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Sept. 7th and 8th, in 24 hours, 6.88 inches of rain fell, the greatest quantity recorded in one day.
In 1846—still earlier by four years—the rain-fall in Waltham was 26.90 inches—the least recorded by the same observations. It fell, as shown in the table: Number of rainy days, 49; total rain-fall, 26.90.
3 days gave between .05 and .10 inches. 7 " .10 " .20 " 10 " .20 " .30 " 6 " .30 " .40 " 4 " .40 " .50 " 3 " .50 " .60 " 2 " .70 " .80 " 3 " .80 " .90 " 1 " .90 " 1.00 " 3 " 1.00 " 1.10 " 2 " 1.10 " 1.20 " 1 " 1.20 " 1.30 " 2 " 1.40 " 1.50 " 1 " 1.50 " 1.60 " 1 " 2.40 " 2.50 "
The rain-fall in 1852 was very near the average for thirty years; and the quantity falling in single storms, on sixty-three different occasions, as registered by Dr. Hobbs, was as follows: Number of storms, 63; total rain-fall, 42.24.
7 storms gave less than .10 inches. 11 " between .10 and .20 " 9 " " .20 " .30 " 5 " " .30 " .40 " 6 " " .40 " .50 " 5 " " .50 " .60 " 1 " " .60 " .70 " 1 " " .70 " .80 " 3 " " .80 " .90 " 1 " " .90 " 1.00 " 5 " " 1.00 " 1.10 " 1 " " 1.10 " 1.20 " 1 " " 1.20 " 1.30 " 1 " " 1.40 " 1.50 " 3 " " 1.60 " 1.70 " 1 " in 5 days 3.16 " 1 " " 4 " 4.38 " 1 " " 6 " 5.35 "
These tables are sufficient to show that provision must be made to carry off much greater quantities of water from lands in this country than in England. We add a table of the greatest fall of rain in any one day, for each month, and for the year, from April, 1824, to 1st January, 1859. It also was abstracted from the manuscript of observations by Dr. Hobbs, and will be, we think, quite useful:
========================================================================== YEARS March June September December Greatest February May August November Fall in the January April July October Year -+ + + + + + + + + + + + + 1824 0.76 0.67 0.53 0.44 1.90 2.54 0.81 0.76 1.80 2.54 1825 2.16 2.61 0.27 1.23 1.37 0.91 2.51 0.89 1.32 0.71 2.40 2.61 1826 1.80 0.56 1.67 0.89 0.39 1.78 0.87 1.80 1.57 1.37 1.22 1.41 1.87 1827 3.81 1.55 2.42 0.66 1.36 3.16 4.93 2.22 3.85 1.39 4.93 1828 0.60 1.48 1.82 2.06 2.01 1.44 1.52 0.14 1.82 1.52 1.90 0.29 2.06 1829 3.86 1.98 4.12 2.35 1.15 0.97 1.92 0.97 1.39 1.00 1.25 1.58 4.12 1830 1.31 1.17 2.68 2.28 0.78 1.84 2.45 2.40 1.20 2.64 2.44 2.68 1831 0.64 1.48 2.32 2.12 1.79 1.87 2.27 1.00 1.00 2.82 1.24 0.15 2.82 1832 2.68 1.59 2.00 4.48 2.52 1.24 2.13 0.80 1.50 2.60 1.34 4.48 1833 0.83 2.57 0.98 2.03 1.42 0.64 2.75 2.32 3.12 1.27 3.12 1834 0.64 1.31 0.94 2.35 1.87 2.12 0.73 1.25 1.89 2.42 0.92 2.42 1835 1.44 0.88 2.48 2.48 1.18 1.52 4.72 1.32 1.57 3.28 0.74 2.32 4.72 1836 2.72 3.04 2.26 1.86 1.29 2.24 1.04 0.72 0.36 2.04 1.50 1.68 3.04 1837 3.62 1.50 1.14 1.68 1.46 1.30 0.72 0.78 0.66 1.46 0.81 1.68 3.62 1838 1.64 0.75 0.76 1.32 1.40 1.67 0.82 1.40 3.84 1.10 2.46 1.00 3.84 1839 0.70 0.80 0.58 4.06 2.98 0.94 1.08 3.54 0.70 1.60 0.80 1.92 4.06 1840 1.68 2.20 1.54 2.12 1.16 1.08 1.40 2.72 1.28 1.04 3.72 1.12 3.72 1841 1.44 1.12 1.32 1.64 0.90 0.75 0.64 2.82 2.78 2.66 1.05 1.70 2.82 1842 0.54 1.22 1.16 0.64 0.47 2.10 0.68 1.44 0.96 0.34 1.10 2.02 2.10 1843 1.60 1.64 2.50 1.34 0.34 1.04 1.98 2.58 0.52 1.94 1.28 2.58 1844 4.14 2.06 0.24 0.58 0.78 0.86 1.34 1.76 2.30 1.86 1.28 4.14 1845 2.42 1.70 1.14 0.70 1.02 1.03 1.20 1.66 0.88 1.16 3.32 1.46 3.32 1846 1.54 2.46 1.16 1.18 0.82 1.46 0.49 0.56 0.55 0.54 1.02 2.46 1847 1.18 2.74 1.66 1.12 0.84 1.28 0.56 1.86 2.16 0.64 2.74 3.02 3.02 1848 1.44 1.56 2.68 0.68 2.28 1.00 0.72 1.24 1.48 2.96 0.88 1.00 2.96 1849 1.36 0.40 2.30 0.92 1.28 0.72 1.52 2.08 1.12 2.60 2.48 1.76 2.60 1850 2.56 1.92 1.84 2.68 2.80 1.20 1.20 3.68 6.88 1.04 2.16 1.92 6.88 1851 0.80 1.84 0.56 3.60 1.92 1.12 0.96 0.32 1.15 1.47 2.25 0.89 3.60 1852 1.06 0.88 1.15 4.38 1.47 1.69 0.66 4.16 1.19 1.61 1.59 0.89 4.38 1853 0.92 1.33 1.03 1.12 2.39 0.42 1.03 2.36 2.14 1.95 1.67 1.35 2.39 1854 0.83 1.60 1.25 1.88 2.57 1.50 1.58 0.48 2.33 1.82 3.25 1.43 3.25 1855 3.37 3.08 0.80 1.33 0.39 1.23 1.93 0.75 0.70 1.77 2.22 1.24 3.37 1856 1.30 0.63 1.97 2.93 0.66 1.30 4.23 2.42 0.87 0.88 1.20 4.23 1857 1.50 0.54 1.55 3.68 1.28 0.96 2.43 2.00 0.87 3.54 0.67 1.28 3.68 1858 1.12 1.18 0.35 1.28 1.00 3.86 1.35 2.21 1.64 1.22 1.36 1.40 3.86 ==========================================================================
The following table shows the record of rain-fall, as kept for one year; it was selected as a representative year, the total quantity falling being equal to the average. For the year 1840: Number of rainy days, 50; total rain-fall, 42.00.
====================================================================== DAYS March June September December February May August November January 1840 April July October - - 1 0.55 0.14 2.72 0.64 2 0.08 0.05 3 0.32 4 1.08 0.10 5 1.16 0.63 6 0.50 7 8 0.20 9 0.25 3.72 10 2.20 1.28 11 0.10 12 2.12 0.54 13 0.14 1.12 14 0.58 0.70 15 0.36 16 17 18 19 0.82 0.24 0.68 1.04 20 1.54 0.44 21 0.98 1.04 22 0.52 2.20 23 1.68 0.96 0.18 24 1.40 25 0.16 0.35 26 0.18 27 0.17 0.30 28 29 1.80 0.10 1.40 30 1.42 0.08 1.04 31 - - Total 1.68 2.78 3.28 5.17 2.28 2.41 2.09 5.22 2.89 3.65 7.35 3.20 ======================================================================
The average quantity of rain which has fallen in Waltham, during the important months of vegetation, from 1824 to 1858 inclusive—a period of thirty-five years—is for—
April. May. June. July. Aug. Sept. 3.96 3.71 3.18 3.38 4.50 3.52
Average for the six months, 22.25.
It will be noticed, that the average for the month of August is about 33 per cent. larger than for June and July. The quantity of rain falling in each month, as registered at the Cambridge Observatory, is as follows:
MEAN OF OBSERVATIONS FOR TWELVE YEARS.
