be taken into the lungs with any reasonable degree of comfort, there must be a continual supply of fresh air admitted with a proper provision for discharging polluted air. If this is not done, there is, so far as the lungs are concerned, a process established similar to that which is occasionally found when a village takes its water-supply from a pond and discharges its sewage into the same pond.

Not long ago, the writer found in the Adirondacks a hotel built on the side of a small lake which pumped its water-supply from the lake, and discharged its sewage into the same lake only a few feet away from the water intake. That the hotel had a reputation of being unhealthy, and that it had difficulty in filling its guest rooms, is not to be wondered at, and yet individuals will treat their lungs exactly as the hotel treated its patrons.

Effects of bad air.

In order to establish a proper relation between the amount of impurities diffused through the air and the physiological effect on individuals breathing that air, certain observations have been noted and certain experiments have been made which prove without question the injurious effect of vitiated air.

Professor Jacob, late Professor of Pathology, Yorkshire College, Leeds, gives the following example on a large scale, to show the results of insufficient ventilation: "A great politician was expected to make an important speech. As there was no room of sufficient dimensions available in the town, a large courtyard, surrounded with buildings, was temporarily roofed over, some space being left under the eaves for ventilation. Long before the appointed time several thousand people assembled, and in due course the meeting began; but before the speaker got well into his subject, there arose from the vast multitude a cry for air, numbers of people were fainting, and every one felt oppressed and well-nigh stifled. It was only after some active persons had climbed on the roof and forcibly torn off the boards for a space about twenty feet square that the business of the meeting could be resumed."

Remembering that the process of breathing is for the purpose of supplying oxygen to the blood and that the absorption of oxygen in the lungs is the same process which goes on when a candle burns, the following experiments were made by Professor King of the University of Wisconsin, to show the effect of expired air on a candle flame. He took a two-quart mason jar and lowered a lighted candle to the bottom, noting that the candle burned with scarcely diminished intensity. Through a rubber tube, he breathed gently into the bottom of the jar, with the result that the candle gradually had a reduced flame and was finally extinguished. He observed also that if the candle were raised as the flame showed signs of going out, the brilliancy of the flame was restored, while lowering the candle tended to extinguish the flame. Even when the candle was raised to the top of the jar, the flame was extinguished after sufficient air had been breathed into the jar. Clearly, then, he argued, air once breathed is not suitable for respiration, unless much diluted with pure air. He argued from this that if a candle using oxygen for combustion could not burn in expired air, therefore an individual using oxygen for the renewal of the blood could not be properly supplied in a room partially saturated with the expired products of the lungs.

Professor King also experimented with a candle burning in a jar on which the cover had been placed, and found that the candle was extinguished in thirty seconds, and he argued that if a candle was thus extinguished on account of the carbonic acid given off, so a person shut up in an air-tight chamber would similarly be extinguished in the course of time.

To prove that expired air is poisonous to animal life, Professor King experimented on a hen, placing the same in a cylindrical metal air-tight chamber eighteen inches in diameter and twenty inches deep. The hen became severely distressed for want of ventilation and died at the end of four hours and seventeen minutes.

In the Wisconsin Agricultural Experimental Station, an experiment was conducted for fourteen days on the effect of ample and deficient ventilation on a herd of cows. The stable was chiefly underground and had two large ventilators which could be opened or closed at will. The food eaten, the water drunk, the milk produced, and weight of the cows were recorded each day. For a part of the time the cows were kept continuously in the stable with all openings closed, and then the ventilators were opened, the alternate conditions being repeated at intervals of four days. The amount of food consumed was practically the same under both conditions. The quantity of milk given was greater with good ventilation. The chief difference was in the amount of water consumed, since with the insufficient ventilation the cows drank on the average 11.4 pounds more water each, daily, and yet lost in weight 10.7 pounds at the end of each two-day period. Examination of the animals themselves also showed that a rash had developed on their bodies which could be felt by the hand and which was apparently very irritating, since it was so rubbed by the animals as to cause the surface to bleed. The evident teaching of the experiment is that under conditions of poor ventilation, it was impossible for the lungs to remove waste products to as great an extent as usual, and, therefore, the demand for additional water was felt in order to stimulate greater action on the part of the kidneys to care for these waste products. That this was not a successful substitute was shown by the loss of weight in the animals, and by the irritation of the skin which evidently was trying to eliminate some of the remaining impurities through its surface.

Modifying circumstances.

Fortunately for mankind, it has not been customary, nor even possible, to build dwellings or stables approaching the air-tightness of a fruit jar. Air has great power of penetration, particularly when in motion, and a wind will blow air through wooden walls, and even through brick walls, in considerable quantity. It is practically impossible to build window casings and door frames so that cracks do not exist, through which air may find its way. When, however, in the wintertime, storm windows have been put on, or when, as occasionally happens, to keep out drafts, strips of paper are pasted carefully around all window casings, or when rubber weather strips are nailed tight against the windows and doors, conditions are obtained which resemble the mason fruit jar, and under those conditions, a person living continuously in such a room is experimenting on himself as Professor King did with the candle.

Another reason why it is difficult to make a room an air-tight chamber is that if a stove or fire-place be in the room, a strong suction is produced through the flame, and such suction requires the entrance of outside air. It is a common experience that a fire-place in a room otherwise tight will refuse to draw and will smoke persistently until a door or window is opened, when, a supply of air being provided, the fire is made bright and active.

Fortunately, the vitiation of the air in a room is never so severe as that in an experimental chamber, and there are few examples which can be cited of men or women dying from lack of ventilation in an ordinary room. But the serious aspect of inadequate ventilation is not that it actually induces death, but that it decreases the powers and activities of the various organs of the body; that it interferes with their normal processes, that it loads up in the body an accumulation of organic matter which is normally oxidized by fresh air and which, if not oxidized, obstructs the activities of other organs of the body.

Danger of polluted air.

Unfortunately, it is not possible to detect by the physical senses that point at which the human organism suffers from insufficient ventilation. Some years ago, Dr. Angus Smith built an air-tight chamber or box in which he allowed himself to be shut up for various lengths of time in order to analyze his own sensations on breathing vitiated air. He found that, far from being disagreeable, the sensation was pleasurable, and he says, "There was unusual delight in the mere act of breathing," although he had remained in the chamber nearly two hours. On another occasion he stayed in more than two hours without apparent discomfort, although after opening the door, persons entering from the outside found the atmosphere intolerable. He placed candles in the box, which were extinguished in a hundred and fifty minutes, and a young lady, who was interested in the experiment, going into the box as the candles went out, breathed it for five minutes easily; she then became white, and could not come out without help.

