An experiment with machine ditching was made in 1903. The worst parts of the marsh were selected, and about 40,000 feet of ditches were cut. These ditches were six inches wide, two feet deep, and the drainage was perfect from the outset. The section of meadow thus drained became so dry in consequence that the grass growing there can now be cut by a machine in summer, whereas formerly the hay could be mown only in winter. The work was so successful that the Newark Common Council appropriated $5,000 to complete the mosquito drainage of the marsh. Of the results obtained up to this spring, Dr. Smith says:

"This Newark marsh problem was an unusual one, and one that would not be likely to recur in the same way at any other point along the coast. Nevertheless, of the entire 3,500 acres of marsh, not 100 acres remain on which there is any breeding whatever, and that is dangerous only in a few places and under certain abnormal conditions. Including old ditches cleaned out, about 360,000 running feet of ditches have been dug on the Newark marshes, partly by machine and partly by hand, and if the work is not entirely successful, that is due to the defects which were not included in the drainage scheme. It is a safe prediction, I think, that Newark will have no early brood of mosquitoes in 1905, comparable with the invasions of 1903 and 1904."

This prophecy has proved true.

The Campaign on Long Island

The wealthy summer residents along the north shore of Long Island, keenly alive to the necessity of driving mosquitoes from the region where they spend so much of their time, have attacked the problem in a scientific, as well as an energetic way. The North Shore Improvement Association intrusted the work to Henry Clay Weeks, a sanitary engineer, with whom was associated, as entomologist, Prof. Charles B. Davenport, Professor of Entomology at the University of Chicago and head of the Cold Spring Biological Laboratory; also F. E. Lutz, an instructor in biology at the University of Chicago. Prof. N. S. Shaler, of Harvard University, the most eminent authority in the country on marine marshes, was retained to make a special examination of the salt marshes with a view to recommending the best means of eliminating what were the most prolific breeding grounds of mosquitoes. A detailed examination of the entire territory was made. Practically every breeding place of mosquitoes, including the smaller pools and streams, and even the various artificial receptacles of water, were located and reported on. Mr. Weeks, with his assistant, then examined each body of water in which mosquito larvae had been found, with a view to devising the best means of preventing the further breeding of mosquitoes in these plague spots. Finally, a report was prepared, together with a map on which was located every natural breeding place.

Investigations in Connecticut

Important investigations have been made in Connecticut by the Agricultural Experiment Station, under the direction of W. E. Britton and Henry L. Viereck, and the results have been most encouraging. Dr. Howard, in his directions for fighting mosquitoes, acknowledges his indebtedness to the very successful experiments carried on at Staten Island. Maryland is aroused to the point of action. Dr. Howard A. Kelley, of Johns Hopkins University, is to cooeperate with Thomas B. Symons, the State entomologist, in carrying the war to the shores of Chesapeake Bay. "Home talent," moreover, can accomplish much. To fight intelligently, let it not be forgotten that the battle should be directed against the larvae. These wrigglers are bred for aquatic life; therefore, it is to all standing water that attention should be directed. Mosquito larvae will not breed in large ponds, or in open, permanent pools, except at the edges, because the water is ruffled by the wind. Any pool can be rendered free from wrigglers by cleaning up the edges and stocking with fish. Every fountain or artificial water basin ought to be so stocked, if it is only with goldfish. The house owner should not overlook any pond, however small, or a puddle of water, a ditch, or any depression which retains water. A half-filled pail, a watering trough, even a tin receptacle will likely be populated with mosquito larvae. Water barrels are favorite haunts for wrigglers.

A Simple Household Remedy

There are those, however, who will obstinately conduct their campaign against the adult mosquito. If energetic, such persons will search the house with a kerosene cup attached to a stick; when this is held under resting mosquitoes the insects fall into the cup and are destroyed. Those possessed of less energy daub their faces and hands with camphor, or with the oil of pennyroyal, and bid defiance to the pests. With others it is, Slap! slap!—with irritation mental as well as physical; for the latter, entomologists recommend household ammonia.

FOOTNOTES:

[3] See Bulletin No. 25, U. S. Department of Agriculture, Division of Entomology.



Part II

PURE FOOD FOR THE HOUSEKEEPER

BY

S. JOSEPHINE BAKER



CHAPTER I

How to Detect Food Adulteration

Adulteration when applied to foodstuffs is a broad, general term, and covers all classes of misrepresentation, substitution, deterioration, or addition of foreign substances; adulteration may be either intentional or accidental, but the housekeeper should be prepared to recognize it and so protect herself and her household.

Food is considered adulterated when it can be classified under any of the following headings:

DEFINITIONS OF ADULTERATION.—(1) If any substance has been mixed or packed with it so as to reduce or lower or injuriously affect its quality or strength.

(2) If any inferior substance has been substituted for it, wholly or in part.

(3) If any valuable constituent has been wholly or in part abstracted from it.

(4) If it consists wholly or in part of diseased or decomposed or putrid or rotten animal or vegetable substance, or any portion of an animal unfit for food, whether manufactured or not, or if it is the product of a diseased animal or one who has died otherwise than by slaughter.

(5) If it be colored or coated or polished or powdered, whereby damage is concealed or it is made to appear better than it really is.

(6) If it contains any added poisonous ingredient or any ingredient which may render such article injurious to health; or if it contains any antiseptic or preservative not evident or not known to the purchaser or consumer.

FOOD LAWS.—There is now in effect in the United States a rigid law against the offering for sale of any article intended for human consumption which is adulterated in any way, without the fact and nature of such adulteration being plainly stated on a label attached to the package containing the article. This law, however, applies only to articles of this nature which originate, or are produced, in one State and offered for sale in another. The purchaser is, therefore, in a great degree protected, but many foodstuffs or manufactured articles may have their origin within the State wherein they are sold, and in this case the only safeguards are those afforded by the laws of the State, city, or town immediately concerned. If these restraining laws do not exist or if they are not enforced the housekeeper must rely upon her own efforts to protect her family from adulterated food.

PERMISSIBLE ADULTERANTS.—In this class are included articles having a food value such as salt, sugar, vinegar, spices, or smoke used as preservatives of meats; or starch when added to the salts composing baking powder, where a certain amount is permissible for the purpose of absorbing moisture.

GENERAL DIRECTIONS.—The ability to select fresh, wholesome meats, poultry, fish, fruits, and vegetables, to determine readily the purity of dairy products, and to detect adulteration or misrepresentation in all classes of foodstuffs must, in most instances, be acquired. Common sense and good reasoning powers are needed here as in every problem of life. While some adulterants can be detected only by trained chemists and by means of tests too difficult and involved for general use, the average housekeeper may amply protect herself from gross imposition by simply cultivating her powers of observation and by making use of a few simple tests well within her grasp and easily applied.

First—Sight, Taste, and Smell.—All are of prime importance in determining the freshness and wholesomeness of foods, especially meats, poultry, fish, vegetables, and fruits. Avoid all highly colored bottled or canned fruits or vegetables; pure preserved fruits, jams, jellies, or relishes may have a good bright color, but never have the brilliant reds and greens so often shown in the artificially colored products.[4] The same is true of canned peas, beans, or Brussels sprouts; here the natural product is a dull, rather dingy green, and all bright green samples must be suspected. Foreign articles of this class are the worst offenders.

All food products should have a clean wholesome odor, characteristic of their particular class. The odor of decomposition can be readily detected; stale and musty odors are soon recognized.

It should be rarely necessary to use the sense of taste, but any food with a taste foreign to the known taste of a similar product of known purity should be discarded or at least suspected.

Second—Price.—Remember that the best and purest food, however high priced, is cheapest in the end. Its value in purity, cleanliness, food value, and strength gives a greater proportionate return than foods priced lower than one might legitimately expect from their supposed character. To cite a few instances: pure Java and Mocha coffee cannot be retailed at twenty cents per pound; therefore, when the housekeeper pays that price she must expect to get chicory mixed with the coffee; if it contains no other adulterant, she may consider herself fortunate. Cheap vanilla is not made from the vanilla bean. These beans sell at wholesale for from ten to fifteen dollars a pound, and the cheap extracts are made from the Tonka bean or from a chemical product known as vanillin. These substances are not harmful, but they are not vanilla. Pure virgin olive oil is made from the flesh of olives after the stones and skin have been removed; cheaper grades are made from the stones themselves and have little food value, while the virgin oil is one of the most nutritious and wholesome of foods.

Such instances might be cited almost without end. Good, pure food demands a good price, and economy defeats its own purpose when it is practiced at the expense of one of the most vital necessities of health and life.

Third—Reliable Dealers.—Select your tradesmen with the same care you bestow in the choice of a physician. A grocer or butcher who has once sold stale, adulterated, or impure wares has forfeited his right to be trusted. A man who is honestly trying to build up a good trade must have the confidence of his customers and it is to his interest to sell only worthy goods; this confidence he can gain only by proving his trustworthiness. When you are convinced of your dealer's honesty give him your trade and do not be lured away by flashy advertisements and the promise of "something for nothing."

PREPARATION FOR CHEMICAL TESTS.—Although the housekeeper will rarely need the use of any chemical tests for the purpose of determining the purity of food, the following directions must be kept in mind if such an expedient is deemed necessary. It will be wise, however, in the majority of cases when the presence of chemical preservatives and adulterants is suspected, to send the article to a chemist for analysis.