Jan. Feb. Mar. Apr. May. June. 2.39 3.19 3.47 3.64 3.74 3.13
July. Aug. Sept. Oct. Nov. Dec. 2.57 5.47 4.27 3.73 4.57 4.31
Spring. Summer. Autumn. Winter. 10.85 11.17 12.57 9.89
Average quantity per year, 44.48.
The quantity falling from January to July, is much less than falls from July to January.
The great quantity of snow which falls in New England during the Winter months, and is carried off mainly in the Spring, usually floods the low lands, and should be taken into account in establishing the size of pipe to be used in a system of drainage. The following observations of the average depth of snow, have been made at the places cited, and are copied, by Blodget, from various published notices:
Oxford Co., Me. 12 years 90 inches per year. Dover, N. H. 10 " 68.6 " " Montreal 10 " 67 " " Burlington, Vt. 10 " 85 " " Worcester, Mass. 12 " 55 " " Amherst, " 7 " 54 " " Hartford, Conn. 24 " 43 " " Lambertville, N. J. 8 " 25.5 " " Cincinnati 16 " 19 " " Burlington, Iowa 4 " 15.5 " " Beloit, Wisconsin 3 " 25 " "
One-tenth the depth of snow is taken as its equivalent in water, for general purposes, though it gives too small a quantity of water in southern latitudes, and in extreme latitudes too great a quantity. The rule of reduction of snow to water, in cold climates, is one inch of water to twelve of snow.
The proportion of the annual downfall of rain which is collectable into reservoirs—or, in other words, the per-centage of the rain-fall which drains off—is well shown in a table used by Ellwood Morris, Esq., C. E., in an article on "The Proposed Improvement of the Ohio River" (Jour. Frank. Inst., Jan., 1858), in which we find, that, in eighteen series of observations in Great Britain, the ratio, or per cent. of the rain-fall which drains off is 65-1/2, or nearly two-thirds the rain-fall.
Seven series of observations in America are cited as follows:
========================================================================== Name Annual Drainage Ratio, or of rain-fall, flowing per ct. of No. Drainage Area. in inches. away, in the rain Authorities. inches. which drains off. - - - 1 Schuylkill Navigation Reservoirs 36 18 50 Morris and Smith. 2 Eaton Brook 34 23 66 } 3 Madison Brook 35 18 50 }McAlpine. 4 Patroon's Brook 46 25 55 } 5 " " 42 18 42 } 6 Long Pond 40 18 44 Boston Water Com'rs. 7 West Fork Reservoir 36 14 40 W. Milnor Roberts. - - - Totals 269 134 347 Averages 38 19 50 ==========================================================================
These examples show an average rain-fall of thirty-eight vertical inches, and an annual amount, collectable in reservoirs, of nineteen inches, or fifty per cent.
The per-centage of water of drainage from land under-drained with tile, would be greater than that which is collectable in reservoirs from ordinary gathering-grounds.
If a soil were perfectly saturated with water, that is, held as much water in suspension as possible to hold without draining off, and drains were laid at a proper depth from the surface, and in sufficient number to take off all surplus water, then the entire rain-fall upon the surface would be water of drainage—presuming, of course, the land to be level, and the air at saturation, so as to prevent evaporation. The water coming upon the surface, would force out an equal quantity of water at the bottom, through the drains—the time occupied by the process, varying according to the porous or retentive nature of the soil; but in ordinary circumstances, it would be, perhaps, about forty-eight hours. Drains usually run much longer than this after a heavy rain, and, in fact, many run constantly through the year, but they are supplied from lands at a higher level, either near by or at a distance.
If, on the other hand, the soil were perfectly dry, holding no water in suspension, then there would be no water of drainage until the soil had become saturated.
Evaporation is constantly carrying off great quantities of water during the warm months, so that under-drained soil is seldom in the condition of saturation, and, on account of the supply by capillary attraction and by dew, is never thoroughly dry; but the same soil will, at different times, be at various points between saturation and dryness, and the water of drainage will be consequently a greater or less per centage of the rain-fall.
An experiment made by the writer, to ascertain what quantity of water a dry soil would hold in suspension, resulted as follows: A soil was selected of about average porosity, so that the result might be, as nearly as possible, a mean for the various kinds of soil, and dried by several days' baking. The quantity of soil then being carefully measured, a measured quantity of water was supplied slowly, until it began to escape at the bottom. The quantity draining away was measured and deducted from the total quantity supplied. It was thus ascertained that one cubic foot of earth held 0.4826+ cubic feet of water, which is a little more than three and one-half gallons. A dry soil, four feet deep, would hold a body of water equal to a rain-fall of 23.17 inches, vertical depth, which is more than would fall in six months.
The quantity which is not drained away is used for vegetation or evaporated; and the fact, that the water of drainage is so much greater in proportion to the rain-fall in England than in this country, is owing to the humidity of that climate, in which the evaporation is only about half what it is in this country.
The evaporation from a reservoir surface at Baltimore, during the Summer months, was assumed by Colonel Abert to be to the quantity of rain as two to one.
Dr. Holyoke assigns the annual quantity evaporated at Salem, Mass., at fifty-six inches; and Colonel Abert quotes several authorities at Cambridge, Mass., stating the quantity at fifty-six inches. These facts are given by Mr. Blodget, and also the table below.
QUANTITY OF WATER EVAPORATED, IN INCHES, VERTICAL DEPTH.
Whitehaven, England, Ogdensburg, Syracuse, mean of N. Y., N. Y., 6 years 1 yr. 1 year - - Jan. 0.88 1.65 0.67 Feb. 1.04 0.82 1.48 Mar. 1.77 2.07 2.24 Apr. 2.54 1.63 3.42 May. 4.15 7.10 7.31 June. 4.54 6.74 7.60 July. 4.20 7.79 9.08 Aug. 3.40 5.41 6.85 Sept. 3.12 7.40 5.33 Oct. 1.93 3.95 3.02 Nov. 1.32 3.66 1.33 Dec. 1.09 1.15 1.86 - - Year. 30.03 49.37 50.20
The quantity for Whitehaven, England, is reported by J. F. Miller. It was very carefully observed, from 1843 to 1848—the evaporation being from a copper vessel, protected from rain. The district is one of the wettest of England—the mean quantity of rain, for the same time, having been 45.25 inches.
This shows a great difference in the capacity of the air to absorb moisture in England and the United States; and as evaporation is a cooling process, there is greater necessity for under-draining in this country than in England, supposing circumstances in other respects to be similar.
Evaporation takes place at any point of temperature from 32 deg., or lower, to 212 deg.—at which water boils. It is increased by heat, but is not caused solely by it—for a north-west wind in New-England evaporates water, and dries the earth more rapidly than the heat alone of a Summer's day; and when, under ordinary circumstances, evaporation from a water-surface is slow, it becomes quite active when brought in close proximity to sulphuric acid, or other vapor-absorbing bodies.
The cold which follows evaporation is caused by a loss of the heat which is required for evaporation, and which passes off with the vapor, as a solution, in the atmosphere; and as heat leaves the body to aid evaporation, it is evident that that body cannot be cooled by the process, below the dew-point at which evaporation ceases. The popular notion that a body may be cooled almost to the freezing-point, in a hot Summer day, by the action of heat alone, is, then, erroneous. But still, the amount of heat which is used up in evaporating stagnant water from undrained land, that might otherwise go towards warming the land and the roots of crops, is a very serious loss.
The difference in the temperature of a body, resulting from evaporation, may reach 25 deg. in the desert interior of the American continent; but, in the Eastern States, it is not often more than 15 deg..
The temperature of evaporation is the reading of a wet-bulb-thermometer (the bulb being covered with moistened gauze) exposed to the natural evaporation; and the difference between that reading and the reading of a dry-thermometer, is the expression of the cold resulting from evaporation.
When the air is nearly saturated, the temperature of the air rarely goes above 74 deg.; but, if so, the moisture in the air prevents the passing away of insensible perspiration, and the joint action of heat and humidity exhausts the vital powers, causing sun-stroke, as it is called. At New York city, August 12th to 14th, 1853, the wet-thermometer stood at 80 deg. to 84 deg.; the air, at 90 deg. to 94 deg.. The mortality, from this joint effect, was very great—over two hundred persons losing their lives in the two days, in that city.
From very careful observations, made by Lorin Blodget, in 1853, at Washington, it was found that the difference between the wet and dry thermometer was 18-1/2 deg. at 4 P. M., June 30th, and 16 deg. at 2 P. M. on July 1st—the temperature of the air being 98 deg. on the first day, and 95 deg. on the second; but such excesses are unusual.