Nor is it possible to conclude from the experiments and observations cited that the body remains indifferent to polluted air until the latter has reached a certain definite saturated condition. There can be little doubt but that a degree of pollution far short of that necessary to produce death has a weakening effect on the human organism, and that by means of the increased functional activity of other organs doing work intended for the lungs the resistance to disease is much impaired. Life is a continual struggle of the bodily tissues against the attacks of the micro-organisms and their tendencies to destroy life; hence inadequate ventilation or any other condition which interferes with the normal action of the organs of the body causes weakness and affords opportunity for the attack of some disease-producing germ. It stands to reason that an individual whose lung tissues have become soft and incapacitated must be more liable to succumb to disease than another whose lung capacity is large and whose blood has been continually and sufficiently oxygenated.

Perhaps no more impressive proof of this is seen than in the ravages of consumption, which is so prone to attack those whose vitality is diminished by living in unhealthy and unventilated cellars or in crowded tenements. Statistics are very definite on the subject of tuberculosis among Indians, who rarely suffer from the disease when living in tents or on the open prairie, but when they become semi-civilized and crowd together in houses heated through the winter months by stoves, the germs of tuberculosis take firm hold, and the deaths from this disease are greater in proportion to population among this race than anywhere else.

Effect of change in air.

This discussion illustrates another law of disease which makes the necessity for ventilation particularly great among rural communities where for nine months in the year outdoor life is freely enjoyed, namely, that when either an individual or people are brought under changed conditions, perhaps not unwholesome to those accustomed to them, those unaccustomed will suffer severely. So a lack of ventilation during the winter months in a farmhouse is very serious in its consequences to those who have had the full enjoyment of fresh air through the rest of the year.

Reference has already been made (in Chapter 1) to the prevalence of influenza in rural communities, and it is quite probable that this would be largely eliminated if the lungs were not deprived of their oxygen as they are in most houses on the farm.

Composition of air.

Ordinary air contains about 0.04 per cent of carbon dioxid; that is, four parts in ten thousand parts of air, the other nine thousand nine hundred ninety-six being made up of oxygen and nitrogen. Of course, it is not possible to express any definite value for the amount of carbon dioxid which is objectionable in air, because, in the first place, it is not certain that the carbon dioxid in itself is the cause of diminished vitality due to insufficient ventilation, and, in the next place, insufficient ventilation affects different people in different ways. But it is known that in the lungs the life-giving oxygen is changed to carbon dioxid, and that just as carbon dioxid gas will prevent the combustion of a candle flame, so carbon dioxid gas will destroy the life of man.

When a deep well is to be cleaned out, the decomposition of organic matter in the bottom of the well will have, in all probability, caused the formation of this same carbon dioxid gas, and it is not uncommon for a man descending into such a well to be overcome by the gas, which, in some cases, even causes death. For this reason, it is common to lower into a well, before it is entered by a man, a candle or lantern, on the probability that if the lantern can stand it, certainly the man can, while if the lantern goes out, it is wise to avoid the risk of having a man's life put out in the same way.

Organic matter in air.

The stuffy and close feeling perceived in an ill-ventilated room is, however, due to the organic matter from the lungs, which is expired along with the carbon dioxid, and some chemists have argued that this amount of organic vapor ought to be measured instead of the carbon dioxid.

At the present time there is no simple and direct method of measuring organic vapor, and because this vapor increases in the atmosphere proportionately to the carbon dioxid gas, it is much simpler to measure the latter. Then it is impossible to fix a standard of carbon dioxid because a person whose lungs are well developed and whose blood is well oxygenated, or, as we say, one who has good red blood can stand, even if uncomfortable, a few hours of a bad atmosphere without suffering serious discomfort, while an anaemic or poor-blooded person would be affected to a greater degree. It is for this reason that in any house no living room, especially one heated by a coal stove, should be shut up tight against fresh air. This is the reason why the women of the family, who have to breathe the same air over and over all day, are pale and weak and easily susceptible to disease, while the men, who are out of doors most of the time, and when indoors are made restless by the bad air, suffer much less from the ill effects.

Experiments seem to show that when the amount of carbon dioxid in the air has doubled, that is, when the expired air mixed with the air in the room has increased the proportion of carbon acid from four parts in ten thousand to eight parts in ten thousand, that the air is seriously affected, and that such ventilation ought to be provided that no greater amount than this could occur. This is such a condition that the room smells "close" or stuffy to a person coming in from outdoors, indicating organic emanations as well as an excess of carbonic acid gas. The question then is: how may this condition be avoided in an ordinary house, or in an ordinary stable, because the health of the cattle on a farm, judging at least by the character of the buildings provided, is quite as important as the health of the farmer's family.

We must take it for granted that no such elaborate schemes are possible as in public buildings or schools, where fans are provided, either to force air into the several rooms or else to suck it out. The ventilation of the house must be more simple and easily adjusted and must depend on the principle of physics that warm air rises and that if the warm air of a room is to be removed, air must in some way be supplied to take its place. The two essentials for ventilation are opportunity for the ingress and the egress of air—ingress for fresh air and egress for polluted air.

Fresh-air inlet.

In the construction, of a dwelling house, special and adequate preparation for the admission of fresh air is seldom provided, so that the existing openings must be used for the purpose. This means that in the summertime an open window will furnish all the fresh air which a room receives and, when the temperature of the outside air is approximately that of the living room, such provision is ample and satisfactory. But in the wintertime, when the outside air is cold, the average person will prefer to suffer from the bad effects of impure air rather than admit cold air which may cause an unpleasant draft.



One of the simplest and best methods of providing an inlet for fresh air, without at the same time allowing blasts of wind to enter the room, is to fasten in front of the lower part of the window a board which shall just fill the window opening; then, raising the lower sash a few inches will allow fresh air to enter both at the bottom, where the board is placed, and at the middle of the window between the sashes (see Fig. 14). Persons sitting close by a window thus arranged may feel a draft even under these conditions, since the cold air thus admitted will sink at once to the floor and then gradually rise through the room to the ceiling, but unless one sits too near the window, this is an admirable method of admitting fresh air.

Another method, where steam or hot-water radiators are placed in the room, is to connect the outer air, either through the lower part of the window or through the wall of the room just below the window opening, with a space back of the radiator, so that the cold air entering will pass around and through the radiator and so be warmed as it enters.



The picture (Fig. 15, after Jacobs) shows the arrangement of the radiators in one of the buildings of the University of Pennsylvania. A is the opening in the wall below the window; D is a valve which regulates the amount of air entering through the opening; R is the radiator; B is a tin-lined box which surrounds the radiator; T is a door in front of the box, which when raised allows the air of the room to be heated and to circulate through the radiator. By adjusting the two valves D and T, air of any desired temperature can usually be obtained. Figure 16 (after Billings) shows an English device intended for the same purpose. The valve D in this case operates to admit air, either through the radiator or to the space between the radiator and the wall, in order to vary the temperature of the entering air. The valve T may be open or closed, and its position, together with that of the valve F, determines the proportion of the room air which is reheated.