1. All refuse matter, such as shells, bones, bran, and skin, must be removed from the edible portion of the food to be tested.

2. If the sample is solid or semi-solid, divide it as finely as possible. All vegetables and meats may be minced in the common household chopping machine. Tea, coffee, whole spices, and the like may be ground or crushed in a mortar or in a spice mill.

3. Milk must be thoroughly stirred or shaken so that the cream is well mixed with the body of the milk.

FLESH FOODS—Meat.—Fresh, wholesome meat is neither pink nor purple; these colors indicate either that the animal was not slaughtered or that it was diseased. Good meat is firm and elastic and when dented with the finger does not retain the impression; it has the same consistency and color throughout; the flesh is marbled, due to the presence of fat distributed among the muscular fibers; it will hardly moisten the finger when touched; it has no disagreeable odor and has a slightly acid reaction so that red litmus paper applied to it should not turn blue.

Wet, sodden, or flabby meat with jellylike fat, a strong putrid odor, and alkaline reaction should be avoided. These signs indicate advanced decomposition, and such meat is unfit for food.

Beef.—This meat should have a fine grain, be firm in texture, with rosy-red flesh and yellowish-white fat.

Lamb and Mutton should have a clear, hard, white fat with the lean part juicy, firm, and of rather light-red color. The flesh should be firm and close of grain.

Veal.—The meat should not be eaten unless the animal was at least six weeks old before slaughtering. The sale of this immature veal, or "bob veal" as it is sometimes called, is prohibited by law in many States. It is unwholesome and may be recognized by its soft, rather mushy consistency and bluish tinge. Good veal has a firm white fat with the lean of a pale-red color.

Pork.—This meat when fresh has a fat that is solid and pure white; if yellow and soft it should be rejected; the lean is pink and the skin like white translucent parchment.

Poultry.—Good poultry is firm to the touch, pink or yellowish in color, is fairly plump, and has a strong skin showing an unbroken surface. It has a fresh odor.

Stale poultry is flabby and shows a bluish color; it becomes green over the crop and abdomen, and the skin is already broken or easily pulled apart in handling. The odor of such a bird is disagreeable and may even be putrid.

Fish.—With the exception of the salted or preserved varieties fish should always be perfectly fresh when eaten. Probably no other article of food is more dangerous to health than fish when it shows even the slightest traces of decomposition. The ability to recognize the earliest signs of staleness is of the utmost importance. Fish deteriorate rapidly and should always be carefully inspected before purchasing.

Fresh fish are firm to the touch, the scales moist and bright, the gills red, and the eyes clear and slightly prominent. When held flat in the hand the fish should remain rigid and the head and tail droop slightly, if at all.

Stale fish are soft and flabby, the skin is dull and the eyes sunken and often covered with a film. The tendency of the head and tail to droop is marked and the fish has a characteristic disagreeable odor. This odor of decomposition is best detected in the gills.

Lobsters and Crabs.—These shellfish should always be alive when purchased. This condition is easily demonstrated by their movements, and the rule should never be disregarded.

Oysters and Clams.—Oysters should not be eaten during the months of May, June, July, and August; these are their breeding months and they are unwholesome during that period. That oysters sometimes contain the germs of typhoid fever is an assured fact; these germs are acquired not from the natural habitat of the oyster in salt water but from the fresh-water, so-called "fattening beds," where the oysters are placed for a season to remove the brackish and salty taste of the sea and to render them more plump. These beds are frequently subject to pollution, and the housekeeper should only purchase oysters from reliable dealers where the purity of the source of the supply is unquestioned.

Clams are in season and may be eaten throughout the year.

All shellfish when fresh have an agreeable fresh odor. The shells should be firmly closed or should close when immersed in water and touched with the finger. If they have been removed from their shells when purchased, the flesh of the fish itself should be firm, clean in appearance and not covered with slime or scum; the odor should be fresh. The odor of dead or decomposed oysters and clams is pungent and disagreeable.

MEAT PRODUCTS—Canned or Potted Meats.—The label on cans containing meat products should state clearly the exact nature of the contents. Deception as to the character of the meat is easy to practice and difficult to detect by any but a trained analyst. The presence of preservatives can also only be detected by chemical analysis. As these products are practically all put on the market by the large packing houses and designed for interstate commerce, they are subject to government inspection, and, therefore, if they bear the government stamp may be considered pure. The point that the housekeeper may consider is the length of time the meat has remained in the can. Put up under proper precautions these canned goods retain their wholesomeness for an almost indefinite period. The heads of the cans should always present a concave surface; if they are convex, it is a sign of decomposition of the contents. When the can is opened the meat should have a clean appearance, free from mold or greenish hue, and the odor should be fresh and not tainted.

Sausages.—If possible, sausages should be homemade, then one may be assured of their purity and freedom from adulteration.

Owing to the rapid color changes and early decomposition of fresh meat, artificial colors are often used to conceal the former, and preservatives like boric acid or saltpeter to retard the latter.

The artificial colors, such as carmine and aniline red, may be detected by observation or by warming the finely divided material on a water bath with a five per cent solution of sodium salicylate. This fluid will extract the color, if present.

Lard.—Good lard is white and granular and has a firm consistency. It has an agreeable characteristic odor and taste. The choicest leaf lard is made from the fat about the kidneys of the hog; the cheaper grades are made from the fat of the whole animal.

FRESH VEGETABLES AND FRUITS—Vegetables.—All green vegetables to be eaten uncooked should be carefully washed and examined for insects, dirt, and foreign matter generally. The ova or eggs of the tapeworm may be ingested with improperly cleaned vegetables. Running water and a clean brush (kept for this purpose) should be used.

Green vegetables should have a fresh, unwilted appearance; any sign of staleness or decay should cause their rejection. Overripe or underripe vegetables are harmful.

Lettuce, celery, and all leaved or stemmed vegetables should be examined to see if the outer leaves have been removed; this may be determined by the distance of the leaves from the stem head. The general signs of disease in vegetables are softening, change of color, and mold.

The following characteristics indicate fresh and wholesome vegetables:

Asparagus.—Firm and white in the stalk with a green, compact tip.

Beans and Peas should have green, not yellow, pods, brittle, and easily snapped open. The vegetable itself should be tender, full and fleshy, not wrinkled or shrunken.

Cabbage, crisp and firm, with a well-rounded and compact head.

Carrots, light red or yellow, with a regular, conical shape, sweet and crisp.

Cauliflower, white, compact head; any tinge of yellow or green generally indicates an inferior quality.

Celery, nearly white in color; large, crisp, and solid stalks, nutty in flavor.

Cucumbers, firm, crisp, with a smooth skin and white flesh.

Lettuce, the head close and compact; the leaves clean, crisp, and sweet. When it is too young or running to seed the taste is bitter. Pale patches on the leaves are caused by mildew and are a sign of decay.

Parsnips, buff in color, with unforked roots, sweet and crisp.

Potatoes, underripe, green potatoes are unfit for food; they contain a poisonous substance which renders them actually harmful. Good potatoes should have a smooth skin and few eyes; the flesh pale and of a uniform color and of a firm consistency. A rough skin, with little depressions, indicates a disease called "scab"; dark-brown patches on the skin are due to a disease called "smut." Potatoes with such diseases are of inferior quality. If green on one side, due to exposure to the sun when growing, the potatoes are unwholesome.

Fruits.—Underripe or green fruit should never be eaten. This condition may be easily detected by the color and consistency of the fruit. Diseased or decayed fruit is known by its change of color, softening, and external mold. Spots on fruit are often caused by a fungus which lowers its quality and renders it less wholesome.

CEREALS AND THEIR PRODUCTS—Cereals.—Particularly when bought in original packages cereals are generally pure and unadulterated. When bought in bulk there may be found dust, dirt, worms, insects, and excessive moisture. These may all be determined by careful inspection. The presence of an undue amount of moisture adds greatly to the weight of cereals and is therefore a fraud. Cereals should be dry to the touch and the individual kernels or particles separate and distinct.

Flour.—By this general term is meant the ordinary wheat flour. It should not be too moist, should have a fine white appearance, remain lumpy, or hold its form, on pressure, not show any particles which cannot be crushed, and when a handful is thrown against the wall, part of it should adhere. The odor and taste should be fresh and clean and not musty or moldy.

The common adulterants are corn and rice meal. If a sample of the flour be thrown on the surface of a glassful of water, the corn and rice, being heavier, will sink; grit and sand may be detected in the same way. If the flour has been adulterated with mineral substances it may be shown by burning a portion down to an ash; the ash of pure flour should not exceed two per cent of the total amount; if mineral substances are present the amount of ash will be greatly increased.

Alum is sometimes added to flour in order to give it a whiter appearance and to produce whiter and lighter bread; it is most unwholesome. It can be detected by the so-called "logwood" test, which is prepared and used as follows:

Make two solutions. The first: a five per cent solution of logwood chips in alcohol. The second: a fifteen per cent solution of ammonium carbonate in water. Make a paste of one teaspoonful of the flour and an equal amount of water; mix with it one-quarter of a teaspoonful of the logwood solution; follow this immediately with one-quarter of a teaspoonful of the ammonium carbonate solution. If alum is present, the paste will show a lavender or blue color; if absent, the mass will become pink, fading to a dirty brown. If the result is doubtful, set the paste aside for several hours, when the colors will show more plainly.