The following table has been compiled from Mr. Blodget's notice of the peculiarities of the Summer of 1853:
The dates are such as were selected to illustrate the extreme temperatures of the month, and the degrees represent the differences between the wet and dry thermometer. The observations were made at 3 P. M.:
Locality. Dates. Differences.
JUNE, 1853.
Burlington, Vt. 14th to 30th ranged from 8 deg. to 17 deg. Montreal 14th to 30th " 6 to 17 Poultney, Iowa 10th to 30th " 9 to 16 Washington 20th to 30th " 8.5 to 16 Baltimore 13th to 30th " 7.4 to 20.2 Savannah 13th to 30th " 5.2 to 17.3 Austin, Texas 10th to 30th " 4 to 24 Clarkesville, Tenn. 4th to 30th " 10.3 to 20.5
AUGUST.
Bloomfield, N. J. 9th to 14th " 5 to 15 Austin, Texas 6th to 12th " 0 to 19 Philadelphia 10th to 15th " 8 to 14 Jacksonville, Fla. 10th to 15th " 6 to 8
Observations by Lieut. Gillis, at Washington, give mean differences between wet and dry thermometers, from March, 1841, to June, 1842, as follows:
Observations at 3 P. M.:
Jan. Feb. Mar. Apr. May. June. 3 deg..08 4 deg..40 6 deg..47 5 deg..37 7 deg..05 8 deg..03
July. Aug. Sept. Oct. Nov. Dec. 8 deg..89 5 deg..29 5 deg..63 4 deg..61 4 deg..77 2 deg..03
A mean of observations for twenty-five years at the Radcliffe Observatory, Oxford, England, gives a difference between the wet and dry thermometer equal to about two-thirds the difference, as observed by Lieutenant Gillis, at Washington.
On the 12th day of August, 1853, in Austin, Texas, the air was perfectly saturated at a temperature of 76 deg., which was the dew-point, or point of the thermometer at which dew began to form. The dew-point varies according to the temperature and the humidity of the atmosphere; it is usually a few degrees lower than the temperature of evaporation—never higher.
From observations made at Girard College, by Prof. A. D. Bache, in the years 1840 to 1845, we find, that for April, 1844, the dew-point ranged from 4 deg. to 16 deg. lower than the temperature of the air; in May, from 4 deg. to 14 deg. lower; in June, from 6 deg. to 20 deg. lower; in July, from 4 deg. to 17 deg.; in August, from 6 deg. to 15 deg. lower; and in September, from 6 deg. to 21 deg. lower. The dew-point is, then, during the important months of vegetation, within about 20 deg. of the temperature of the air. The temperature of the dew-point, as observed by Prof. Bache, was highest in August, 1843, being 66 deg., and lowest in January, 1844, being 18 deg.; in July, 1844, it was 64 deg., and in February, 1845, it was 25 deg.. Its hourly changes during each day are quite marked, and follow, with some degree of regularity, the changes in the temperature of the air; their greatest departure from each other being at the hottest hour of the day, which is two or three hours after noon, and the least at the coldest hour which is four or five hours after midnight. The average temperature of the dew-point in April, May, and June, 1844, was, at midnight, 50-1/2 deg., air, 57 deg.; five hours after midnight, dew-point, 49 deg., air 54 deg.; three hours after noon, dew-point, 54 deg., air, 63-1/2 deg.. The average temperature for July, August and September, was, at midnight, dew-point, 58-1/2 deg., air, 65 deg.; five hours after midnight, dew-point, 58 deg., air, 62 deg.; three hours after noon, dew-point, 60-1/2 deg., air, 78 deg.. The average temperature for the year was, at midnight, dew-point, 42 deg., air, 48 deg.; five hours after midnight, dew-point, 41 deg., air, 46 deg.; three hours after noon, dew-point, 44-1/2 deg., air, 59 deg..
The relative humidity of the atmosphere, or the amount of vapor held in suspension in the air, in proportion to the amount which it might hold, was, in the year 1858, as given in the journal of the Franklin Institute, for
Philadelphia. Somerset Co. April 49 per cent. — 2 P. M. May 59 " 72 " June 55 " 63 " July 50 " 61 " August 55 " 58 " September 50 " 57 "
The saturation often falls to 30 per cent., but with great variability. Evaporation goes on most rapidly when the per centage of saturation is lowest; and, as before observed, the cause of the excess of evaporation in this country over that of England is the excessive humidity of that climate and the dryness of this. It has also been said that there is greater need for drainage in the United States on this account; and, as the warmth induced by draining is somewhat, in its effect, a merchantable product, it may be well to consider it for a moment in that light.
First: The drained land comes into condition for working, a week or ten days earlier in the Spring than other lands.
Secondly: The growth of the crops is quickened all through the Summer by an increase of several degrees in the temperature of the soil.
Thirdly: The injurious effects of frost are kept off several days later in the Fall.
Of the value of these conditions, the farmer, who has lost his crops for lack of a few more warm days, may make his own estimates. In Roxbury, Mr. I. P. Rand heats up a portion of his land, for the purpose of raising early plants for the market, by means of hot water carried by iron pipes under the surface of the ground. In this manner he heats an area equal to 100 feet by 12 feet, by burning about one ton of coal a month. The increase of temperature which, in this case, is caused by that amount of coal, can, in the absence of direct measurement, only be estimated; but it, probably, will average about 30 deg., day and night, throughout the month. In an acre the area is 36.4 times as great as that heated by one ton of coal; the cost being in direct proportion to the area, 36.4 tons of coal would be required to heat an acre; which, at $6 per ton, would cost $217.40. To heat an acre through 10 deg., would cost, then, $72.47. It may be of interest to consider how much coal would be required to evaporate from an undrained field that amount of water which might be carried off by under-drains, but which, without them, is evaporated from the surface. It may be taken as an approximate estimate, that the evaporation from the surface of an undrained retentive field, is equal to two inches vertical depth of water for each of the months of May, June, July, and August; which is equal to fifty-four thousand three hundred and five gallons, or eight hundred and sixty-two hogsheads per acre for each month. If this quantity of water were evaporated by means of a coal fire, about 22-2/3 tons of coal would be consumed, which, at $6 a ton, would cost $136. The cost of evaporating the amount of water which would pass off in one day from an acre would be about $4.53. It is probable that about half as much water would be evaporated from thorough-drained land, though, by some experiments, the proportion has been made greater—in which case the loss of heat resulting from an excess of moisture evaporated from undrained retentive land, over that which would be evaporated from drained land, would be equal to that gained by 11-1/3 tons of coal, which would cost $68; and this for each acre, in each of the three months. At whatever temperature a liquid vaporizes, it absorbs the same total quantity of heat.
The latent heat of watery vapor at 212 deg. is 972 deg.; that is, when water at 212 deg. is converted into vapor at the same temperature, the amount of heat expended in the process is 972 deg.. This heat becomes latent, or insensible to the thermometer. The heat rendered latent by converting ice into water is about 140 deg.. There are 7.4805 gallons in a cubic foot of water which weighs 62.38 lbs."
We have seen that a sea of water, more than three feet deep over the whole face of the land, falls annually from the clouds, equal to 4,000 tons in weight to every acre. We would use enough of this water to dissolve the elements of fertility in the soil, and fit them for the food of plants. We would retain it all in our fields, long enough to take from it its stores of fertilizing substances, brought from reeking marshes and steaming cities on cloud-wings to our farms. We would, after taking enough of its moisture to cool the parched earth, and to fit the soil for germination and vegetable growth, discharge the surplus, which must otherwise stagnate in the subsoil, by rapid drainage into the natural streams and rivers.
Evaporation proceeds more rapidly from a surface of water, than from a surface of land, unless it be a saturated surface. It proceeds more rapidly in the sun than in the shade, and it proceeds again more rapidly in warm than in cold weather. It varies much with the culture of the field, whether in grass, or tillage, or fallow, and with its condition, as to being dry or wet, and with its formation, whether level or hilly. Yet, with all these variations, very great reliance may be placed upon the ascertained results of the observations already at our command.
We have seen that evaporation from a water surface is, in general, greater than from land, and here we may observe one of those grand compensating designs of Providence which exist through all nature.
If the same quantity of water fell upon the sea and the land, and the evaporation were the same from both, then all the rivers running into the sea would soon convey to it all the water, and the sea would be full. But though nearly as much water falls on the sea as on the land, yet evaporation is much greater from the water than from land.