The writer remembers one schoolhouse where these methods were used successfully, the radiators being placed directly in front of the window and inclosed at the back, sides, and top, except for an opening to the outer air through the wall, properly controlled by a damper. In the writer's own office the radiators are by the side of the window and are boxed in, the connection being made with the outside air through a wooden box entering under the radiator. This is an admirable method, provided the radiator has sufficient surface to warm the fresh air admitted.

Another excellent arrangement is to provide a narrow screen similar to that used for protection against flies, but with the screening material of muslin cloth instead of wire cloth. This muslin will break up the current of air so completely that no draft is felt by persons sitting even close to the open window.

Position of inlet.

The inlet for fresh air, if connecting directly with the outside air, should not be at the top of the room, since then the inlet would not serve to admit air, but rather to allow the warm air of the room to escape, and a burning match would inevitably show a draft outward instead of inward.

Neither is it desirable to have the fresh-air inlet near the floor of the room unless the entering air is warm, because cold air admitted will flow across the floor and remain there, not disturbing the warm upper layers. The effect then is not to improve the ventilation, but only to chill the feet of persons sitting in the room. The position of the window lends itself, therefore, to admission of fresh air, since it is neither at the top nor at the bottom of the room, but at the level most suitable for such admission.

Foul-air outlet.

Very few houses have any provision for the outlet of spent air, and if ventilation is thought of at all, the only idea usually is to provide, in part at least, for the admission of air and to make no adequate arrangement for its egress. Whenever a stove or fire-place is in use, the mere burning of fuel requires the consumption of air, and in cases where apparently no air is admitted to the room, insensible ventilation is at work bringing into the room, through the walls and through cracks around the doors and windows, the necessary air for combustion.



It may be proved by the laws of physics that a coal stove burning freely in a room causes adequate ventilation; and that only where the dampers of the stove are closed, so that not merely is the supply of fresh air diminished, but also the products of combustion are thrown out into the room, is there danger from lack of ventilation. The stovepipe in this case furnishes the necessary outlet for the impure air, and the following suggestion has been made in order to utilize this outlet, even when the fire is not burning freely or when the damper in the stovepipe is closed. If the stovepipe from a stove is carried horizontally, as it usually is, an elbow must be provided to raise the pipe to the stove hole in the chimney. Then providing a T connection at the point marked A in Fig. 17 (after Billings), the lower part of the T may be carried to within a foot of the floor with a damper at the points B and C. When the fire is burning freely, the damper at C is closed, and ventilation is secured through the stove, the damper at B being open. When the damper at B is closed and the fire checked, then the damper at C may be opened and the impure air drawn up the chimney from the level of the floor. This, it is said, is an effective arrangement for drawing off the polluted air of a room.



Another method is to surround the stove with a sheet-iron casing, as shown in Fig. 18 (after Billings), the top of the casing having a pipe leading into the chimney independently from the stovepipe. The casing becomes warm and heats the room by radiation, just as the stove does, but if the damper in the flue from the casing be opened partly, a strong draft along the floor and into this casing will be developed and the foul air thereby discharged into the chimney. It will be easily possible, of course, to carry away all the heat from the stove in this method, and the damper in the flue of the casing must be carefully regulated to carry away only the desired amount of foul air.



Still another method of using the heat of a stove to secure ventilation is shown in Fig. 19 (after Billings). Here the stove is surrounded with a sheet-iron jacket extending from the floor to about six feet above that level. A pipe is carried from the outside air up through the floor directly under the stove. By regulating the damper in this pipe the supply of fresh warmed air entering the room can be regulated. Doors in the casing must, of course, be provided for the purpose of taking care of the fire, and of allowing air from the room near the floor to be heated instead of the outside air.

A most objectionable method of providing an outlet for polluted air from a room is to have a register in the ceiling with the ostensible purpose of warming the room above. It was the writer's misfortune once to stay a week in the country, in a room over the kitchen where this method of heating was employed, and the odors of cabbage, onions, and codfish which permeated the upper room, and clung there all night, still remain as a most unpleasant memory.

Size of openings for fresh air.

As an indication of the size of the openings needed, it has been said that in order to provide the necessary air movement, and yet to restrict the velocity of the moving air so that no objectionable drafts will be experienced, at least twenty-four square inches sectional area should be allowed as an inlet for each person, so that one square foot is required for six persons. This is, perhaps, a theoretical requirement. Certainly, it is more area than is likely to be obtained in actual ventilation. The space between two windows, for instance, is about one inch by thirty inches,—barely enough, according to this rule, for one person, and yet that opening is sufficient to appreciably improve the quality of the air in a room occupied by three or four persons.

Taking into account the necessary air required by lamps or gas burners, the inlet flue should have at least ten square inches area for each person, so that the ordinary single register should provide the necessary amount of air for a living room. When, as happens in houses where a studied effort is made to preserve the health of the inhabitants, an outlet is cut into the wall and a flue carried up through the roof, the flue should be preferably near the floor and on the side of the room opposite the window or inlet. With such an arrangement (see Fig. 20) the air entering rises at first, but sinks at once because of the temperature, so that the direction of the air currents are diagonally across the room from the ceiling to the floor, thus renewing and changing all the air particles except those directly over the outlet. Where the air is introduced mechanically, that is, forced into the room, it is better to have the inlet and outlet on the same side, so that the entering air is shot in at the top, flowing across the room, then sinking and coming back, just below the point where it entered.



Ventilation of stables.

All that has been said on the subject of ventilation in houses applies equally well to the ventilation of stables, and a little book by Professor King of the University of Wisconsin, entitled "Ventilation," deals most thoroughly with the principles and practices of ventilation, not merely for dwellings but also for stables. Professor King proves by his experiments that the condition of cattle is much improved and that the milk-giving qualities are increased by a proper supply of fresh air, and in the book referred to, he gives a number of examples of the proper construction to provide adequate ventilation. It is most convincing to see how unscientific is the old-fashioned underground stable, the sole idea of which was to conserve the animal heat by crowding together the cows and by absolutely excluding the outside air. For further details of his work, its principles and practices, the reader is referred to the book, which may be obtained from the author at Madison, Wisconsin.

Cost of ventilation.

To ventilate a house is expensive, and to ventilate a barn requires not only a certain expenditure of money but also a considerable amount of judgment. It is evidently cheaper to heat the same air in a room over and over than to be continually admitting cold fresh air, which will have to be warmed. This extra cost is, however, not excessive, when the movement of the air currents is properly controlled. The cost of warming the air necessary for ventilation for five persons should not be, at the rate of 1000 cubic feet of air to each person, more than ten cents a day in zero weather, with coal at five dollars a ton. Enough coal will have to be burned in addition to compensate for radiation, or, in other words, it requires a certain amount of coal to keep an empty room warm in winter without any question of ventilation, and in some badly built houses this amount is large.

Relation of heating to ventilation.