Bread.—Bread should be well baked and not too light or too heavy; the crust should be light brown and adherent to the substance of the bread. The center should be of even consistency, spongy, and firm; it should not pit or be soggy or doughy. The pores or holes should be of practically the same size throughout.

Exceedingly white, light, or porous bread shows the presence of alum. It may be detected by means of the solutions already mentioned in the "logwood" test. Mix one teaspoonful of each solution and add three ounces (six tablespoonfuls) of water; pour this over a lump of bread, free from crust and about an inch square. After the bread has become thoroughly soaked, pour off the excess of liquid and dry the bread in the dish; if alum is present, the mass will show a violet or blue tint, more marked on drying; if absent, a brownish color will appear.

Baking Powders.—Baking powders are of three classes, all having sodium bicarbonate (baking soda) as their alkaline salt. The first style is the commonly used and wholesome mixture of cream of tartar and baking soda; the second has calcium phosphate for the acid salt, and the third contains alum. All have a certain proportion of starch to absorb moisture. Of these the alum powders are the most harmful and should be avoided. Practically all of the well-known brands of baking powder are of the first-mentioned class and wholesome, and are rarely adulterated.

DAIRY PRODUCTS—Milk.—Pure milk should have a specific gravity of from 1.027 to 1.033. Its normal reaction is neutral or slightly acid; it should never be strongly acid. If it is strongly alkaline, i. e., turning red litmus paper blue, it is pretty certain that something in the way of a preservative has been added to it. When left standing for a few hours the cream should show as a slightly yellowish top layer, one-tenth or more of the whole amount; the milk below the cream should be lighter in color and with the slightest bluish tinge. If the color is of a yellowish tinge throughout, the addition of coloring matter must be suspected. "Annatto," a vegetable pigment, is used to give a "rich" tint to milk. To detect it, add one teaspoonful of baking soda to one quart of milk and immerse in it a strip of unglazed paper; in a few hours examine the paper; if annatto is present, it will have become an orange color.[5]

If the whole milk has a blue and thin appearance, or if the cream is scant in quantity, it has probably been diluted with water. The popular idea that chalk is sometimes added to poor milk to make it appear of better quality is erroneous; chalk would always show as a precipitate, as it does not dissolve, and the presence of such a sediment would be a too obvious adulteration to be practiced.

Milk should always be kept at a temperature below 50 deg. F.; above that temperature the bacteria in it multiply with great rapidity and render it unfit for use.

Milk may be preserved for several days if "pasteurized" or "sterilized." Pasteurization consists of heating milk to a temperature of about 167 deg. F., and maintaining it at that degree for twenty minutes. Sterilization means keeping the milk at a temperature of 212 deg. F. for two hours and a half. Immediately after either process the milk should be cooled, then placed in absolutely clean, covered bottles and kept on ice. These methods are not only harmless but actually beneficial in that they destroy any disease germs that might be present.

Chemical preservatives are occasionally found in milk. They may be suspected if the milk is alkaline in reaction and has a disguised taste. The ones most commonly used are boric and salicylic acids and formaldehyde; the two former can only be detected by chemical tests too delicate and intricate to be used by the housewife. Formaldehyde may be tested for by using a solution of one drop of a ten per cent solution of ferric chloride to one ounce of hydrochloric acid.[6] Fill a small porcelain dish one-third full of this solution; add an equal volume of milk and heat slowly over a flame nearly to the boiling point, giving the dish a rotary motion to break up the curd. If formaldehyde is present, the mass will show a violet color, varying in depth with the amount present; if it is absent, the mass turns brown.

Butter.—Good butter has a fresh, sweet odor and an agreeable taste. It should be of the same color and consistency throughout, easily cut and adherent and not crumbly when molded into shapes. Pure butter is very light in color; nearly all that is sold is colored, in order to meet the popular demand for "yellow" butter; annatto and other vegetable and mineral substances are sometimes employed for this purpose. These coloring matters are generally harmless but may be detected by dissolving a portion of the butter in alcohol; the natural color will dissolve, while foreign coloring will not. Butter should consist of eighty-five per cent fat, with the remainder water, casein, and salt. The most common methods of adulteration consist in an excess of water and the addition of oleomargarine. If an excess of water has been added it may be shown by melting the butter; the water and fat will separate in two distinct layers. Oleomargarine has a distinctive meaty smell, like that of cooked meat, and lacks the characteristic odor of pure butter. If pure butter is melted in a spoon, it will not sputter; if oleomargarine is present, it will.

The preservatives sometimes used, namely, boric and salicylic acids and formaldehyde, can only be detected by chemical tests.

Eggs.—Two methods may be used to detect stale eggs. First: make a solution of one part of table salt to ten parts of water and immerse the suspected egg; if it sinks, it is perfectly fresh; if it remains in the water below the surface, it is at least three days old, and if it floats, it is five or more days old.

Second: hold the egg between a bright light and the eye. If it is fresh, it will show a rosy tint throughout, without dark spots, as the air chamber is small; if not fresh, it will look cloudy, with many dark spots present.

TEA AND COFFEE.—These substances are extensively adulterated, but the adulterants are almost without exception harmless.

Tea.—The commonest forms of adulteration of tea are as follows: (a) Exhausted tea leaves which have already been used are dried and added. Their presence may be detected by the weakness of the infusion, made from a given quantity of the suspected tea, compared with a similar infusion made from tea known to be pure. (b) Leaves from other plants are sometimes dried and added; these are easily shown if an infusion is made and when the leaves are thoroughly wet unrolling and comparing them. (c) Green teas may be "faced" or colored with Prussian blue, indigo, French chalk, or sulphate of lime; black teas may be similarly treated with plumbago or "Dutch pink." If teas so treated are shaken up in cold water the coloring matter will wash off. (d) Sand and iron filings are occasionally added for weight; observation, and the fact that they sink when tea is thrown in water, will show their presence. Iron filings may be readily found by using a magnet. (e) The presence of starch may be shown by washing the tea in cold water, straining it, and testing the solution in the following manner: dissolve one-half teaspoonful of potassium iodide in three ounces of water and add as much iodine as the solution will dissolve; a few drops of this solution added to the suspected sample will give a blue color if starch is present.

Coffee.—Coffee should always be purchased in the bean, as ground coffee is much more frequently adulterated and the foreign substances are more difficult to detect.

The adulterants commonly used are: chicory, peas, beans, peanuts, and pellets of roasted wheat flour, rye, corn, or barley.

Fat globules are always present in pure coffee; their presence may be shown by the fact that imitation coffee sinks in water, while pure coffee floats.

Chicory is the most frequently used adulterant; it is added for flavor and to produce a darker infusion, thus giving the impression of greater strength. It is perfectly harmless and as a drink is actually preferred by some people. Its detection is comparatively easy. Chicory grains are dark, gummy, soft, and bitter; coffee grains are hard and brittle; a small amount put in the mouth will demonstrate the difference. Chicory will often adhere to the wheels of a coffee grinder, clogging them on account of its gummy consistency.

When a sample of adulterated coffee is thrown in water the pure coffee floats and leaves the water unstained; chicory sinks almost instantly, coloring the water, while peas and beans sink more slowly but also color the water.

Peas and beans are also detected by the polished appearance of the broken or crushed grains in marked contrast to the dull surface of crushed coffee.

The presence of peas, beans, rye, wheat, bread crumbs, and allied substances may be shown by the fact that they all contain starch.

Make a ten per cent infusion of the suspected coffee; filter it, and decolorize the solution by boiling it with a piece of animal charcoal. Test the decolorized solution by slowly adding a few drops of the "potassium-iodide-iodine solution," directions for preparing which were given under heading of "Tea." A resulting blue color will indicate the presence of starch.

COCOA AND CHOCOLATE.—The adulterants of these substances are generally harmless, as they usually consist of flavoring extracts, sugar, starch, flour, and animal fats. No tests other than flavor, consistency, and smoothness need be considered. Good cocoa and chocolate should be slightly bitter, with a pleasant characteristic odor and taste; they should have a smooth, even consistency and be free from grit or harsh particles.

CANNED AND BOTTLED VEGETABLES AND FRUITS.—In general, acid substances, such as tomatoes and fruits, should not be canned in tin, as the action of the acid tends to dissolve the tin. It is better, therefore, to purchase these articles in glass.

After opening the can the odor and appearance of the contents should be noted. The odor should be clean and fresh, and the slightest trace of any sour, musty, or disagreeable smell should cause the rejection of the food. The appearance should be clean, with no mold; the consistency and color of the fruit or vegetables should be uniform throughout. If the color is brighter than that of a similar article when canned at home, the presence of artificial coloring matter must be suspected. The brilliant green of some brands of peas, beans, or Brussels sprouts is produced by the addition of the salts of copper. This may be proved by leaving the blade of a penknife in the contents of the can for a short time; if copper is present it will be deposited on, and discolor, the blade.

Brightly colored fruits should excite suspicion; this same dictum applies to all brightly colored jams and jellies, as the colors are usually produced by the addition of carmine or aniline red.

The presence of preservatives, salicylic and boric acids, the benzoates, etc., can only be proved by delicate chemical tests.