About three feet of rain falls upon the water, while the evaporation from a water surface far exceeds that amount. In the neighborhood of Boston, evaporation from water surface is said to be 56 inches in the year, and in the State of New York, about 50 inches; while, in England, it is put by Mr. Dalton at 44.43 inches, and, by others, much lower.
Again, about three feet of water annually falls upon the land, while the evaporation from the land is but little more than 20 inches. If this water fell upon a flat surface of soil, with an impervious subsoil of rock or clay, we should have some sixteen inches of water in the course of the year more than evaporates from the land. If a given field be dish-shaped, so as to retain it all, it must become a pond, and so remain, except in Summer, when greater evaporation from a water surface may reduce it to a swamp or marsh.
With 16 or 18 inches more water falling annually on all our cultivated fields than goes off by evaporation, is it not wise to inquire by what process of Nature or art this vast surplus shall escape?
Experiments have been made with a view to determine the proportion of evaporation and filtration, upon well-drained land, in different months. From an able article in the N. Y. Agricultural Society for 1854, by George Geddes, we copy the following statement of valuable observations upon these points.
It will be observed that, in the different observations collected in this chapter, results are somewhat various. They have been brought together for comparison, and will be found sufficiently uniform for all practical purposes in the matter of drainage.
"The experiments upon evaporation and drainage, made on Mr. Dalton's plan, were in vessels three feet deep, filled with soil just in the condition to secure perfect freedom from excess of water, and the drainage was determined by the amount of water that passed out of the tube at the bottom. These experiments have been most perfectly made in England by Mr. John Dickinson. The following table exhibits the mean of eight years:
====================================================================== YEAR. October to March. April to September. Total each year. - Rain. Filtra- [%] Rain. Filtra- [%] Rain. Filtra- [%] tion. tion. tion. - 1836 18.80 15.55 82.7 12.20 2.10 17.3 31.00 17.65 56.9 1837 11.30 6.85 60.6 9.80 0.10 1.0 21.10 6.95 32.9 1838 12.32 8.45 68.8 10.81 0.12 1.2 23.13 8.57 37.0 1839 13.87 12.31 88.2 17.41 2.60 15.0 31.28 14.91 47.6 1840 11.76 8.19 69.6 9.68 0.00 0.0 21.44 8.19 38.2 1841 16.84 14.19 84.2 15.26 0.00 0.0 32.10 14.19 44.2 1842 14.28 10.46 73.2 12.15 1.30 10.7 26.43 11.76 44.4 1843 12.43 7.11 57.2 14.04 0.99 7.1 26.47 8.10 36.0 - Mean 13.95 10.39 74.5 12.67 0.90 7.1 26.61 11.29 42.4 ====================================================================== Legend: [%] = Per cent filtered.
"A soil that holds no water for the use of plants below six inches, will suffer from drouth in ten days in June, July, or August. If the soil is in suitable condition to hold water to the depth of three feet, it would supply sufficient moisture for the whole months of June, July, and August.
"M. de la Hire has shown that, at Paris, a vessel, sixteen inches deep, filled with sand and loam, discharged water through the pipe at the bottom until the 'herbs' were somewhat grown, when the discharge ceased, and the rains were insufficient, and it was necessary to water them. The fall of water at Paris is stated, in this account, at twenty inches in the year, which is less than the average, and the experiment must have been made in a very dry season; but the important point proved by it is, that the plants, when grown up, draw largely from the ground, and thereby much increase the evaporation from a given surface of earth. The result of the experiment is entirely in accordance with what would have been expected by a person conversant with the laws of vegetation.
"The mean of each month for the eight years is:
============================================== Per cent MONTHS. Rain. Filtration. filtered. -+ -+ -+ Inches. Inches. January 1.84 1.30 70.7 February 1.79 1.54 78.4 March 1.61 1.08 66.6 April 1.45 0.30 21.0 May 1.85 0.11 5.8 June 2.21 0.04 1.7 July 2.28 0.04 1.8 August 2.42 0.03 1.4 September 2.64 0.37 13.9 October 2.82 1.40 49.5 November 3.83 3.26 84.9 December 1.64 1.80 110.0 ==============================================
"The filtration from April to September is very small—practically nothing; but during those months we have 12.67 inches of rain—that is, we have two inches a month for evaporation besides the quantity in the earth on the first day of April. From October to March we have 10.39 inches filtered out of 13.95 inches, the whole fall. 'Of this Winter portion of 10.39, we must allow at least six inches for floods running away at the time of the rain, and then we have only 4.39 inches left for the supply of rivers and wells.' (Breadmore, p. 34.)
"It is calculated in England that the ordinary Summer run of streams does not exceed ten cubic feet per minute per square mile, and that the average for the whole year, due to springs and ordinary rains, is twenty feet per minute per square mile, exclusive of floods—and assuming no very wet or high mountain districts (Breadmore, p. 34)—which is equal to about four inches over the whole surface. If we add to this the six inches that are supposed to run off in freshets, we have ten inches discharged in the course of the year by the streams. The whole filtration was 11.29 inches—10.39 in the Winter, and .90 in the Summer. The remainder, 1.29 inches, is supposed to be consumed by wells and excessive evaporation from marshes and pools, from which the discharge is obstructed, by animals, and in various other ways. These calculations were made from experiments running through eight years, in which the average fall of water was only 26.61 inches per annum. When the results derived from them are applied to our average fall of 35.28 inches, we have for the water that constitutes the Summer flow of our streams 13.25 cubic feet per minute per mile of the country drained, and for the average annual flow, exclusive of freshets, 26.50 cubic feet per mile per minute. That is to say, of the 35.28 inches of water that fall in the course of the year, 5.30 run away in the streams as the average annual flow, 7.95 run away in the freshets, and 20.47 evaporate from the earth's surface, leaving 1.56 for consumption in various ways. In the whole year the drainage is nearly equal to one cubic foot per second per square mile (.976), no allowance being made for the 1.56 inches which is lost as before stated. These calculations are based upon English experiments. Mr. McAlpine, late State engineer and surveyor, in making his calculations for supplying the city of Albany with water (page 22 of his Report to the Water Commissioners), takes 45 per cent of the fall as available for the use of the city. Mr. Henry Tracy, in his Report to the Canal Board of 1849 (page 17), gives the results of the investigations in the valleys of Madison Brook, in Madison County, and of Long Pond, near Boston, Mass., as follows:
========================================================================== Name Fall of rain Water ran off Evaporation Ratio YEAR. of and snow in from surface of valley. in valley. inches. of ground. drainage. + + -+ + - 1835 Madison Brook 35.26 15.83 19.43 0.449 + -+ + -+ + - 1837 Long Pond 26.65 11.70 14.95 0.439 + -+ + -+ + - 1838 Do 38.11 16.62 21.49 0.436 + -+ + -+ + - Mean 0.441 ==========================================================================
"Madison Brook drains 6,000 acres, and Long Pond 11,400 acres. Mr. Tracy makes the following comment on this table: 'It appears that the evaporation from the surface of the ground in the valley of Long Pond was about 44 per cent more in 1838 than it was in 1837, while the ratio of the drainage differed less than one per cent the same years.'
"Dr. Hale states the evaporation from water-surface at Boston to be 56 inches in a year. (Senate Doc., No. 70, for 1853.)
"The following table contains the results arrived at by Mr. Coffin, at Ogdensburgh, and Mr. Conkey, at Syracuse, in regard to the evaporation from water-surface:
============================================================= COFFIN, at Ogdensburgh, CONKEY, at Syracuse, in 1838. in 1852. MONTHS. - Rain. Evaporation. Rain. Evaporation. - - January 2.36 1.652 3.673 0.665 February 0.97 0.817 1.307 1.489 March 1.18 2.067 3.234 2.239 April 0.40 1.625 3.524 3.421 May 4.81 7.100 4.491 7.309 June 3.57 6.745 3.773 7.600 July 1.88 7.788 2.887 9.079 August 2.55 5.415 2.724 6.854 September 1.01 7.400 2.774 5.334 October 2.73 3.948 4.620 3.022 November 2.07 3.659 4.354 1.325 December 1.08 1.146 4.112 1.863 - - TOTAL 24.61 49.362 41.473 50.200 =============================================================
"The annual fall of water in England, is stated, by Mr. Dalton, to be 32 inches. In this State, it is 35.28 inches. The evaporation from water-surface in England, is put, by Mr. Dalton, at 44.43 inches. The fall is less, and the evaporation is less, in England than here; and the fall, in each case, bears the same proportion to the evaporation, very nearly; and it appears that the experiments made on the two sides of the ocean, result in giving very nearly the same per centage of drainage. In England, it is 42.4 per cent.; in this State, it is 44.1. In England, the experiments were made on a limited scale compared with ours; but the results agree so well, that great confidence may safely be placed in them."