It does not follow because much heat is lost in this way that the ventilation is good, since the heated air may ascend to the ceiling and there escape without influencing the ventilation. In fact, one of the first principles of ventilation is that as soon as regular inlets and outlets are provided, all other openings ought to be rigidly closed. Then and then only can the warmed pure air be admitted as desired, at the points intended, and the full value of the heat utilized. Especially is this control of openings important in ventilating barns. Here each animal is a natural heater, warming the air by direct contact and by rapidly breathing in and out large volumes of air which are thereby changed to a temperature of over ninety degrees Fahrenheit. The air around their bodies being warmed rises to the ceiling and spreads out to the two sides and is there gradually cooled and at the same time mixed with fresh air which enters at the top, so that the cow is constantly supplied with freshened air. A flue is needed to carry the foul air up through the roof, and fresh-air inlets in the outer walls on both sides are required, and with these openings carefully controlled and with no others interfering, the stable may be well ventilated, as shown in Fig. 21 (after King).



In all cases where ventilation is to be practiced, the walls and ceiling should not merely be tight in themselves, but they should be double, and the strictest attention paid to limiting the amount of heat lost by radiation. All the heat used ought to be concerned in ventilation, and in that only. To secure air-tight walls and ceiling, the studding and joists should be boarded in, both on the inside and out, and the space between should be filled with shavings, straw, dry moss, or any similar fibrous substance. The outside sheathing must be well laid and must be water-tight in order that rain shall not penetrate to the inside of the wall, and the roof must be tight so that the ceiling filling does not get wet and rot.

The choice, therefore, so far as ventilation of either house or barn goes, lies between a poorly built, loose-jointed structure without artificial ventilation and with poor economy in heat, and a well-built, air-tight structure, with ample ventilating pipes, carefully and intelligently planned and built. The first is healthy so far as pure air is concerned, but drafty and uncomfortable. The second is more expensive to build, but insures lasting health and comfort. Then the choice cannot but fall on the building which is easy to warm, healthful to live in, and readily ventilated.



CHAPTER V

QUANTITY OF WATER REQUIRED FOR DOMESTIC USE

Until the last few years it has been a sad commentary on the intelligence of the average farmer that but few attempts have been made to supply the farmhouse with running water, adequate to the needs of domestic use. The men of the farm long ago realized that carrying water for stock in pails was both laborious and time-consuming, and very few barnyards have not had running water leading into a trough to supply the needs of cattle. In many cases this supply has been extended into the barn, and in some cases into individual stalls, so that the farmer has long since eliminated the necessity of hauling water for his stock. Perhaps, because the farmer did not himself carry the water, but rather his wife, he has until recently not concerned himself with any extension of the water-supply into the house, and so long as the well in the yard did not run dry, he felt that his duty had been done. To be sure, bringing water from the well to the house in mid-winter involves much exposure and sometimes real suffering; occasionally the farmer has been moved on this account to have the well located in the woodshed or on the back stoop, avoiding the long outdoor trip, but increasing the dangers of pollution to the water. It would be interesting to make a census of the farm water-supplies in any county for the purpose of estimating the intelligence of the farm-owners, since one cannot but feel that such a primitive water-supply argues, in most cases, an undeveloped or one-sided intelligence on the part of the property owner.

Modern tendencies.

Happily, such primitive methods of bringing water to the house are being superseded by satisfactory installations, and one by one, each farmhouse is being provided with running water in the kitchen sink and with a bath-room containing all the modern conveniences. One cannot deny that this costs money, both because of the pipe line necessary to bring the water to the house and because of the plumbing fixtures required in the house. Again, a water-supply in the house involves a well-heated house, since pipes not kept warm will, in the winter, inevitably freeze, ruining the pipe line and perhaps the ceilings and walls of the house itself. But if the owner of a house has any money to expend in improvements, surely no better way of adding to the comfort and health of his family can be found. An abundant supply of water increases the self-respect of the whole family and has been known even to change the temper of an entire household. For another reason, also, it is a good investment, inasmuch as the quality of the water supplied from a spring on a hillside is, generally speaking, better than that of a well surrounded by barnyards and privies.

It has been said that the civilization of a community is measured by the amount of soap that it consumes, and it is almost the same thing to say that the refinement of a household is measured by the amount of water it uses. The poorer a family, the greater struggle it is to keep up the appearance of cleanliness, and no surer sign of rapid progress on a downhill road can be found than neglect of those practices which tend toward personal neatness. As the life of the farmer, then, becomes easier, as his condition becomes more prosperous, and as his family make more requirements, so, inevitably, is there in the farmhouse a greater demand for water in the kitchen, in the laundry, and in the bath-room.

Quantity of water needed per person.

Just how much water is needed in any house is not easy to predict, unless, at the same time, it is known, not merely the present habits of the family, but also their capacity to respond to the refining influence of unlimited water.

It has been shown by measuring the amount of water used in families of different social standing in cities of New England that the amount of water varies directly with the habits and social usages of the family. For example, in Newton, Massachusetts, where there are a large number of small houses with the water-supply limited to a single faucet, it was found that the water used amounted to seven gallons per day for each person in the house, while in houses supplied with all modern conveniences, the consumption of water was at the rate of twenty-seven gallons per day for each person. In Fall River, the conditions were much the same except that the poorer houses generally had one bath-tub and one water-closet, the amount of water used being eight and a half gallons per head per day, while the most expensive house in the city used twenty-six gallons per head per day. In Boston, the poorest class apartment houses used water at the rate of seventeen gallons per head per day, the moderate class apartment houses at the rate of thirty-two gallons, first-class apartment houses at the rate of forty-six gallons, and the highest class apartment houses at the rate of fifty-nine gallons per head per day. The difference in these rates is easily understood by considering the habits of the individuals who make up the different classes referred to. In the poorer class of houses, the workers of the family are gone all day, and are too tired when home to spend much time in bathing. The children of such households are washed only occasionally, and the external use of water is generally regarded as an unnecessary trouble. In those families, on the other hand, where the necessity for daily toil is not so pressing, where bathing is more frequent, and where ablutions during the day are more often repeated, the amount of water used is much larger.

Another factor that affects the measured amount of water used in a family is the number of plumbing fixtures. At first sight, it would not seem possible that because there were two wash-basins in a house, an individual should use more water than if there were only one basin. Nor would it seem possible that an individual would take more baths with three bath-rooms available than if only one existed, and yet the number of fixtures does influence the individual who washes his hands frequently. With a wash-basin on the same floor, for instance, he washes often, whereas if it were always necessary to go upstairs for the purpose, his hands would go unwashed. Also, the more fixtures there are, the greater is the amount of leakage, since every faucet will, in the course of time, begin to leak unless the packing is continually replaced. The amount of leakage is, therefore, in direct proportion to the number of fixtures.