SUGAR.—Pure granulated or powdered sugar is white and clean. The presence of glucose should be suspected in sugar sold below the market price; it is perfectly harmless, but has a sweetening power of only about two-thirds that of sugar and is added on account of its cheapness and to increase the bulk.

If sand, dirt, or flour are present they may be detected by observation, or by washing the suspected sample in water; flour will not dissolve, sand will sink, and dirt will discolor the water.

SPICES.—Spices should be bought whole and ground in a spice mill as needed; if this is done, there need be little fear of their impurity, for whole spices are difficult to simulate or adulterate. Ground spices may be adulterated with bark, flour, starches, or arrowroot; these adulterants are harmless, but are fraudulent, as they increase the bulk and decrease the strength. Their actual presences can only be demonstrated by a microscopical or chemical examination.

Peppers.—Black pepper is made from the whole berry; white pepper is made from the same berry with the outer husk removed. The adulterants are usually inert and harmless substances, such as flour, mustard, or linseed oil; their presence is obviated by the use of the whole peppercorns, ground as needed.

Red Pepper.—This may be adulterated with red lead; when pure it will be entirely suspended in water; if a sediment falls it is probably red lead.

Mustard.—Practically all of the adulterants of mustard can only be detected by intricate chemical tests. The presence of turmeric may be detected by the appearance of an orange-red color when ammonia is added to a solution of the sample.

Tomato Catsup.—Artificial dyestuffs are common, giving a brilliant crimson or magenta color. Such catsup does not resemble the natural dull red or brown color of the homemade article.

Preservatives, such as boric, salicylic, or benzoic acids and their salts, are sometimes added. While their presence cannot be condoned, yet they are usually present in small amounts and therefore practically harmless.

Pickles.—These should be of a dull-green color. The bright emerald green sometimes observed is due to the presence of the salts of copper; this may be proved by dipping the blade of a penknife in the liquor, as described under the heading of "Canned Goods."

Alum is sometimes used as a preservative and in order to make the pickles crisp. Its presence may be demonstrated by means of the "logwood" test mentioned under the heading of "Flour."

VINEGAR.—Cider vinegar is of a brownish-yellow color and possesses a strong odor of apples.

Wine vinegar is light yellow if made from white wine, and red if made from red wine.

Malt vinegar is brown and has an odor suggestive of sour beer.

Glucose vinegar has the taste and odor of fermented sugar.

Molasses vinegar has the distinctive odor and taste of molasses.

OLIVE OIL.—Pure olive oil has a pleasant, bland taste and a distinctive and agreeable odor, unmistakable in character for that of any other oil. The finest virgin oil is pale green in color, the cheaper grades are light yellow.

The adulterants consist of cotton-seed, corn, mustard, and peanut oils.

When pure olive oil is shaken in a glass or porcelain dish with an equal quantity of concentrated nitric or sulphuric acid[7] it turns from a pale to a dark green color in a few minutes; if under this treatment a reddish to an orange or brown color is produced the presence of a foreign vegetable oil is to be suspected.

FLAVORING EXTRACTS—Vanilla.—This may be wholly or in part the extract of the Tonka bean or may be made from a chemical substance known as vanillin. The best practical working tests as to its purity are the price, taste, and odor. The distinctive odor and taste of vanilla are characteristic and cannot be mistaken.[8]

Lemon.—This extract is often made from tartaric or citric acid. They may be tested for as follows: to a portion of the extract in a test tube add an equal volume of water to precipitate the oil; filter, and add one or two drops of the filtrate to a test tube full of cold, clear limewater; if tartaric acid is present a precipitate will fall to the bottom of the tube. Filter off this precipitate (if present) and heat the contents of the tube; if citric acid is present it will precipitate in the hot limewater.

FOOTNOTE.—Dr. Baker wishes to acknowledge her indebtedness to the following authorities and the volumes mentioned for many helpful suggestions. Pearman and Moore, "Aids to the Analysis of Foods and Drugs"; Albert E. Leach, "Food Inspection and Analysis"; Francis Vacher, "Food Inspector's Hand Book."

FOOTNOTES:

[4] The presence of aniline dyes may be detected by mixing a portion of the suspected sample with enough water to make a thin paste. Wet a piece of white wool cloth or yarn thoroughly with water and place it with the paste in an agate saucepan. Boil for ten minutes, stirring frequently. If a dye has been used the wool will be brightly colored; a brownish or pinkish color indicates the natural coloring matter of the fruit or vegetable.—EDITOR.

[5] A little vinegar added to heated cream or milk produces in the curd a distinct orange color if an aniline dye has been used to make the cream look "rich." The curd will be brown if annatto or caromel has been used. If pure, the curd will be white.—EDITOR.

[6] This acid must be used with great care; no portion of it should ever come in contact with the skin or clothing.

[7] These acids must be used with great care. They should never be allowed to come in contact with the skin or clothing.

[8] Add a little sugar-of-lead solution to the suspected extract; true vanilla extract will give a yellowish-brown precipitate and a pale, straw-colored liquid. If the extract is artificial, the addition of the lead solution will have little or no effect.—EDITOR.



CHAPTER II

Mushroom Poisoning

Symptoms—Treatment—How to Tell Mushrooms—The Common Kind—Other Varieties—The Edible Puffball—Poisonous Mushrooms Frequently Mistaken.

MUSHROOM POISONING.—Vomiting, cramps, diarrhea, pains in legs; possibly confusion, as if drunk, stupidity, followed by excitement, and perhaps convulsions. Lips and face may be blue. Pulse may be weak.

First Aid Rule 1.—Rid the stomach and bowels of remaining poison. Give emetic of mustard, tablespoonful in three glasses of warm water, unless vomiting is already excessive. When vomiting ceases, give tablespoonful of castor oil, or compound cathartic pill. GIVE NO SALTS. Also empty bowels with injection of tablespoonful of glycerin in pint of warm soapsuds and water.

Rule 2.—Antidote the poison. Give a cup of strong coffee and fifteen drops of tincture of belladonna to adult. Repeat both once, after two hours have passed.

Rule 3.—Rest and stimulate. Put patient to bed. Give whisky, a tablespoonful in twice as much water. Give tincture of digitalis, ten drops every two hours, till two or three doses are taken by adult.

Symptoms.—Vomiting and diarrhea come on in a few hours to half a day, with cramps in the stomach and legs. The face and lips may grow blue. There is great prostration. In the case of poisoning by the fly amanita, stupor may appear early, the patient acting as if drunk, and difficult breathing may be a noticeable symptom. Afterwards the patient becomes excited and convulsions develop. The pulse becomes weak and slow. The patient may die in a few hours, or may linger for three or four days. If treatment be thorough, recovery may result.

Treatment.—Unless vomiting has already been excessive, the patient should receive a tablespoonful of mustard mixed with a glassful of tepid water. After the vomiting ceases he should receive a tablespoonful of castor oil, or any cathartic except salts. If the cathartic is vomited, he should receive an injection into the rectum of a tablespoonful of glycerin mixed with a pint of soapsuds and water. Coffee and atropine (or belladonna) are the best antidotes.

If a physician be secured, he will probably give a hypodermic injection of atropine. If a physician is not procurable, the patient should receive a cup of strong coffee, and a dose of ten or fifteen drops of tincture of belladonna in a tablespoonful of water, if an adult. This dose should be repeated once after the lapse of two hours. The patient should be kept in bed, a bedpan being used when the bowels move.

When the pulse begins to grow weak, two tablespoonfuls of whisky and ten drops of the tincture of digitalis should be given to an adult in quarter of a glass of hot water. The digitalis should be repeated every two hours till three or four doses have been taken. The patient must be kept warm with hot-water bottles and blankets.

HOW TO KNOW MUSHROOMS.—One-sixth of one of the poisonous mushrooms has caused death. It is, therefore, impossible to exert too much care in selecting them for food. A novice would much better learn all the characteristics of edible and poisonous mushrooms in the field from an expert before attempting to gather them himself, and should not trust to book descriptions, except in the case of the few edible species described hereafter. It is not safe for a novice to gather the immature or button mushrooms, because it is much more difficult to determine their characteristics than those of the full grown. As reference books, the reader is advised to procure Bulletin No. 15 of the United States Department of Agriculture, entitled "Some Edible and Poisonous Fungi," by Dr. W. G. Farlow, which will be sent without charge on request by the Agricultural Department at Washington; "Studies of American Fungi," by Atkinson, and Miss Marshall's "Mushroom Book," all of which are fully illustrated, and will prove helpful to those interested in edible fungi.

There are no single tests by which one can distinguish edible from poisonous fungi, such as taste, odor, the blackening of a silver spoon, etc., although contrary statements have been made. Even when the proper mushrooms have been eaten, ill effects, death itself, may follow if the mushrooms have been kept too long, have been insufficiently cooked, have been eaten in too large a quantity (especially by children), or if the consumer is the possessor of an unhappy idiosyncrasy toward mushrooms.

No botanic distinction exists between toadstools and mushrooms; mushrooms may be regarded as edible toadstools. They are all, botanically speaking, edible or poisonous fungi. A description follows of the five kinds of fungi most commonly eaten, and the poisonous species which may be mistaken for them.