In reviewing the whole subject of rain, and of evaporation and filtration, we seem to have evidence to justify the opinion, that with considerable more rain in this country than in England, and with a greater evaporation, because of a clearer sky and greater heat, we have a larger quantity of surplus water to be disposed of by drainage.
The occasion for thorough-drainage, however, is greater in the Northern part of the United States than in England, upon land of the same character; because, as we have already seen, rain falls far more regularly there than here, and never in such quantities in a single day; and because there the land is open to be worked by the plough nearly every day in the year, while here for several months our fields are locked up in frost, and our labor for the Spring crowded into a few days. There, the water which falls in Winter passes into the soil, and is drained off as it falls; while here, the snow accumulates to a great depth, and in thawing floods the land at once.
Both here and in England, much of the land requires no under-draining, as it has already a subsoil porous enough to allow free passage for all the surplus water; and it is no small part of the utility of understanding the principles of drainage, that it will enable farmers to discriminate—at a time when draining is somewhat of a fashionable operation with amateurs—between land that does and land that does not require so expensive an operation.
CHAPTER IV.
DRAINAGE OF HIGH LANDS—WHAT LANDS REQUIRE DRAINAGE.
What is High Land?—Accidents to Crops from Water.—Do Lands need Drainage in America?—Springs.—Theory of Moisture, with Illustrations.—Water of Pressure.—Legal Rights as to Draining our Neighbor's Wells and Land.—What Lands require Drainage?—Horace Greeley's Opinion.—Drainage more Necessary in America than in England; Indications of too much Moisture.—Will Drainage Pay?
By "high land," is meant land, the surface of which is not overflowed, as distinguished from swamps, marshes, and the like low lands. How great a proportion of such lands would be benefitted by draining, it is impossible to estimate.
The Committee on Draining, in their Report to the State Agricultural Society of New York, in 1848, assert that, "There is not one farm out of every seventy-five in this State, but needs draining—yes, much draining—to bring it into high cultivation. Nay, we may venture to say, that every wheat-field would produce a larger and finer crop if properly drained." The committee further say: "It will be conceded, that no farmer ever raised a good crop of grain on wet ground, or on a field where pools of water become masses of ice in the Winter. In such cases, the grain plants are generally frozen out and perish; or, if any survive, they never arrive at maturity, nor produce a well-developed seed. In fact, every observing farmer knows that stagnant water, whether on the surface of his soil, or within reach of the roots of his plants, always does them injury."
The late Mr. Delafield, one of the most distinguished agriculturists of New York, said in a public address:
"We all well know that wheat and other grains, as well as grasses, are never fully developed, and never produce good seed, when the roots are soaked in moisture. No man ever raised good wheat from a wet or moist subsoil. Now, the farms of this country, though at times during the Summer they appear dry, and crack open on the surface, are not, in fact, dry farms, for reasons already named. On the contrary, for nine months out of twelve, they are moist or wet; and we need no better evidence of the fact, than the annual freezing out of the plants, and consequent poverty of many crops."
If we listen to the answers of farmers, when asked as to the success of their labors, we shall be surprised, perhaps, to observe how much of their want of success is attributed to accidents, and how uniformly these accidents result from causes which thorough draining would remove. The wheat-crop of one would have been abundant, had it not been badly frozen out in the Fall; while another has lost nearly the whole of his, by a season too wet for his land. A farmer at the West has planted his corn early, and late rains have rotted the seed in the ground; while one at the East has been compelled, by the same rains, to wait so long before planting, that the season has been too short. Another has worked his clayey farm so wet, because he had not time to wait for it to dry, that it could not be properly tilled. And so their crops have wholly or partially failed, and all because of too much cold water in the soil. It would seem, by the remarks of those who till the earth, as if there were never a season just right—as if Providence had bidden us labor for bread, and yet sent down the rains of heaven so plentifully as always to blight our harvests. It is rare that we do not have a most remarkable season, with respect to moisture, especially. Our potatoes are rotted by the Summer showers, or cut off by a Summer drought; and when, as in the season of 1856, in New England, they are neither seriously diseased nor dried up, we find at harvest-time that the promise has belied the fulfillment; that, after all the fine show above ground, the season has been too wet, and the crop is light. We frequently hear complaint that the season was too cold for Indian corn, and that the ears did not fill; or that a sharp drought, following a wet Spring, has cut short the crop. We hear no man say, that he lacked skill to cultivate his crop. Seldom does a farmer attribute his failure to the poverty of his soil. He has planted and cultivated in such a way, that, in a favorable season, he would have reaped a fair reward for his toil; but the season has been too wet or too dry; and, with full faith that farming will pay in the long run, he resolves to plant the same land in the same manner, hoping in future for better luck.
Too much cold water is at the bottom of most of these complaints of unpropitious seasons, as well as of most of our soils; and it is in our power to remove the cause of these complaints and of our want of success.
"The fault, dear Brutus, is not in our stars, But in ourselves."
We must underdrain all the land we cultivate, that Nature has not already underdrained, and we shall cease complaints of the seasons. The advice of Cromwell to his soldiers: "Trust God, and keep your powder dry," affords a good lesson of faith and works to the farmer. We shall seldom have a season, upon properly drained land, that is too wet, or too cold, or even too dry; for thorough draining is almost as sure a remedy for a drought, as for a flood.
Do lands need under draining in America? It is a common error to suppose that, because the sun shines more brightly upon this country than upon England, and because almost every Summer brings such a drought here as is unknown there, her system of thorough drainage can have no place in agriculture on this side of the Atlantic. It is true that we have a clearer sky and a drier climate than are experienced in England; but it is also true that, although we have a far less number of showers and of rainy days, we have a greater quantity of rain in the year.
The necessity of drainage, however, does not depend so much upon the quantity of water which falls or flows upon land, nor upon the power of the sun to carry it off by evaporation, as upon the character of the subsoil. The vast quantity of water which Nature pours upon every acre of soil annually, were it all to be removed by evaporation alone, would render the whole country barren; but Nature herself has kindly done the work of draining upon a large proportion of our land, so that only a healthful proportion of the water which falls on the earth, passes off at the surface by the influence of the sun.
If the subsoil is of sand or gravel, or of other porous earth, that portion of the water not evaporated, passes off below by natural drainage. If the subsoil be of clay, rock, or other impervious substances, the downward course of the water is checked, and it remains stagnant, or bursts out upon the surface in the form of springs.
As the primary object of drainage is to remove surplus water, it may be well to consider with some care
THE SOURCES OF MOISTURE.
Springs.—These are, as has been suggested, merely the water of rain and snow, impeded in its downward percolation, and collected and poured forth in a perennial flow at a lower level.
The water which falls in the form of rain and snow upon the soil of the whole territory of the United States, east of the Rocky Mountains, each year, is sufficient to cover it to the depth of more than 3 feet. It comes upon the earth, not daily in gentle dews to water the plants, but at long, unequal intervals, often in storms, tempests, and showers, pouring out, sometimes, in a single day, more than usually falls in a whole month.
What becomes of all this moisture, is an inquiry especially interesting to the agriculturist, upon whose fruitful fields this flood of water annually descends, and whose labor in seed-time would be destroyed by a single Summer shower, were not Nature more thoughtful than he, of his welfare. Of the water which thus falls upon cultivated fields, a part runs away into the streams, either upon the surface, or by percolation through the soil; a part is taken up into the air by evaporation, while a very small proportion enters into the constitution of vegetation. The proportion which passes off by percolation varies according to the nature of the soil in the locality where it falls.
Usually, we find the crust of the earth in our cultivated fields, in strata, or layers: first, a surface-soil of a few inches of a loamy nature, in which clay or sand predominates; and then, it may be, a layer of sand or gravel, freely admitting the passage of water; and, perhaps, next, and within two or three feet of the surface, a stratum of clay, or of sand or gravel cemented with some oxyd of iron, through which water passes very slowly, or not at all. These strata are sometimes regular, extending at an equal depth over large tracts, and having a uniform dip, or inclination. Oftener, however, in hilly regions especially, they are quite irregular—the impervious stratum frequently having depressions of greater or less extent, and holding water, like a bowl. Not unfrequently, as we cut a ditch upon a declivity, we find that the dip of the strata below has no correspondence with the visible surface of the field, but that the different strata lie nearly level, or are much broken, while the surface has a regular inclination.