The amount of water used then, per head per day, varies from seven to sixty gallons, but only by an intimate knowledge of the habits of the household can one predict the amount of water likely to be used. Perhaps as an average in a house having a kitchen sink and a bath-room containing a wash-basin, bath-tub, and water-closet, a fair estimate of the water used would be twenty-five gallons per head per day. This amount must be multiplied by a maximum number of persons to be in the house at any time, and then this number must be increased by the amount of water used in the barn and in the yard, if these are to be supplied from the same source as the house.

Quantity used in stables.

The amount of water used in the barn is even more than that used in the house, a variant depending on the habits of the manager. The minimum quantity needed per day is determined by the number of pailfuls of water which each head actually drinks multiplied by the number of head. But besides this there are many other uses to which water may reasonably be put in connection with stock.

On a dairy farm, there is the water needed to wash cans and bottles and in some cases to furnish a running stream of cold water for the aerator. In some stables a large amount of water is used for washing harnesses and carriages; in others, but a small amount goes for such purposes. Some farmers have concrete floors in cow stables and pig pens and use a hose frequently to wash these floors clean. Other stables never see a stream of water and only see a shovel at infrequent intervals. The amount of water used outside the house is too uncertain a quantity to estimate on the average, but its influence and importance must not be overlooked.

Maximum rate of water-use.

It should now be noted that the quantity of water already referred to is the average quantity used through the twenty-four hours and does not mean the rate at which the water comes from the faucet. For example, three persons in a house use water, according to the above statement, at the rate of seventy-five gallons per day, but a whole day has 1440 minutes, and if seventy-five gallons be divided equally among the number of minutes, it means one gallon in every twenty minutes, or one quart in five minutes. It is obvious that no water-supply system for a house, designed to supply water at the average rate for the twenty-four hours would be satisfactory, since no person would care to wait all day for the amount. To wait five minutes to draw a quart of water would try the patience of any one, and while the total amount of water used in the house will be seventy-five gallons, provision must be made by which it can be drawn in small amounts at much higher rates. Practically all of the amount is used in the daylight hours or in twelve hours out of the twenty-four, so that the rate would be twice the average rate, and with this correction, two quarts of water could be drawn in five minutes.

But even this is too slow, and if one were to take a quart cup to a kitchen faucet and note the time necessary to fill the measure with the water running at a satisfactory rate, he would find that unless the cup was filled in about ten seconds it would be considered too slow a flow. Since it is possible for more than one fixture to be in use at the same time, the pipes ought to be able to deliver the total amount running from different faucets open at the same time, and if it is considered possible for three faucets to run at once, as, for instance, the kitchen faucet, bath-room faucet, and barn faucet, then the supply pipe must be able to deliver, under our assumption, three quarts in ten seconds, or at the rate of about six thousand gallons a day. It is necessary, therefore, to distinguish carefully between the total quantity of water used per day and the rate at which such water is used.

The first of these requirements governs the size of the reservoir from which the water comes or the yield of the well or spring, or the capacity of a pump from a pond to a distributing tank; the other requirement governs the size of the pipe or faucet or the capacity of a pump which supplies direct pressure. It should be noted also that with ordinary fixtures, the rate of delivery and the corresponding sizes of the fixtures are not affected by the number of persons in the house, whereas the first requirement, that is, the total quantity of water used per day, is directly affected by the number of persons.

Variation in maximum rates of water-use.

The quantity of water used, however, is not uniform throughout the day or the week. It is commonly known, for instance, that on Monday, or wash-day, when the well is the only supply, a great deal more water has to be carried on that day than on any other day in the week, and this same increased demand for water is made when the water comes in pipes into the house. Probably about half as much water again is used on Monday as on other days.

Again, in the hot weather of summer, more water is used for bathing and laundry purposes than in cold weather. But, on the other hand, there is a great tendency in cold weather to let the water run in a slow stream from faucets in order to prevent freezing. This has been found to just about double the amount of water used. It is only a reasonable safeguard, therefore, if it has been decided that the family needs are such as to require twenty-five gallons per head per day, to provide for double that amount in order to meet the demands of excessive daily consumption or of the hot and cold weather extremes.

Fire streams.

If a water-supply is to be installed for any house, the possibility of providing mains of sufficient size for adequate fire protection should always be considered, although it may not be found to be a necessary expenditure. In case of a fire a large amount of water is needed for a few hours, entirely negligible if it is computed as an average for the year, but a controlling factor in determining the size of mains or the amount of storage.

A good-sized fire stream delivers about 150 gallons per minute, and for a house in flames, four streams are none too many. The rate of delivery, therefore, for a fire should be at least 600 gallons per minute or a rate of nearly a million gallons per day, and if it is assumed that the fire might burn an hour before being extinguished, 36,000 gallons of water would be used. If a spring or tank is the source of supply, the storage should be 36,000 gallons, and the pipe line from the tank to the hydrants must be large enough to freely deliver water at the rate of 600 gallons per minute. If the distance is not over 500 feet, a four-inch pipe is sufficiently large; but if the distance involved (from the reservoir or tank to the farthest hydrant) is more than about 500 feet, four-inch pipe is not large enough. This is because the friction in a large line of pipe is so great that the water cannot get through in the desired quantity. A four-inch pipe, discharging 600 gallons a minute, would need a fall of one foot in every four feet, while a six-inch pipe would need a fall of only one in thirty. Of course, if the reservoir from which the water comes is at such an elevation that the greater fall is obtainable, the smaller pipe may be used. It is more than likely, though, that the reservoir is about 3000 feet or more away, and the entire fall available only about thirty feet or one foot in one hundred. Then an eight-inch pipe would have to be used.

Whether fire-protection piping, therefore, is a wise investment or not, depends largely on the cost of installation. A four-inch cast-iron pipe laid will cost about forty cents per running foot, while an inch pipe, large enough for everything except fires, will cost about ten cents, so that the excess cost per foot for the sake of fire protection is thirty cents, for a distance up to 500 feet (when the grade is 1 to 4) or $150. If the grade is not 1 to 4, then the pipe must be six-inch, and the excess cost is fifty cents or the cost for 500 feet will be $250. If the distance is greater than 500 and the fall not great, so that an eight-inch pipe has to be used, the excess cost is sixty-five cents a foot, or $650 for a 1000-foot line.

It is sometimes possible to economize by building a large tank containing about 36,000 gallons and using only a small pipe to fill, but always keeping the tank full. Such a tank would contain 4800 cubic feet or would be twenty-two feet square and ten feet deep, or it may be twenty-five feet in diameter and ten feet deep. This tank would have to be erected in the air, higher up than the top of the buildings, and would require heavy supports and a great expenditure. Unless, therefore, a convenient knoll or sidehill is available on which to build a concrete tank, the large pipe direct from the water-supply must be provided for fire protection. Whether it is worth while depends on the cost of insurance and whether it is considered cheaper to pay high rates for insurance or to spend the large sum for protection. A third choice is also open, namely, to carry no insurance and to install no fire hydrants and to run the inevitable risk of losing the house by fire. Perhaps the decision is a mark of the type of man whose property is concerned.