EDIBLE MUSHROOMS.—1. The Common Mushroom (Agaricus Campestris).—The fungi called agarici are those which have gills, that is, little plates which look like knife blades on the under surface of the top of the mushroom, radiating outward from the stem like the spokes of a wheel. This is the species most frequently grown artificially, and sold in the markets. The top or cap of this mushroom is white, or of varying shades of brown, and measures from one and a half to three or even four inches in diameter. It is found in the latter part of August, in September, and in October, growing in clusters on pastures, fields, and lawns.

The gills are pink or salmon colored in the newly expanded specimen; but as it grows older, or after it is picked, the gills turn dark purple, chestnut brown, or black. This is the important point to remember, since the poisonous species mistaken for it all have white gills. The gills end with abrupt upward curves at the center of the cap without being attached to the stem. In the young mushroom, when the cap is folded down about the stem, the gills are not noticeable, as they are covered by a veil or filmy membrane, a part of which remains attached to the stem (when the top expands), as a ring or collar about the stem a little more than halfway up from the ground. The stem is solid and not hollow, and there is no bulbous enlargement at the base of the stem, surrounded by scales or a collar, as occurs in the fly amanita and other poisonous species. Neither the campestris nor any other mushroom should be eaten when over a day old, since decomposition quickly sets in.



2. Horse Mushroom (Agaricus Arvensis).—This species may be considered with the foregoing, but it differs in being considerably larger (measuring four to ten inches across) and in having a more shiny cap, of a white or brown hue. The ring about the stem is noticeably wider and thicker, and is composed of two distinct layers. The gills are white at first, turning dark brown comparatively late, and the stem is a little hollow as it matures. In some localities it is more common than the campestris in fields and pastures, while in other places it is found only in rich gardens, about hot beds, or in cold frames. It is not distinguished from the campestris by market people, but is often sold with the latter.



3. Shaggy Mane, Ink Cap, or Horsetail Fungus (Coprinus Comatus).—This mushroom possesses the most marked characteristics of any of the edible species; it would seem impossible to mistake its identity from written descriptions and illustrations. It is considered by many superior in flavor to the campestris.

The top or cap does not expand in this mushroom, until it begins to turn black, but remains folded down about the stem like a closed umbrella. Mature specimens are usually three to five, occasionally from eight to ten, inches high. The stem is hollow. The inside of the cap or gills and the stem are snow white. The outer surface of the cap, which is white in young plants, becomes of a faint, yellow-brown or tawny color in mature specimens, and also darker at the top. Delicate scales often rolled up at their lower ends are seen on the exterior of the cap, more readily in mature mushrooms, hence the name "shaggy mane." There is a ring around the stem at the lower margin of the cap, and it is so loosely attached to either the cap or stem that it sometimes drops down to the base of the latter.

The most salient feature of shaggy mane is the change which occurs when it is about a day old; it turns black and dissolves away into an inky fluid, whence the other common name "ink cap." The mushroom should not be eaten when in this condition. The ink cap is usually found growing in autumn, rarely in summer, in richer earth than the common mushroom. One finds it in heaps of street scrapings, by roadsides, in rich lawns, in soils filled with decomposing wood and in low, shaded, moist grounds.



4. Fairy-ring Mushroom (Marasmius Oreades).—This species usually grows on lawns, in clusters which form an imperfect circle or crescent. The ring increases in size each year as new fungi grow on the outside, while old ones toward the center of the circle perish. This mushroom is small and slender, and rarely exceeds two inches in breadth. The cap and the tough and tubular stem are buff, and the gills, few in number and bulging out in the middle, are of a lighter shade of the same color. There is no ring about the stem. Several crops of the fairy-ring mushroom are produced all through the season, but the most prolific growth appears after the late fall rains. There are other fungi forming rings, some of which are poisonous, and they may not be easily distinguished from the edible species; hence great care is essential in gathering them. The under surface of the cap is brown or blackish in the mature plants of poisonous species.



5. Edible Puffball (Lycoperdon Cyathiforme).—Edible puffballs grow in open pastures, and on lawns and grassplots, often forming rings. They are spherical in form, generally from one and a half to two inches, occasionally six inches, in diameter, broad and somewhat flattened at the top, and tapering at the base, white or brown outside. They often present an irregularly checkered appearance, owing to the fact that the white interior shows between the dark raised parts. The interior is at first pure white and of solid consistency, but later becomes softer and yellowish, and then contains an amber-colored juice. After the puffball has matured, the contents change into a brown, dustlike mass, and the top falls off; and it is then inedible. All varieties of puffball with a pure white interior are harmless, if eaten before becoming crumbly and powdery. There is only one species thought to be poisonous, and that has a yellow-brown exterior, while the interior is purple-black, marbled with white.



POISONOUS MUSHROOMS FREQUENTLY MISTAKEN.

To escape eating poisonous mushrooms do not gather the buttons, and be suspicious of those growing in woods and shady spots that show any bright hue, or have a scaly or dotted cap, or white gills.[9] By so doing the following species will be avoided.

Fly Amanita (Amanita Muscaria).—Infusions of this mushroom made by boiling in water are used to kill flies. This species grows in woods and shady places, by roadsides, and along the borders of fields, and is much commoner than the campestris in some localities. It prefers a poor, gravelly soil, and is found in summer.

The stem is hollow and its gills are white. The cap is variously colored, white, orange, yellow, or even brilliant red, and dotted over with corklike particles or warty scales which are easily rubbed off. There is a large, drooping collar about the upper part of the hollow, white stem, and the latter is scaly below with a bulbous enlargement at its base.

The young mushrooms, or buttons, do not exhibit the dotted cap, and the bulbous scaly base may be left in the ground when the mushroom is picked. The fly amanita is usually larger than the common mushroom.



Death Cup or Deadly Agaric (Amanita Phalloides).—This species is more fatal in its effects than the preceding. Its salient feature is a bulbous base surmounted and surrounded by a collar or cup out of which the stem grows. This is often buried beneath the ground, however, so that it may escape notice. The gills and stem are white like the preceding, but the cap is usually not dotted but glossy, white, greenish, or yellow. There is also a broad, noticeable ring about the stem, as in the fly amanita. This mushroom frequents moist, shady spots, also along the borders of fields. It occurs singly, and rarely in fields or pastures.



FOOTNOTES:

[9] The shaggy mane has white gills, but its other features are characteristic.



Part III

THE HOUSE AND GROUNDS

BY

GEORGE M. PRICE



Acknowledgment

We beg to tender grateful acknowledgment to author and publisher for the use of Dr. George M. Price's valuable articles on sanitation. The following extracts are taken from Dr. Price's "Handbook on Sanitation," published by John Wiley & Son, and are covered by copyright.



CHAPTER I

Soil and Sites

Definition.—By the term "soil" we mean the superficial layer of the earth, a result of the geological disintegration of the primitive rock by the action of the elements upon it and of the decay of vegetable and animal life.

Composition.—Soil consists of solids, water, and air.

Solids.—The solid constituents of the soil are inorganic and organic in character.

The inorganic constituents are the various minerals and elements found alone, or in combination, in the earth, such as silica, aluminum, calcium, iron, carbon, sodium, chlorine, potassium, etc.

The characteristics of the soil depend upon its constituents, and upon the predominance of one or the other of its composing elements. The nature of the soil also depends upon its physical properties. When the disintegrated rock consists of quite large particles, the soil is called a gravel soil. A sandy soil is one in which the particles are very small. Sandstone is consolidated sand. Clay is soil consisting principally of aluminum silicate; in chalk, soft calcium carbonate predominates.

The organic constituents of the soil are the result of vegetable and animal growth and decomposition in the soil.

Ground Water.—Ground water is that continuous body or sheet of water formed by the complete filling and saturation of the soil to a certain level by rain water; it is that stratum of subterranean lakes and rivers, filled up with alluvium, which we reach at a higher or lower level when we dig wells.

The level of the ground water depends upon the underlying strata, and also upon the movements of the subterranean water bed. The relative position of the impermeable underlying strata varies in its distance from the surface soil. In marshy land the ground water is at the surface; in other places it can be reached only by deep borings. The source of the ground water is the rainfall, part of which drains into the porous soil until it reaches an impermeable stratum, where it collects.

The movements of the ground water are in two directions—horizontal and vertical. The horizontal or lateral movement is toward the seas and adjacent water courses, and is determined by hydrostatic laws and topographical relations. The vertical motion of the ground water is to and from the surface, and is due to the amount of rainfall, the pressure of tides, and water courses into which the ground water drains. The vertical variations of the ground water determine the distance of its surface level from the soil surface, and are divided into a persistently low-water level, about fifteen feet from the surface; a persistently high-water level, about five feet from the surface, and a fluctuating level, sometimes high, sometimes low.

Ground Air.—Except in the hardest granite rocks and in soil completely filled with water the interstices of the soil are filled with a continuation of atmospheric air, the amount depending on the degree of porosity of the soil. The nature of the ground air differs from that of the atmosphere only as it is influenced by its location. The principal constituents of the air—nitrogen, oxygen, and carbonic acid—are also found in the ground air, but in the latter the relative quantities of O and CO2 are different.

AVERAGE COMPOSITION OF ATMOSPHERIC AIR IN 100 VOLUMES

Nitrogen 79.00 per cent. Oxygen 20.96 " Carbonic acid 0.04 "

AVERAGE COMPOSITION OF GROUND AIR

Nitrogen 79.00 per cent. Oxygen 10.35 " Carbonic acid 9.74 "

Of course, these quantities are not constant, but vary in different soils, and at different depths, times, etc. The greater quantity of CO2 in ground air is due to the process of oxidation and decomposition taking place in the soil. Ground air also contains a large quantity of bacterial and other organic matter found in the soil.