Underlying all soils, at greater or less depth, is found some bed of rock, or clay, impervious to water, usually at but few feet below the surface—the descending water meeting with obstacles to its regular descent. The tendency of the rain-water which falls upon the earth, is to sink directly downward by gravitation. Turned aside, however, by the many obstacles referred to, it often passes obliquely, or almost horizontally, through the soil. The drop which falls upon the hill-top sinks, perhaps, a few inches, meets with a bed of clay, glides along upon it for many days, and is at last borne out to be drunk up by the sun on some far-off slope; another, falling upon the sand-plain, sinks at once to the "water-line," or line of level water, which rests on clay beneath, and, slowly creeping along, helps to form a swamp or bog in the valley.
Sometimes, the rain which falls upon the high land is collected together by fissures in the rocks, or by seams or ruptures in the impervious strata below the surface, and finds vent in a gushing spring on the hill-side.
We feel confident that no better illustration of the theory of springs, as connected with our subject, can be found, than that of Mr. Girdwood, in the Cyclopedia of Agriculture—a work from which we quote the more liberally, because it is very expensive and rare in America:
"When rain falls on a tract of country, part of it flows over the surface, and makes its escape by the numerous natural and artificial courses which may exist, while another portion is absorbed by the soil and the porous strata which lie under it.
"Let the following diagram represent such a tract of country, and let the dark portions represent clay or other impervious strata, while the lighter portions represent layers of gravel, sand, or chalk, permitting a free passage to water.
"When rain falls in such a district, after sinking through the surface-layer (represented in the diagram by a narrow band), it reaches the stratified layers beneath. Through these it still further sinks, if they are porous, until it reaches some impervious stratum, which arrests its directly-downward course, and compels it to find its way along its upper surface. Thus, the rain which falls on the space represented between B and D, is compelled, by the impervious strata, to flow towards C. Here it is at once absorbed, but is again immediately arrested by the impervious layer E; it is, therefore, compelled to pass through the porous stratum C, along the surface of E to A, where it pours forth in a fountain, or forms a morass or swamp, proportionate in size or extent to the tract of country between B and D, or the quantity of rain which falls upon it. In such a case as is here represented, it will be obvious that the spring may often be at a great distance from the district from which it derives its supplies; and this accounts for the fact, that drainage-works on a large scale sometimes materially lessen the supply of water at places remote from the scene of operations.
"In the instance given above, the water forming the spring is represented as gaining access to the porous stratum, at a point where it crops out from beneath an impervious one, and as passing along to its point of discharge at a considerable depth, and under several layers of various characters. Sometimes, in an undulating country, large tracts may rest immediately upon some highly-porous stratum—as from B to C, in the following diagram—rendering the necessity for draining less apparent; while the country from A to B, and from C to D, may be full of springs and marshes—arising, partly, from the rain itself, which falls in these latter districts, being unable to find a way of escape, and partly from the natural drainage of the more porous soils adjoining being discharged upon it.
"Again: the rocks lying under the surface are sometimes so full of fissures, that, although they themselves are impervious to water, yet, so completely do these fissures carry off rain, that, in some parts of the county of Durham, they render the sinking of wells useless, and make it necessary for the farmers to drive their cattle many miles for water. It sometimes happens that these fissures, or cracks, penetrate to enormous depths, and are of great width, and filled with sand or clay. These are termed faults by miners; and some, which we lately examined, at distances of from three to four hundred yards from the surface, were from five to fifteen yards in width. These faults, when of clay, are generally the cause of springs appearing at the surface: they arrest the progress of the water in some of the porous strata, and compel it to find an exit, by passing to the surface between the clay and the faces of the ruptured strata. When the fault is of sand or gravel, the opposite effect takes place, if it communicates with any porous stratum; and water, which may have been flowing over the surface, on reaching it, is at once absorbed. In the following diagram, let us suppose that B represents such a clay-fault as has been described, and that A represents a sandy one, and that C and D represent porous strata charged with water. On the water reaching the fault at B, it will be compelled to find its way to the surface—there forming a spring, and rendering the retentive soil, from B to A, wet; but, as soon as it reaches the sandy-fault at A, it is immediately absorbed, and again reaches the porous strata, along which it had traveled before being forced to the surface at B. It will be observed, that the strata at the points of dislocation are not represented as in a line with the portions from which they have been dissevered. This is termed the upthrow of the fault, as at B; and the downthrow, as at A. For the sake of the illustration, the displacement is here shown as very slight; but, in some cases, these elevations and depressions of the strata extend to many hundreds of feet—as, for instance, at the mines of the British Iron Company, at Cefn-Mawre, in North Wales, where the downthrow of the fault is 360 feet.
"Sometimes the strata are disposed in the form of a basin. In this case, the water percolating through the more elevated ground—near what may be called the rim—collects in the lower parts of the strata towards the centre, there forcing its way to the surface, if the upper impervious beds be thin; or, if otherwise, remaining a concealed reservoir, ready to yield its supplies to the shaft or boring-rod of the well-sinker, and sometimes forming a living fountain capable of rising many feet above the surface. It is in this way that what are called Artesian wells are formed. The following diagram represents such a disposition of the strata as has just been referred to. The rain which falls on the tracts of country at A and B, gradually percolates towards the centre of the basin, where it may be made to give rise to an Artesian well, as at C, by boring through the superincumbent mass of clay; or it may force itself to the surface through the thinner part of the layer of clay, as at D—there forming a spring, or swamp.
"Again: the higher parts of hilly ground are sometimes composed of very porous and absorbent strata, while the lower portions are more impervious—the soil and subsoil being of a very stiff and retentive description. In this case, the water collected by the porous layers is prevented from finding a ready exit, when it reaches the impervious layers, by the stiff surface-soil. The water is by this means dammed up in some measure, and acquires a considerable degree of pressure; and, forcing itself to the day at various places, it forms those extensive "weeping"-banks which have such an injurious effect upon many of our mountain-pastures. This was the form of spring, or swamp, to the removal of which Elkington principally turned his attention; and the following diagram, taken from a description of his system of draining, will explain the stratification and springs referred to, more clearly.
"In some districts, where clay forms the staple of the soil, a bed of sand or gravel, completely saturated with water, occurs at the depth of a few feet from the surface, following all the undulations of the country, and maintaining its position, in relation to the surface, over considerable tracts, here and there pouring forth its waters in a spring, or denoting its proximity, by the subaquatic nature of the herbage. Such a configuration is represented in the following diagram, where A represents the surface-soil; B, the impervious subsoil of clay; C, the bed of sandy-clay or gravel; and D, the lower bed of clay, resting upon the rocky strata beneath.
"Springs sometimes communicate with lakes or pools, at higher levels. In such cases, the quantity of water discharged is generally so great, as to form at once a brook or stream of some magnitude. These, therefore, hardly come under the ordinary cognizance of the land-drainer, and are, therefore, here merely referred to."
THE WATER OF PRESSURE.
Water that issues from the land, either constantly, periodically, or even intermittently, may, perhaps, be properly termed a spring. But there is often much water in the soil which did not fall in rain upon that particular field, and which does not issue from it in any defined stream, but which is slowly passing through it by percolation from a higher source, to ooze out into some stream, or to pass off by evaporation; or, perhaps, farther on, to fall into crevices in the soil, and eventually form springs. As we find it in our field, it is neither rain-water, which has there fallen, nor spring-water, in any sense. It has been appropriately termed the water of pressure, to distinguish it from both rain and spring-water; and the recognition of this term will certainly be found convenient to all who are engaged in the discussion of drainage.
The distinction is important in a legal point of view, as relating to the right of the land-owner to divert the sources of supply to mill-streams, or to adjacent lower lands. It often happens that an owner of land on a slope may desire to drain his field, while the adjacent owner below, may not only refuse to join in the drainage, but may believe that he derives an advantage from the surface-washing or the percolation from his higher neighbor. He may believe that, by deep drainage above, his land will be dried up and rendered worthless; or, he may desire to collect the water which thus percolates, into his land, and use it for irrigation, or for a water-ram, or for the supply of his barn-yard. May the upper owner legally proceed with the drainage of his own land, if he thus interfere with the interests of the man below?