Rain water-supply.

It will often happen that no pond or brook is available for a water-supply, and if water is obtained, it must come directly from the rain. Apparently, this is quite feasible, since an ordinary house has about 1000 square feet area on which rain water might be caught and carried to a tank. In the eastern part of the United States, the annual rainfall is, on the average, 3-3/4 vertical inches per month, or the volume of water from the roof will be 310 cubic feet. This is nearly 80 gallons a day, or enough for three or four people. The rain from the house and barns might be combined, making perhaps 5000 square feet, and giving an ample volume of water for the needs of a dozen people.

In discussing the size of tank necessary to hold rain water for a family supply, it must be remembered that for many weeks at a time no rain occurs, and that a tank must be large enough to tide over these intervals of no rainfall. In the temperate zone there is no regularity in the monthly rates of rainfall. In the eastern part of the United States, the months of June and September are usually the months of least precipitation, although the general impression, perhaps, is that July and August have less rainfall than any other months. The truth is that, while wells and rivers are low in July and August, the actual rainfall for those months is not below the normal, and the low flows in the streams are caused by excessive evaporation and by the demands of growing crops. Although June and September have usually less rainfall than other months, in Boston the fall has been as high as 8.01 inches in June and 11.95 inches in September. Again, in Boston, typifying the eastern part of the United States, and taken because of the great length of rainfall statistics available there, the two months of highest rainfall on the average are March and August, and yet, in each month, in some particular year, the rainfall has been the lowest for any of the twelve months in the year.

As shown by statistics, the average rainfall in each month, taking a period of forty years or so, is practically constant for each month, and it is only the deviations from the average which would make trouble in a supply tank depending upon rainfall. Fortunately, statistics also show that while a month whose average rate of rainfall is three inches may be as low as three tenths of an inch, it is not often that two months of minimum rainfall come together, and in looking over the rainfall statistics the writer finds that for any three consecutive months, including the minimum, the amount of rainfall is generally two thirds of the monthly average for that year; and this is stated in this way because it gives what seems to the writer a basis for determining a fair and reasonable capacity of a rain-water storage tank. It depends, one will notice, on the average annual rainfall; that is, on the depth to which the rainfall would reach in any year if none ran off. This varies from about ten inches in the southeastern part of the United States to one hundred inches in the extreme northwest, the average for the eastern part of the country being about forty-five inches, so that the monthly average is 3.75 inches.

Computation for rain-water storage.

With this for a basis, it may be determined how large a storage tank ought to be, assuming a family of five persons using water at the average rate of 25 gallons per head per day or 125 gallons each day. Doubling this amount to take care of emergencies and of the extra water used in hot weather, let us say that 250 gallons a day must be provided, or 7500 gallons a month. If we could be sure of starting at the beginning of any month with the tank full and that exactly thirty days would be the period of no rainfall, then a tank holding 7500 gallons would be the proper size. Unfortunately, with any month, as August, in which the rainfall may be practically zero, the preceding month may also have been so short of rain that the consumption was equal to or even more than the rainfall, and the month of August would start with no rain in the tank.

But if we take a three-month period, those inequalities will be averaged and the supply will be, so far as one can foresee, ample in amount; that is, we shall take the supply required in three months, namely, 22,500 gallons, and subtract from it the amount of water furnished in the three months, which is presumably two thirds of the average rainfall on the area contributing to the tank. The normal rainfall in three months is three times 3-3/4 inches, or 11-1/4 vertical inches, and if this falls on a roof area of, say, 2000 square feet, the total amount of water is 1850 cubic feet or 13,875 gallons, and two thirds of this is 9250. The tank, then, must hold the difference between the 22,500 gallons and 9250, or 13,250 gallons, whereas a month's supply would be 7500 gallons. The actual tank, therefore, is made to hold a little less than two months' supply. Such a tank would be ten feet deep and fourteen feet square, a good deal larger tank, of course, than one ordinarily finds with a rain water-supply; but the estimate of the use of water has been high and a long period of rainfall has been assumed, so that there is little likelihood of a house with this provision being ever without water.

Computation for storage reservoir on a brook.

In determining the quantity of water that may be taken from a small stream the area of the watershed answers the same purpose as the area of the roof which delivers water into a tank, the only difference being that from the roof all the water is always delivered, except a small proportion that evaporates at the beginning of a rain in summer. From the surface of a watershed, on the contrary, a large amount, and in some cases all of a stream, will be absorbed by the ground and by the vegetation and will never be delivered into the stream which drains an area. On large streams it is fair to assume that, on the average, only one half of the rainfall on the area will reach the stream, while with sandy soils this may be as small as 20 per cent. From December to May inclusive, when the ground is frozen, when there is no vegetation to absorb the water, and when evaporation is very light, practically all of the rainfall reaches the streams. From June to August, on the other hand, when the soil becomes rapidly parched, when vegetation is most active, and when evaporation is high, frequently no rainfall reaches the streams and the ground water sinks lower and lower, so that often streams themselves dry up. It is necessary, therefore, in providing for a definite quantity of water to be taken from a reservoir built on a small stream, to make the reservoir large enough to furnish water from June to September without being supplied with rain. This does not call for a very large dam or a very large storage, and three months' supply will usually be ample.

We have already estimated above that the quantity of water needed for three months will be 45,000 gallons, or about 6000 cubic feet. If the reservoir is built in a small gulley or ravine, its width may be twenty-five feet. If the length of the reservoir or pond formed by the dam is 240 feet, then the reservoir will furnish 6000 cubic feet for every foot of depth, and a reservoir of that size holding one foot of water will tide over a dry season.

Evaporation during these same three months will use up about a foot and a half in depth over whatever area the reservoir covers, so that two and a half feet in depth must be provided above the lowest point to which it is desirable to draw off the water. It would be well to allow a depth of at least ten feet in order to avoid shallow, stagnant pools, and if this depth is provided, even more than the two-and-a-half foot depth mentioned might be withdrawn in extremely dry seasons, though perhaps at some reduction in the quality of the water.

Deficiency from well supplies.

A large number of water-supplies in the country, perhaps the largest number, at present comes from wells, either dug or drilled. It often happens that after plumbing fixtures have been installed with a pump to raise the water to the necessary elevated tank, the increased consumption causes the well to run dry for a number of weeks in the summer. The question then arises, Shall the well supply be supplemented or shall an entirely new supply be developed?

There are two methods of supplementing a dug well supply, and it may be of advantage to point them out. If the sand or gravel in which the water is carried is fine, it may be that the water will not at times of low water enter the well as fast as the pump takes it out. Such a well always has water in it in the morning, but a short pumping exhausts the supply. One remedy here is to provide a more easy path for the water, and that can be done by running out pipe drains in different directions. If there are any evidences that the underground water flows in any direction, then the drains should preferably run out at right angles to this direction, to intercept as much water as possible. The drains must be laid in trenches and be surrounded with gravel, and of course the method is inapplicable if the well is more than about fifteen feet deep, because of the depth of trench involved.