Ground air is in constant motion, its movements depending upon a great many factors, some among these being the winds and movements of the atmospheric air, the temperature of the soil, the surface temperature, the pressure from the ground water from below, and surface and rain water from above, etc.

Ground Moisture.—The interstices of the soil above the ground-water level are filled with air only, when the soil is absolutely dry; but as such a soil is very rare, all soils being more or less damp, soil usually contains a mixture of air and water, or what is called ground moisture.

Ground moisture is derived partly from the evaporation of the ground water and its capillary absorption by the surface soil, and partly by the retention of water from rains upon the surface. The power of the soil to absorb and retain moisture varies according to the physical and chemical, as well as the thermal, properties of the soil.

Loose sand may hold about 2 gallons of water per cubic foot; granite takes up about 4 per cent of moisture; chalk about 15 per cent; clay about 20 per cent; sandy loam 33 to 35 per cent; humus[10] about 40 per cent.

Ground Temperature.—The temperature of the soil is due to the direct rays of the sun, the physicochemical changes in its interior, and to the internal heat of the earth.

The ground temperature varies according to the annual and diurnal changes of the external temperature; also according to the character of the soil, its color, composition, depth, degree of organic oxidation, ground-water level, and degree of dampness. In hot weather the surface soil is cooler, and the subsurface soil still more so, than the surrounding air; in cold weather the opposite is the case. The contact of the cool soil with the warm surface air on summer evenings is what produces the condensation of air moisture which we call dew.

Bacteria.—Quite a large number of bacteria are found in the soil, especially near the surface, where chemical and organic changes are most active. From 200,000 to 1,000,000 bacteria have been found in 1 c.c. of earth. The ground bacteria are divided into two groups—saprophytic and pathogenic. The saprophytic bacteria are the bacteria of decay, putrefaction, and fermentation. It is to their benevolent action that vegetable and animal debris is decomposed, oxidized, and reduced to its elements. To these bacteria the soil owes its self-purifying capacity and the faculty of disintegrating animal and vegetable debris.

The pathogenic bacteria are either those formed during the process of organic decay, and which, introduced into the human system, are capable of producing various diseases, or those which become lodged in the soil through the contamination of the latter by ground water and air, and which find in the soil a favorable lodging ground, until forced out of the soil by the movements of the ground water and air.

Contamination of the Soil.—The natural capacity of the soil to decompose and reduce organic matter is sometimes taxed to its utmost by the introduction into the soil of extraneous matters in quantities which the soil is unable to oxidize in a given period. This is called contamination or pollution of soil, and is due: (1) to surface pollution by refuse, garbage, animal and human excreta; (2) to interment of dead bodies of beasts and men; (3) to the introduction of foreign deleterious gases, etc.[11]

Pollution by Surface Refuse and Sewage.—This occurs where a large number of people congregate, as in cities, towns, etc., and very seriously contaminates the ground by the surcharge of the surface soil with sewage matter, saturating the ground with it, polluting the ground water from which the drinking water is derived, and increasing the putrefactive changes taking place in the soil. Here the pathogenic bacteria abound, and, by multiplying, exert a very marked influence upon the health by the possible spread of infectious diseases. Sewage pollution of the soils and of the source of water supply is a matter of grave importance, and is one of the chief factors of high mortality in cities and towns.

Interment of Bodies.—The second cause of soil contamination is also of great importance. Owing to the intense physicochemical and organic changes taking place within the soil, all dead animal matter interred therein is easily disposed of in a certain time, being reduced to the primary constituents, viz., ammonia, nitrous acid, carbonic acid, sulphureted and carbureted hydrogen, etc. But whenever the number of interred bodies is too great, and the products of decomposition are allowed to accumulate to a very great degree, until the capacity of the soil to absorb and oxidize them is overtaxed, the soil, and the air and water therein, are polluted by the noxious poisons produced by the processes of decomposition.

Introduction of Various Foreign Materials and Gases.—In cities and towns various pipes are laid in the ground for conducting certain substances, as illuminating gas, fuel, coal gas, etc.; the pipes at times are defective, allowing leakage therefrom, and permitting the saturation of the soil with poisonous gases which are frequently drawn up by the various currents of ground air into the open air and adjacent dwellings.

Influence of the Soil on Health.—The intimate relations existing between the soil upon which we live and our health, and the marked influence of the soil on the life and well-being of man, have been recognized from time immemorial.

The influence of the soil upon health is due to: (1) the physical and chemical character of the soil; (2) the ground-water level and degree of dampness; (3) the organic impurities and contamination of the soil.

The physical and chemical nature of the soil, irrespective of its water, moisture, and air, has been regarded by some authorities as having an effect on the health, growth, and constitution of man. The peculiar disease called cretinism, as well as goitre, has been attributed to a predominance of certain chemicals in the soil.

The ground-water level is of great importance to the well-being of man. Professor Pettenkofer claimed that a persistently low water level (about fifteen feet from the surface) is healthy, the mortality being the lowest in such places; a persistently high ground-water level (about five feet from the surface) is unhealthy; and a fluctuating level, varying from high to low, is the most unhealthy, and is dangerous to life and health. Many authorities have sought to demonstrate the intimate relations between a high water level in the soil and various diseases.

A damp soil, viz., a soil wherein the ground moisture is very great and persistent, has been found inimical to the health of the inhabitants, predisposing them to various diseases by the direct effects of the dampness itself, and by the greater proneness of damp ground to become contaminated with various pathogenic bacteria and organisms which may be drawn into the dwellings by the movements of the ground air. As a rule, there is very little to hinder the ground air from penetrating the dwellings of man, air being drawn in through cellars by changes in temperature, and by the artificial heating of houses.

The organic impurities and bacteria found in the soil are especially abundant in large cities, and are a cause of the evil influence of soil upon health. The impurities are allowed to drain into the ground, to pollute the ground water and the source of water supply, and to poison the ground air, loading it with bacteria and products of putrefaction, thus contaminating the air and water so necessary to life.

Diseases Due to Soil.—A great many diseases have been thought to be due to the influence of the soil. An aetiological relation had been sought between soil and the following diseases: malaria, paroxysmal fevers, tuberculosis, neuralgias, cholera, yellow fever, bubonic plague, typhoid, dysentery, goitre and cretinism, tetanus, anthrax, malignant Oedema, septicaemia, etc.

Sites.—From what we have already learned about the soil, it is evident that it is a matter of great importance as to where the site for a human habitation is selected, for upon the proper selection of the site depend the health, well-being, and longevity of the inhabitants. The requisite characteristics of a healthy site for dwellings are: a dry, porous, permeable soil; a low and nonfluctuating ground-water level, and a soil retaining very little dampness, free from organic impurities, and the ground water of which is well drained into distant water courses, while its ground air is uncontaminated by pathogenic bacteria. Exposure to sunlight, and free circulation of air, are also requisite.

According to Parkes, the soils in the order of their fitness for building purposes are as follows: (1) primitive rock; (2) gravel, with pervious soil; (3) sandstone; (4) limestone; (5) sandstone, with impervious subsoil; (6) clays and marls; (7) marshy land, and (8) made soils.

It is very seldom, however, that a soil can be secured having all the requisites of a healthy site. In smaller places, as well as in cities, commercial and other reasons frequently compel the acquisition of and building upon a site not fit for the purpose; it then becomes a sanitary problem how to remedy the defects and make the soil suitable for habitation.

Prevention of the Bad Effects of the Soil on Health.—The methods taught by sanitary science to improve a defective soil and to prepare a healthy site are the following:

(1) Street paving and tree planting. (2) Proper construction of houses. (3) Subsoil drainage.

Street Paving serves a double sanitary purpose. It prevents street refuse and sewage from penetrating the ground and contaminating the surface soil, and it acts as a barrier to the free ascension of deleterious ground air.[12]

Tree Planting serves as a factor in absorbing the ground moisture and in oxidizing organic impurities.

The Proper Construction of the House has for its purpose the prevention of the entrance of ground moisture and air inside the house by building the foundations and cellar in such a manner as to entirely cut off communication between the ground and the dwelling. This is accomplished by putting under the foundation a solid bed of concrete, and under the foundation walls damp-proof courses.

The following are the methods recommended by the New York City Tenement House Department for the water-proofing and damp-proofing of foundation walls and cellars:

Water-proofing and Damp-proofing of Foundation Walls.—"There shall be built in with the foundation walls, at a level of six (6) inches below the finished floor level, a course of damp-proofing consisting of not less than two (2) ply of tarred felt (not less than fifteen (15) pounds weight per one hundred (100) square feet), and one (1) ply of burlap, laid in alternate layers, having the burlap placed between the felt, and all laid in hot, heavy coal-tar pitch, or liquid asphalt, and projecting six (6) inches inside and six (6) inches outside of the walls.

"There shall be constructed on the outside surface of the walls a water-proofing lapping on to the damp-proof course in the foundation walls and extending up to the soil level. This water-proofing shall consist of not less than two (2) ply of tarred felt (of weight specified above), laid in hot, heavy coal-tar pitch, or liquid asphalt, finished with a flow of hot pitch of the same character. This water-proofing to be well stuck to the damp course in the foundation walls. The layers of felt must break joints."