Again: wherever drains have been opened, we already hear complaints of their effects upon wells. In our good town of Exeter, there seems to be a general impression on one street, that the drainage of a swamp, formerly owned by the author, has drawn down the wells on that street, situated many rods distant from the drains. Those wells are upon a sandy plain, with underlying clay, and the drains are cut down upon the clay, and into it, and may possibly draw off the water a foot or two lower through the whole village—if we can regard the water line running through it as the surface of a pond, and the swamp as a dam across its outlet.
The rights of land-owners, as to running water over their premises, have been fruitful of litigation, but are now well defined. In general, in the language of Judge Story,
"Every proprietor upon each bank of a river, is entitled to the land covered with water in front of his bank to the middle thread of the stream, &c. In virtue of this ownership, he has a right to the use of the water flowing over it in its natural current, without diminution or obstruction. The consequence of this principle is, that no proprietor has a right to use the water to the prejudice of another. It is wholly immaterial whether the party be a proprietor above or below, in the course of the river, the right being common to all the proprietors on the river. No one has a right to diminish the quantity which will, according to the natural current, flow to the proprietor below, or to throw it back upon a proprietor above."
Chief Justice Richardson, of New Hampshire, thus briefly states the same position:
"In general, every man has a right to the use of the water flowing in a stream through his land, and if any one divert the water from its natural channel, or throw it back, so as to deprive him of the use of it, the law will give him redress. But one man may acquire, by grant, a right to throw the water back upon the land of another, and long usage may be evidence of such a grant. It is, however, well settled that a man acquires no such right by merely being the first to make use of the water."
We are not aware that it has ever been held by any court of law, or even asserted, that a land-owner may not intercept the percolating water in his soil for any purpose and at his pleasure; nor have we in mind any case in which the draining out of water from a well, by drainage for agricultural purposes, has subjected the owner of the land to compensation.
It is believed that a land-owner has the right to follow the rules of good husbandry in the drainage of his land, so far as the water of pressure is concerned, without responsibility for remote consequences to adjacent owners, to the owners of distant wells or springs that may be affected, or to mill-owners.
In considering the effect of drainage on streams and rivers, it appears that the results of such operations, so far as they can be appreciated, are, to lessen the value of water powers, by increasing the flow of water in times of freshets, and lessening it in times of drought. It is supposed in this country, that clearing the land of timber has sensibly affected the value of "mill privileges," by increasing evaporation, and diminishing the streams. No mill-owner has been hardy enough to contend that a land-owner may not legally cut down his own timber, whatever the effect on the streams. So, we trust, no court will ever be found, which will restrict the land-owner in the highest culture of his soil, because his drainage may affect the capacity of a mill-stream to turn the water-wheels.
To return from our digression. It is necessary, in order to a correct apprehension of the work which our drains have to perform, to form a correct opinion as to how much of the surplus moisture in our field is due to each of the three causes to which we have referred—to wit, rain-water, which falls upon it; springs, which burst up from below; and water of pressure, stagnant in, or slowly percolating through it. The rain-tables will give us information as to the first; but as to the others, we must form our opinion from the structure of the earth around us, and observation upon the field itself, by its natural phenomena and by opening test-holes and experimental ditches. Having gained accurate knowledge of the sources of moisture, we may then be able to form a correct opinion whether our land requires drainage, and of the aid which Nature requires to carry off the surplus water.
WHAT LANDS REQUIRE DRAINAGE?
The more one studies the subject of drainage, the less inclined will he be to deal in general statements. "Do you think it is profitable to underdrain land?" is a question a thousand times asked, and yet is a question that admits of no direct general answer. Is it profitable to fence land? is it profitable to plow land? are questions of much the same character. The answers to them all depend upon circumstances. There is land that may be profitably drained, and fenced, and plowed, and there is a great deal that had better be let alone. Whether draining is profitable or not, depends on the value and character of the land in question, as well as on its condition as to water. Where good land is worth one hundred dollars an acre, it might be profitably drained; when, if the same land were worth but the Government price of $1.25 an acre, it might be better to make a new purchase in the neighborhood, than to expend ten times its value on a tract that cannot be worth the cost of the operation. Drainage is an expensive operation, requiring much labor and capital, and not to be thought of in a pioneer settlement by individual emigrants. It comes after clearing, after the building of log-houses and mills, and schoolhouses, and churches, and roads, when capital and labor are abundant, and when the good lands, nature-drained, have been all taken up.
And, again, whether drainage is profitable, depends not only on the value, but on the character of the soil as to productiveness when drained. There is much land that would be improved by drainage, that cannot be profitably drained. It would improve almost any land in New England to apply to it a hundred loads of stable manure to the acre; but whether such application would be profitable, must depend upon the returns to be derived from it. Horace Greeley, who has his perceptions of common affairs, and especially of all that relates to progress, wide awake, said, in an address at Peekskill, N. Y.:
"My deliberate judgment is, that all lands which are worth plowing, which is not the case with all lands that are plowed, would be improved by draining; but I know that our farmers are neither able nor ready to drain to that extent, nor do I insist that it would pay while land is so cheap, and labor and tile so dear as at present. Ultimately, I believe, we shall tile-drain nearly all our level, or moderately sloping lands, that are worth cultivation."
Whether land would be improved by drainage, is one question, and whether the operation will pay, is quite another. The question whether it will pay, depends on the value of the land before drainage, the cost of the operation, and the value of the land when completed. And the cost of the operation includes always, not only the money and labor expended in it, but also the loss to other land of the owner, by diverting from it the capital which would otherwise be applied to it. Where labor and capital are limited so closely as they are in all our new States, it is a question not only how can they be profitably applied, but how can they be most profitably applied. A proprietor, who has money to loan at six per cent. interest, may well invest it in draining his land; when a working man, who is paying twelve per cent. interest for all the capital he employs, might ruin himself by making the same improvement.
DO ALL LANDS REQUIRE DRAINAGE?
Our opinion is, that a great deal of land does not in any sense require drainage, and we should differ with Mr. Greeley, in the opinion that all lands worth ploughing, would be improved by drainage. Nature has herself thoroughly drained a large proportion of the soil. There is a great deal of finely-cultivated land in England, renting at from five to ten dollars per acre, that is thought there to require no drainage.
In a published table of estimates by Mr. Denton, made in 1855, it is supposed that Great Britain, including England, Scotland, and Wales, contain 43,958,000 acres of land, cultivated and capable of cultivation; of which he sets down as "wet land," or land requiring drainage, 22,890,004 acres, or about one half the whole quantity. His estimate is, that only about 1,365,000 acres had then been permanently drained, and that it would cost about 107 millions of pounds to complete the operation, estimating the cost at about twenty shillings, or five dollars per acre.
These estimates are valuable in various views of our subject. They answer with some definiteness the question so often asked, whether all lands require drainage, and they tend to correct the impression, which is prevalent in this country, that there is something in the climate of Great Britain that makes drainage there essential to good cultivation on any land. The fact is not so. There, as in America, it depends upon the condition and character of the soil, more than upon the quantity of rain, or any condition of climate, whether drainage is required or not. Generally, it will be found on investigation, that so far as climate, including of course the quantity and regularity of the rain-fall, is concerned, drainage is more necessary in America than in Great Britain—the quantity of rain being in general greater in America, and far less regular in its fall. This subject, however, will receive a more careful consideration in another place.
If in America, as in Great Britain, one half the cultivable land require drainage, or even if but a tenth of that half require it, the subject is of vast importance, and it is no less important for us to apprehend clearly what part of our land does not require this expenditure, than to learn how to treat properly that which does require it.
To resume the inquiry, what lands require drainage? it may be answered—
ALL LANDS OVERFLOWED IN SUMMER REQUIRE DRAINAGE.
Lands overflowed by the regular tides of the ocean require drainage, whether they lie upon the sea-shore, or upon rivers or bays. But this drainage involves embankments, and a peculiar mode of procedure, of which it is not now proposed to treat.
Again, all lands overflowed by Summer freshets, as upon rivers and smaller streams, require drainage. These, too, usually require embankments, and excavations of channels or outlets, not within the usual scope of what is termed thorough drainage. For a further answer to the question—what lands require drainage? the reader is referred to the chapters which treat of the effect of drainage upon the soil.
SWAMPS AND BOGS REQUIRE DRAINAGE.
No argument is necessary to convince rational men that the very extensive tracts of land, which are usually known as swamps and bogs, must, in some way, be relieved of their surplus water, before they can be rendered fit for cultivation. The treatment of this class of wet lands is so different from that applied to what we term upland, that it will be found more convenient to pass the subject by with this allusion, at present, and consider it more systematically under a separate head.