Another remedy is to sink the well deeper, hoping to find a more porous stratum or to increase the head of water in the well. In one well, the writer remembers seeing two lengths of twenty-four-inch sewer pipe, that is, four feet, that had been sunk in the sandy bottom of the well by operating a posthole digger inside and standing on the top of the pipe to furnish the necessary weight for sinking.

Still another remedy is to drive pipe down in the bottom of the well, hoping to find artesian water which will rise into the well from some lower stratum. This method has been successfully employed in the village of Homer, New York, where the public supply formerly came from a dug well twenty feet in diameter. The supply becoming deficient, pipe wells were driven in the bottom and an excellent supply of water found fifty feet below the surface, the water rising up in the dug well to within eight feet of the surface of the ground.

If the well is a driven well and the water in the casing falls so low that the ordinary suction pump will no longer draw, two remedies may be applied. A so-called deep-well pump may be used; that is, a pump which fits inside the piping and can be lowered down to the water level. The ability to bring up water then depends on the power to work the pump and on the presence of the water. Figure 22 shows the principle on which this pump works. At some point, it may be three or four hundred feet below the surface of the ground, a valve A opening upward is set in the well so that it is always submerged. Just above this is a second valve fastened to the lower end of the long pump rod which reaches up to the engine or windmill which operates the pump. At each up stroke water is lifted by the closed valve B and sucked through the open valve A. At each down stroke, the water is held by the closed valve A and forced up through the open valve B.



The other method of developing a greater quantity of water from a deep well is to use air pressure to force the water either the entire distance to the tank or to a point where the suction of an ordinary pump can reach it, as indicated in Fig. 23. In this method an air blower is needed, and since this means an engine for operation, it is not generally feasible, but is suited to occasional needs, where an engine is already installed for other purposes and is therefore available.

The operation is very simple. An air pipe leads from a blower and delivers compressed air at the end of the air pipe, which must be below the level of the water in the well. The pressure of the air then causes the water to rise, the distance depending on the pressure at which the air is delivered.



CHAPTER VI

SOURCES OF WATER-SUPPLY

Having arrived at the quantity of water necessary to supply the needs of the average household, we must next investigate the possible sources from which this quantity can be obtained. Before the advantages of running water in the house are understood, a well is the normal and usual method of securing water, although in a few cases progressive farmers have made use of spring water from the hillsides. It is rare, indeed, for surface water, so called, to be used for purposes of water-supply until after modern plumbing conveniences have been installed. Then the use of surface water becomes almost a necessity because of the large volume of water needed. The only drawback to its use is its questionable quality. Without modern plumbing, a well meets the requirements of family life, but does not answer the demands of convenience. With modern plumbing, a well is found to be pumped dry long before the domestic demands are satisfied. The result is an attempt to secure an unfailing supply, and for this a surface supply is sought.

Let us divide, then, the possible sources of water for domestic consumption into two groups, those found under the surface of the soil and those found on or above the surface. In the first group will come wells and springs, and in the second group will come brooks, streams, and lakes.

Underground waters.

Springs result from a bursting out of underground waters from the confined space in which they have been stored or through which they have been running. Thus in Fig. 24 is seen how water falling on the pervious area a-b is received into the soil and gradually finds its way downward between impervious strata which may be clay or dense rock. At the point B, where the cover layer has, for any reason, been weakened, the pressure of the water forces its way upward and a spring is developed at the point C. Or, conditions may be as shown in Fig. 25, where the confined water, instead of being forced upward by pressure, flows slowly out from the side of a hill, making a spring at the point D, while the water enters the pervious stratum at the point a-b as before.



If the water is held in the ground as in the first case, it is possible to develop the spring artificially; that is, to drill through or bore through the overlying impervious strata so as to allow the escape of the water. When this happens, the water bursts forth exactly as in a natural spring except that under some conditions the pressure may be sufficient to force the water rising in a pipe instead of through the ground to flow above the surface of the ground as a fountain or jet, making what is known as an "artesian well." A true well, on the other hand, may be put down in the ground and through strata where springs could never develop; that is, where no pressure exists in such a way as to bring the water to the surface, as in Fig. 26. The well here is sunk until it reaches the water, and it is safe to say that one can always reach a layer of water in the ground by a well if the well is deep enough.

The flow of underground water is, however, always very uncertain and confusing, and even in localities where water would naturally be expected in quantity, as, for instance, in the bottom of a valley filled with glacial drift, much disappointment is often experienced because the expected water is not found. The city supply of Ithaca, New York, is a case in point. For six miles south of the lake there is a broad, almost level valley filled many hundred feet deep with glacial drift and presumably filled with water flowing at some unknown depth below the surface into the lake. When the city was recovering from the typhoid fever epidemic which, in 1903, committed such ravages, well water seemed to the panic-stricken citizens the only safe water. Geologists were called in, and they gravely asserted that the valley contained glacial drift to a great depth and that an ample supply of pure water could be counted on. It was known that water was met all through this valley at depths of from six to twelve feet and then that there would be found a layer of finely powdered silt to a depth of about one hundred feet, when another layer of water would be found, and that all the private wells reached this layer. When tested by the city, however, it was found that this water-bearing stratum was of too fine material to yield its water freely, and the supply from the depth was altogether inadequate. In one section of the town large quantities of good water were found at a depth of about three hundred feet, and the city thought that other wells of the same depth should add to the quantity, but experiment showed that this three hundred-foot water was limited to one particular section, and after a considerable expenditure of money, an underground water-supply for the city was given up.

Ordinary dug well.

The ordinary well at a farmhouse is what is known as a shallow well or sometimes a "dug well," usually ten to twenty feet deep. This type does not usually pierce any impervious layer and thus reach a water-bearing stratum, otherwise inaccessible. The water is found almost at the surface, and the depth of the well is only that necessary to reach the first water layer. A very good example of this kind of well is to be found on the south shores of Long Island Sound, where a pipe can be driven into the sand at any point, and at a depth of a few feet an abundant and cheap supply of water may be secured. The amount of water that such a well can furnish depends upon the area from which the water comes and upon the size of the particles of sand or gravel through which the water has to percolate, it being evident that the finer the material, the more difficult for the water to penetrate.

The writer remembers superintending the digging of trenches in the streets of a city where the texture of the soil varied continually from clay to sand and even to gravel, all saturated with subsoil water into which wells could have been dug. It was very striking to see how the coarseness of the material affected the quantity of water that had to be pumped from the trenches,—the finest sand requiring only one hand pump at a time, while the coarse gravel required either a dozen men or a steam pump to keep a short trench reasonably free from water. The same conditions exist when a well is in operation, modified by the fact that the coarse material yielding a larger supply will be most quickly exhausted unless the area drained is very large.