Water-proofing and Damp-proofing of Cellar Floors.—"There shall be laid, above a suitable bed of rough concrete, a course of water-proofing consisting of not less than three (3) ply of tarred felt (not less than fifteen (15) pounds weight per one hundred (100) square feet), laid in hot, heavy coal-tar pitch, or liquid asphalt, finished with a flow of hot pitch of the same character. The felt is to be laid so that each layer laps two-thirds of its width over the layer immediately below, the contact surface being thoroughly coated with the hot pitch over its entire area before placing the upper layer. The water-proofing course must be properly lapped on and secured to the damp course in the foundation walls."

Other methods of damp-proofing foundations and cellars consist in the use of slate or sheet lead instead of tar and tarred paper. An additional means of preventing water and dampness from coming into houses has been proposed in the so-called "dry areas," which are open spaces four to eight feet wide between the house proper and the surrounding ground, the open spaces running as deep as the foundation, if possible. The dry areas are certainly a good preventive against dampness coming from the sides of the house.



Subsoil Drainage.—By subsoil drainage is meant the reducing of the level of the ground water by draining all subsoil water into certain water courses, either artificial or natural. Subsoil drainage is not a modern discovery, as it was used in many ancient lands, and was extensively employed in ancient Rome, the valleys and suburbs of which would have been uninhabitable but for the draining of the marshes by the so-called "cloacae" or drains, which lowered the ground-water level of the low parts of the city and made them fit to build upon. The drains for the conduction of subsoil water are placed at a certain depth, with a fall toward the exit. The materials for the drain are either stone and gravel trenches, or, better, porous earthenware pipes or ordinary drain tile. The drains must not be impermeable or closed, and sewers are not to be used for drainage purposes. Sometimes open, V-shaped pipes are laid under the regular sewers, if these are at the proper depth.

By subsoil drainage it is possible to lower the level of ground water wherever it is near or at the surface, as in swamps, marsh, and other lands, and prepare lands previously uninhabitable for healthy sites.

FOOTNOTES:

[10] Humus is vegetable mold; swamp muck; peat; etc.—EDITOR.

[11] A leak in a gas main, allowing the gas to penetrate the soil, will destroy trees, shrubbery, or any other vegetation with which it comes in contact.—EDITOR.

[12] Town and village paving plans will benefit by knowledge of the recent satisfactory experience of New York City authorities in paving with wood blocks soaked in a preparation of creosote and resin. As compared with the other two general classes of paving, granite blocks, and asphalt, these wood blocks are now considered superior.

The granite blocks are now nearly discarded in New York because of their permeability, expense, and noise, being now used for heavy traffic only.

Asphalt is noiseless and impermeable (thereby serving the "double sanitary purpose" mentioned by Dr. Price).

But the wood possesses these qualities, and has in addition the advantage of inexpensiveness, since it is more durable, not cracking at winter cold and melting under summer heat like the asphalt; and there is but slight cost for repairs, which are easily made by taking out the separate blocks.

These "creo-resinate" wood blocks, recently used on lower Broadway, Park Place, and the congested side streets, are giving admirable results.—EDITOR.



CHAPTER II

Ventilation

Definition.—The air within an uninhabited room does not differ from that without. If the room is occupied by one or more individuals, however, then the air in the room soon deteriorates, until the impurities therein reach a certain degree incompatible with health. This is due to the fact that with each breath a certain quantity of CO2, organic impurities, and aqueous vapor is exhaled; and these products of respiration soon surcharge the air until it is rendered impure and unfit for breathing. In order to render the air pure in such a room, and make life possible, it is necessary to change the air by withdrawing the impure, and substituting pure air from the outside. This is ventilation.

Ventilation, therefore, is the maintenance of the air in a confined space in a condition conducive to health; in other words, "ventilation is the replacing of the impure air in a confined space by pure air from the outside."

Quantity of Air Required.—What do we regard as impure air? What is the index of impurity? How much air is required to render pure an air in a given space, in a given time, for a given number of people? How often can the change be safely made, and how? These are the problems of ventilation.

An increase in the quantity of CO2 [carbon dioxide gas], and a proportionate increase of organic impurities, are the results of respiratory vitiation of the air; and it has been agreed to regard the relative quantity of CO2 as the standard of impurity, its increase serving as an index of the condition of the air. The normal quantity of CO2 in the air is 0.04 per cent, or 4 volumes in 10,000; and it has been determined that whenever the CO2 reaches 0.06 per cent, or 6 parts per 10,000, the maximum of air vitiation is reached—a point beyond which the breathing of the air becomes dangerous to health.

We therefore know that an increase of 2 volumes of CO2 in 10,000 of air constitutes the maximum of admissible impurity; the difference between 0.04 per cent and 0.06 per cent. Now, a healthy average adult at rest exhales in one hour 0.6 cubic foot of CO2. Having determined these two factors—the amount of CO2 exhaled in one hour and the maximum of admissible impurity—we can find by dividing 0.6 by 0.0002 (or 0.02 per cent) the number of cubic feet of air needed for one hour,==3,000.

Therefore, a room with a space of 3,000 cubic feet, occupied by one average adult at rest, will not reach its maximum of impurity (that is, the air in such a room will not be in need of a change) before one hour has elapsed.

The relative quantity of fresh air needed will differ for adults at work and at rest, for children, women, etc.; it will also differ according to the illuminant employed, whether oil, candle, gas, etc.—an ordinary 3-foot gas-burner requiring 1,800 cubic feet of air in one hour.

It is not necessary, however, to have 3,000 cubic feet of space for each individual in a room, for the air in the latter can safely be changed at least three times within one hour, thus reducing the air space needed to about 1,000 cubic feet. This change of air or ventilation of a room can be accomplished by mechanical means oftener than three times in an hour, but a natural change of more than three times in an hour will ordinarily create too strong a current of air, and may cause draughts and chills dangerous to health.

In determining the cubic space needed, the height of the room as well as the floor space must be taken into consideration. As a rule the height of a room ought to be in proportion to the floor space, and in ordinary rooms should not exceed fourteen feet, as a height beyond that is of very little advantage.[13]

Forces of Ventilation.—We now come to the question of the various modes by which change in the air of a room is possible. Ventilation is natural or artificial according to whether artificial or mechanical devices are or are not used. Natural ventilation is only possible because our buildings and houses, their material and construction, are such that numerous apertures and crevices are left for air to come in; for it is evident that if a room were hermetically air-tight, no natural ventilation would be possible.

The properties of air which render both natural and artificial ventilation possible are diffusion, motion, and gravity. These three forces are the natural agents of ventilation.

There is a constant diffusion of gases taking place in the air; this diffusion takes place even through stone and through brick walls. The more porous the material of which the building is constructed, the more readily does diffusion take place. Dampness, plastering, painting, and papering of walls diminish diffusion, however.

The second force in ventilation is the motion of air or winds. This is the most powerful agent of ventilation, for even a slight, imperceptible wind, traveling about two miles an hour, is capable, when the windows and doors of a room are open, of changing the air of a room 528 times in one hour. Air passes also through brick and stone walls. The objections to winds as a sole mode of ventilation are their inconstancy and irregularity. When the wind is very slight its ventilating influence is very small; on the other hand, when the wind is strong it cannot be utilized as a means of ventilation on account of the air currents being too strong and capable of exerting deleterious effects on health.

The third, the most constant and reliable, and, in fact, principal agent of ventilation is the specific gravity of the air, and the variations in the gravity and consequent pressure which are results of the variations in temperature, humidity, etc. Whenever air is warmer in one place than in another, the warmer air being lighter and the colder air outside being heavier, the latter exerts pressure upon the air in the room, causing the lighter air in the room to escape and be displaced by the heavier air from the outside, thus changing the air in the room. This mode of ventilation is always constant and at work, as the very presence of living beings in the room warms the air therein, thus causing a difference from the outside air and effecting change of air from the outside to the inside of the room.

Methods of Ventilation.—The application of these principles of ventilation is said to be accomplished in a natural or an artificial way, according as mechanical means to utilize the forces and properties of air are used or not. But in reality natural ventilation can hardly be said to exist, since dwellings are so constructed as to guard against exposure and changes of temperature, and are usually equipped with numerous appliances for promoting change of air. Windows, doors, fireplaces, chimneys, shafts, courts, etc., are all artificial methods of securing ventilation, although we usually regard them as means of natural ventilation.

Natural Ventilation.—The means employed for applying the properties of diffusion are the materials of construction. A porous material being favorable for diffusion, some such material is placed in several places within the wall, thus favoring change of air. Imperfect carpenter work is also a help, as the cracks and openings left are favorable for the escape and entrance of air.

Wind, or the motion of air, is utilized either directly, through windows, doors, and other openings; or indirectly, by producing a partial vacuum in passing over chimneys and shafts, causing suction of the air in them, and the consequent withdrawal of the air from the rooms.

The opening of windows and doors is possible only in warm weather; and as ventilation becomes a problem only in temperate and cold weather, the opening of windows and doors cannot very well be utilized without causing colds, etc. Various methods have therefore been proposed for using windows for the purposes of ventilation without producing forcible currents of air.