A shallow well is most uncertain as to its quantity and is likely to be of doubtful quality. There are, however, some examples of shallow well supplies which furnish large amounts of water; as, for instance, the one at Waltham, Massachusetts, or at Bath, New York,—the latter, a dug well some twenty feet in diameter and about twenty-eight feet deep, furnishing a constant supply of good water to a village of about 4000 people.

Construction of dug wells.

The construction of shallow wells requires little comment. Ordinarily, they are dug down to the water, or to such a depth below the level of the water as is convenient, by the use of an ordinary boat pump to keep down the water, and then are stoned up with a dry wall. Such a well for a single house requires an excavation of about eight feet diameter, with an inside dimension of about five feet.



If the soil at the bottom of the well is sandy, it is possible to take a barrel or a large sewer pipe and sink it into the bottom of the well in the water by taking out material from the inside and loading the outside to keep it pressed down into the sand. This same plan may be used to sink the whole body of the well wall, first supporting the lower course of masonry on a curb, so called (see Fig. 27). This curb is usually made of several thicknesses of two-inch plank well nailed together, the plank breaking joints in the three or four layers used. It is a good plan to have this shoe or curb extend outwardly beyond the walls of the well so that some clearance may be had, otherwise the dirt may press against the walls so hard as to hold it up and prevent its sinking. While this arrangement may be put down in water, it requires some sort of bucket which will dig automatically under water and has not been therefore a customary method except for large excavations where machinery can be installed. There is no reason, however, why the method might not be used for a single house.



In whatever way the well is dug, one point in the construction that needs to be emphasized is that the wall should be well cemented together, beginning about six feet below the surface and reaching up to a point at least one foot above the surface. This is to prevent pollution from the surface gaining direct access to the well, and if this cementing is well done for the distance named, it is not likely that any surface pollution in the vicinity of the well could ever damage the water. Figure 28 shows the section of a well where no such precautions have been taken, and it is evident that not only surface wash, but subsurface pollution may readily contaminate the water. Figure 29 (after Imbeaux), on the other hand, shows a shallow well properly protected by a good wall and water-tight cover. Figure 30 shows a photograph also of this latter type of well. Even if a cesspool or privy is located dangerously near the well, in the second case the fact that the contaminating influence must pass downward through at least six feet of soil before it can enter the well is a guarantee that the danger is reduced to the smallest possible terms.



Deep wells.

Deep wells are of the same general character as shallow wells. Usually, the ground on which the rainfall occurs is more distant, so that the source of the water is often unknown, and usually, also, the stratum from which the water comes is overlaid by an impervious one.



It often happens that there are several layers of water or of water-bearing strata alternating with more or less impervious strata, and that wells might be so dug as to take water from any one of them. Indeed, not infrequently in driving down a pipe to reach water, a fairly satisfactory quantity is obtained at a certain level, and then, in order to increase the supply, the pipe is driven further, shutting off the first supply and reaching some other, less abundant.

Deep wells are reached usually by wrought-iron pipe driven into the ground. Sometimes this is done by taking a one-and-one-quarter inch pipe, with its lower end closed and pointed, and driving it with wooden mauls into the ground. When it has gone six or eight feet, it is pulled up, cleared from the earth, and replaced, to be driven six feet again.



With ordinary soil, the pipe is easily withdrawn with a chain wrench, and two men will drive one hundred feet in a couple of days. When water is reached, a well point is put on through which water may percolate without carrying too much soil. This type of well is suitable for use in soft ground or sand, up to depths of about one hundred feet, and in places where the water is not abundant. It is most useful for testing the ground to see where water may be found and by pumping from such a well to see what quantity of water may be expected. This type is often used as a shallow well, and the author has seen such wells driven only a dozen feet. Such a well has no protection against pollution, and an ordinary dug well is better for shallow depths. A driven well always has a disadvantage also from the ever present danger that the iron pipe will rust through at the top of the ground water and so admit to the well the most polluted part of the drainage.

For larger supplies and for greater depths, a machine like a pile-driver has to be used for forcing down the pipe. This is not usually removed, but driven down as far as possible, and when the limit of the machine has been reached, a smaller size is slipped down inside the driven pipe, to be in turn driven to refusal. In rock, that is, if the well has to penetrate a layer of rock, a drill is used that will work inside of the pipe last driven, and by alternately lifting and dropping the drill, and at the same time twisting it back and forth, a hole through rock may be made many hundred feet below the surface of the ground. Figure 31 shows a cut of a common type of well-drilling machine.

In some soils, not rock, it is necessary to keep the drill going in order to churn up or soften the earth so that the pipe may be lowered. The churned-up soil is removed by a sand pump, which is a hollow tube with a flap valve at the lower end opening inwards and a hook on the upper end. By alternately drilling, pipe-driving, and pumping the wet material, length after length of pipe can be forced into the ground until water of a satisfactory quantity is reached. Very often a jet of water is used to wash out the dirt from the interior of the well instead of a sand pump. As shown by Fig. 32 water under pressure is forced down the small pipe A which runs to the bottom of the well. The large pipe B can then, as the sand is loosened by the water, be driven down by the one thousand-pound hammer M. The water and sand together flow up in the space outside the small pipe and inside the large pipe, overflowing through the waste pipe W. This type of well has been very largely used throughout New York State; on Long Island, in connection with the Brooklyn Water-supply; along the Erie Canal, in connection with the Barge Canal Work, and in New York City, in connection with building foundations.



Sometimes, when a shallow dug well does not furnish the required quantity of water, the amount of water can be increased by driving pipe wells down into water strata below the one from which the dug well takes its supply, so that water will rise to the strata penetrated by the dug well. This has been done to increase the public supplies at Addison and Homer in New York State. Unfortunately, much uncertainty exists in the matter of the yield of driven wells, and an individual undertakes a deep well usually with great reluctance on account of the expense involved and the uncertainty of successful results. In level ground, conditions are not likely to vary in the same valley, so that if one well is proved successful, the probabilities are that wells in the vicinity will be equally so, and yet, at some places, the contrary has proved to be true.

One may estimate the cost of putting down four-inch driven wells as approximately one dollar per foot besides the cost of the pipe, which will be about fifty cents per foot. The cost of one-and-one-half-inch pipe would be considerably less than fifty cents, the cost of driving varying not so much with the size of the pipe as with the soil conditions. The writer recently paid ninety dollars for driving two one-and-one-half-inch wells to a depth of about one hundred feet, the above cost including that of the pipe; the soil conditions, however, were very favorable. In Ithaca the cost of driving one-and-one-quarter-inch pipe is fifteen cents per lineal foot up to about fifty feet deep with the cost of the pipe fifteen cents per foot additional. Below fifty feet deep the cost increases, since the labor and time required for pulling up the pipe is largely increased, and at the same time the rate at which the pipe will drive is notably diminished.

The question of pumping from wells will be considered in a later chapter, together with methods of construction and operation.