The part of the window best fitted for the introduction of air is the space between the two sashes, where they meet. The ingress of air is made possible whenever the lower sash is raised or the upper one is lowered. In order to prevent cold air from without entering through the openings thus made, it has been proposed by Hinkes Bird to fit a block of wood in the lower opening; or else, as in Dr. Keen's arrangement, a piece of paper or cloth is used to cover the space left by the lifting or lowering of either or both sashes. Louvers or inclined panes or parts of these may also be used. Parts or entire window panes are sometimes wholly removed and replaced by tubes or perforated pieces of zinc, so that air may come in through the apertures. Again, apertures for inlets and outlets may be made directly in the walls of the rooms. These openings are filled in with porous bricks or with specially made bricks (like Ellison's conical bricks), or boxes provided with several openings. A very useful apparatus of this kind is the so-called Sheringham valve, which consists of an iron box fitted into the wall, the front of the box facing the room having an iron valve hinged along its lower edge, and so constructed that it can be opened or be closed at will to let a current of air pass upward. Another very good apparatus of this kind is the Tobin ventilator, consisting of horizontal tubes let through the walls, the outer ends open to the air, but the inner ends projecting into the room, where they are joined by vertical tubes carried up five feet or more from the floor, thus allowing the outside air to enter upwardly into the room. This plan is also adapted for filtering and cleaning the incoming air by placing cloth or other material across the lumen of the horizontal tubes to intercept dust, etc. McKinnell's ventilator is also a useful method of ventilation, especially of underground rooms.



To assist the action of winds over the tops of shafts and chimneys, various cowls have been devised. These cowls are arranged so as to help aspirate the air from the tubes and chimneys, and prevent a down draught.

The same inlets and outlets which are made to utilize winds may also be used for the ventilation effected by the motion of air due to difference in the specific gravity of outside and inside air. Any artificial warming of the air in the room, whether by illuminants or by the various methods of heating rooms, will aid in ventilating it, the chimneys acting as powerful means of removal for the warmer air. Various methods have also been proposed for utilizing the chimney, even when no stoves, etc., are connected with it, by placing a gaslight within the chimney to cause an up draught and consequent aspiration of the air of the room through it.



The question of the number, relative size, and position of the inlets and outlets is a very important one, but we can here give only an epitome of the requirements. The inlet and outlet openings should be about twenty-four inches square per head. Inlet openings should be short, easily cleaned, sufficient in number to insure a proper distribution of air; should be protected from heat, provided with valves so as to regulate the inflow of air, and, if possible, should be placed so as to allow the air passing through them to be warmed before entering the room.[14] Outlet openings should be placed near the ceiling, should be straight and smooth, and, if possible, should be heated so as to make the air therein warmer, thus preventing a down draught, as is frequently the case when the outlets become inlets.



Artificial Ventilation.—Artificial ventilation is accomplished either by aspirating the air from the building, known as the vacuum or extraction method, or by forcing into the building air from without; this is known as the plenum or propulsion method.

The extraction of the air in a building is done by means of heat, by warming the air in chimneys or special tubes, or by mechanical means with screws or fans run by steam or electricity; these screws or fans revolve and aspirate the air of the rooms, and thus cause pure air to enter.



The propelling method of ventilation is carried out by mechanical means only, air being forced in from the outside by fans, screws, bellows, etc.

Artificial ventilation is applicable only where a large volume of air is needed, and for large spaces, such as theaters, churches, lecture rooms, etc. For the ordinary building the expense for mechanical contrivances is too high.

On the whole, ventilation without complex and cumbersome mechanisms is to be preferred.[15]

FOOTNOTES:

[13] In cerebro-spinal meningitis, tuberculosis, and pneumonia, fresh air is curative. Any person, sick or well, cannot have too much fresh air. The windows of sleeping rooms should always be kept open at night.—EDITOR.

[14] These outlets may be placed close to a chimney or heating pipes. Warm air rises and thus will be forced out, allowing cool fresh air to enter at the inlets.—EDITOR.

[15] The ordinary dwelling house needs no artificial methods of ventilation. The opening and closing of windows will supply all necessary regulation in this regard. The temperature of living rooms should be kept, in general, at 70 deg. F. Almost all rooms for the sick are unfortunately overheated. Cool, fresh air is one of the most potent means of curing disease. Overheated rooms are a menace to health.—EDITOR.



CHAPTER III

Warming

Ventilation and Heating.—The subject of the heating of our rooms and houses is very closely allied to that of ventilation, not only because both are a special necessity at the same time of the year, but also because we cannot heat a room without at the same time having to ventilate it by providing an egress for the products of combustion and introducing fresh air to replace the vitiated.

Need of Heating.—In a large part of the country, and during the greater period of the year, some mode of artificial heating of rooms is absolutely necessary for our comfort and health. The temperature of the body is 98 deg. to 99 deg. F., and there is a constant radiation of heat due to the cooling of the body surface. If the external temperature is very much below that of the body, and if the low temperature is prolonged, the radiation of heat from the body is too rapid, and colds, pneumonia, etc., result. The temperature essential for the individual varies according to age, constitution, health, environment, occupation, etc. A child, a sick person, or one at rest requires a relatively higher temperature than a healthy adult at work. The mean temperature of a room most conducive to the health of the average person is from 65 deg. to 75 deg. F.

The Three Methods of Heating.—The heating of a room can be accomplished either directly by the rays of the sun or processes of combustion. We thus receive radiant heat, exemplified by that of open fires and grates.

Or, the heating of places can be accomplished by the heat of combustion being conducted through certain materials, like brick walls, tile, stone, and also iron; this is conductive heat, as afforded by stoves, etc.

Or, the heat is conveyed by means of air, water, or steam from one place to another, as in the hot-water, hot-air, and steam systems of heating; this we call convected heat.

There is no strict line of demarcation differentiating the three methods of heating, as it is possible that a radiant heat may at the same time be conductive as well as convective—as is the case in the Galton fireplace, etc.

Materials of Combustion.—The materials of combustion are air, wood, coal, oil, and gas. Air is indispensable, for, without oxygen, there can be no combustion. Wood is used in many places, but is too bulky and expensive. Oil is rarely used as a material of combustion, its principal use being for illumination. Coal is the best and cheapest material for combustion. The chief objection against its use is the production of smoke, soot, and of various gases, as CO, CO2, etc. Gas is a very good, in fact, the best material for heating, especially if, when used, it is connected with chimneys; otherwise, it is objectionable, as it burns up too much air, vitiates the atmosphere, and the products of combustion are deleterious; it is also quite expensive. The ideal means of heating is electricity.

Chimneys.—All materials used for combustion yield products more or less injurious to health. Every system of artificially heating houses must therefore have not only means of introducing fresh air to aid in the burning up of the materials, but also an outlet for the vitiated, warmed air, partly charged with the products of combustion. These outlets are provided by chimneys. Chimneys are hollow tubes or shafts built of brick and lined with earthen pipes or other material inside. These tubes begin at the lowest fireplace or connection, and are carried up several feet above the roof. The thickness of a chimney is from four to nine inches; the shape square, rectangular, or, preferably, circular. The diameter of the chimney depends upon the size of the house, the number of fire connections, etc. It should be neither too small nor too large. Square chimneys should be twelve to sixteen inches square; circular ones from six to eight inches in diameter for each fire connection. The chimney consists of a shaft, or vertical tube, and cowls placed over chimneys on the roof to prevent down draughts and the falling in of foreign bodies. That part of the chimney opening into the fireplace is called the throat.

Smoky Chimneys.—A very frequent cause of complaint in a great many houses is the so-called "smoky chimney"; this is the case when smoke and coal gas escape from the chimney and enter the living rooms. The principal causes of this nuisance are:

(1) A too wide or too narrow diameter of the shafts. A shaft which is too narrow does not let all the smoke escape; one which is too wide lets the smoke go up only in a part of its diameter, and when the smoke meets a countercurrent of cold air it is liable to be forced back into the rooms.

(2) The throat of the chimney may be too wide, and will hold cold air, preventing the warming of the air in the chimneys and the consequent up draught.

(3) The cowls may be too low or too tight, preventing the escape of the smoke.

(4) The brickwork of the chimney may be loose, badly constructed, or broken into by nails, etc., thus allowing smoke to escape therefrom.

(5) The supply of air may be deficient, as when all doors and windows are tightly closed.

(6) The chimney may be obstructed by soot or some foreign material.

(7) The wind above the house may be so strong that its pressure will cause the smoke from the chimney to be forced back.

(8) If two chimneys rise together from the same house, and one is shorter than the other, the draught of the longer chimney may cause an inversion of the current of air in the lower chimney.

(9) Wet fuel when used will cause smoke by its incomplete combustion.

(10) A chimney without a fire may suck down the smoke from a neighboring chimney; or, if two fireplaces in different rooms are connected with the same chimney, the smoke from one room may be drawn into the other.

Methods of Heating. Open Fireplaces and Grates.—Open fireplaces and fires in grates connected with chimneys, and using coal, wood, or gas, are very comfortable; nevertheless there are weighty objections to them. Firstly, but a very small part of the heat of the material burning is utilized, only about twelve per cent being radiated into the room, the rest going up the chimney. Secondly, the heat of grates and fireplaces is only local, being near the fires and warming only that part of the person exposed to it, leaving the other parts of the room and person cold. Thirdly, the burning of open fires necessitates a great supply of air, and causes powerful draughts.