ALL HIGH LANDS THAT CONTAIN TOO MUCH WATER AT ANY SEASON, REQUIRE DRAINAGE.
Draining has been defined, "The art of rendering land not only so free of moisture as that no superfluous water shall remain in it, but that no water shall remain in it so long as to injure, or even retard the healthy growth of plants required for the use of man and beast."
Some plants grow in water. Some even spring from the bottom of ponds, and have no other life than such a position affords. But most plants, useful to man, are drowned by being overflowed even for a short time, and are injured by any stagnant water about their roots. Why this is so, it is not easy to explain. Most of our knowledge on these points, is derived from observation. We know that fishes live in water, and if we would propagate them, we prepare ponds and streams for the purpose. Our domestic animals live on land, and we do not put them into fish-ponds to pasture. There are useful plants which thrive best in water. Such is the cranberry, notwithstanding all that has been said of its cultivation on upland. And there are domestic fowls, such as ducks and geese, that require pools of water; but we do not hence infer that our hens and chickens would be better for daily immersion. All lands, then, require drainage, that contain too much water, at any season for the intended crops.
This will be found to be an important element in our rule. Land may require drainage for Indian corn, that may not require it for grass. Most of the cultivated grasses are improved in quality, and not lessened in quantity, by the removal of stagnant water in Summer; but there are reasons for drainage for hoed crops, which do not apply to our mowing fields. In New England, we have for a few weeks a perfect race with Nature, to get our seeds into the ground before it is too late. Drained land may be plowed and planted several weeks earlier than land undrained, and this additional time for preparation is of great value to the farmer. Much of this same land would be, by the first of June, by the time the ordinary planting season is past, sufficiently drained by Nature, and a grass crop upon it would be, perhaps, not at all benefitted by thorough-drainage; so that it is often an important consideration with reference to this operation, whether a given portion of our farm may not be most profitably kept in permanent grass, and maintained in fertility by top-dressing, or by occasional plowing and reseeding in Autumn. It is certainly convenient to have all our fields adapted to our usual rotation, and it is for each man to balance for himself this convenience against the cost of drainage in each particular case.
What particular crops are most injured by stagnant water in the soil, or by the too tardy percolation of rain-water, may be determined by observation. How stagnant water injures plants, is not, as has been suggested, easily understood in all its relations. It doubtless retards the decomposition of the substances which supply their nutriment, and it reduces the temperature of the soil. It has been suggested, that it prevents or checks perspiration and introsusception, and it excludes the air which is essential to the vegetation of most plants. Whatever the theory, the fact is acknowledged, that stagnant water in as well as on the soil, impedes the growth of all our valuable crops, and that drainage soon cures the evil, by removing the effect with its cause. And the remedy seems to be almost instantaneous; for, on most upland, it is found that by the removal of stagnant water, the soil is in a single season rendered fit for the growth of cultivated crops. In low meadows, composed of peat and swamp mud, in many cases, exposure to the air for a year or two after drainage, is often found to enhance the fertility of the soil, which contains, frequently, acids which need correction.
INDICATIONS OF TOO MUCH MOISTURE.
It has already been suggested, that motives of convenience may induce us to drain our lands—that we may have a longer season in which to work them; and that there may be cases where the crop would flourish if planted at precisely the right time, where yet we cannot well, without drainage, seasonably prepare for the crop. Generally, however, lands too wet seasonably to plant, will give indications, throughout the season, of hidden water producing its ill effects.
If the land be in grass, we find that aquatic plants, like rushes or water grasses, spring up with the seeds we have sown, and, in a few years, have possession of the field, and we are soon compelled to plow up the sod, and lay it again to grass. If it be in wheat or other grain, we see the field spotted and uneven; here a portion on some slight elevation, tall and dark colored, and healthy; and there a little depression, sparsely covered with a low and sickly growth. An American traveling in England in the growing season, will always be struck with the perfect evenness of the fields of grain upon the well-drained soil. Journeying through a considerable portion of England and Wales with intelligent English farmers, we were struck with their nice perception on this point.
The slightest variation in the color of the wheat in the same or different fields, attracted their instant attention.
"That field is not well-drained; the corn is too light-colored." "There is cold water at the bottom there; the corn cannot grow;" were the constant criticisms, as we passed across the country. Inequalities that, in our more careless cultivation, we should pass by without observation, were at once explained by reference to the condition of the land, as to water.
The drill-sowing of wheat, and the careful weeding it with the horse-hoe and by hand, are additional reasons why the English fields should present a uniform appearance, and why any inequalities should be fairly referable to the condition of the soil.
Upon a crop of Indian corn, the cold water lurking below soon places its unmistakable mark. The blade comes up yellow and feeble. It takes courage in a few days of bright sunshine in June, and tries to look hopeful, but a shower or an east wind again checks it. It had already more trouble than it could bear, and turns pale again. Tropical July and August induce it to throw up a feeble stalk, and to attempt to spindle and silk, like other corn. It goes through all the forms of vegetation, and yields at last a single nubbin for the pig. Indian corn must have land that is dry in Summer, or it cannot repay the labor of cultivation.
Careful attention to the subject will soon teach any farmer what parts of his land are injured by too much water; and having determined that, the next question should be, whether the improvement of it by drainage will justify the cost of the operation.
WILL IT PAY?
Drainage is a permanent investment. It is not an operation like the application of manure, which we should expect to see returned in the form of salable crops in one or two years, or ten at most, nor like the labor applied in cultivating an annual crop. The question is not whether drainage will pay in one or two years, but will it pay in the long run? Will it, when completed, return to the farmer a fair rate of interest for the money expended? Will it be more profitable, on the whole, than an investment in bank or railway shares, or the purchase of Western lands? Or, to put the question in the form in which an English land-owner would put it, will the rent of the land improved by drainage, be permanently increased enough to pay a fair interest on the cost of the improvement?
Let us bring out this idea clearly to the American farmer by a familiar illustration. Your field is worth to you now one hundred dollars an acre. It pays you, in a series of years, through a rotation of planting, sowing, and grass, a nett profit of six dollars an acre, above all expenses of cultivation and care.
Suppose, now, it will cost one-third of a hundred dollars an acre to drain it, and you expend on each three acres one hundred dollars, what must the increase of your crops be, to make this a fair investment? Had you expended the hundred dollars in labor, to produce a crop of cabbages, you ought to get your money all back, with a fair profit, the first year. Had you expended it in guano or other special manures, whose beneficial properties are exhausted in some two or three years, your expenditure should be returned within that period. But the improvement by drainage is permanent; it is done for all time to come. If, therefore, your drained land shall pay you a fair rate of interest on the cost of drainage, it is a good investment. Six per cent. is the most common rate of interest, and if, therefore, each three acres of your drained land shall pay you an increased annual income of six dollars, your money is fairly invested. This is at the rate of two dollars an acre. How much increase of crop will pay this two dollars? In the common rotation of Indian corn, potatoes, oats, wheat, or barley, and grass, two or three bushels of corn, five or six bushels of potatoes, as many bushels of oats, a bushel or two of wheat, two or three bushels of barley, will pay the two dollars. Who, that has been kept back in his Spring's work by the wetness of his land, or has been compelled to re-plant because his seed has rotted in the ground, or has experienced any of the troubles incident to cold wet seasons, will not admit at once, that any land which Nature has not herself thoroughly drained, will, in this view, pay for such improvement?
But far more than this is claimed for drainage. In England, where such operations have been reduced to a system, careful estimates have been made, not only of the cost of drainage, but of the increase of crops by reason of the operation.
In answer to questions proposed by a Board of Commissioners, in 1848, to persons of the highest reputation for knowledge on this point, the increase of crops by drainage was variously stated, but in no case at less than a paying rate. One gentleman says: "A sixth of increase in produce of grain crops may be taken as the very lowest estimate, and, in actual result, it is seldom less than one-fourth. In very many cases, after some following cultivation, the produce is doubled, whilst the expense of working the land is much lessened." Another says: "In many instances, a return of fully 25 per cent. on the expenditure is realized, and in some even more." A third remarks, "My experience and observation have chiefly been in heavy clay soils, where the result of drainage is eminently beneficial, and where I should estimate the increased crop at six to ten bushels (wheat) per statute acre."
These are estimates made upon lands that had already been under cultivation. In addition to such lands as are merely rendered less productive by surplus water, we have, even on our hard New England farms—on side hills, where springs burst out, or at the foot of declivities, where the land is flat, or in runs, which receive the natural drainage of higher lands—many places which are absolutely unfit for cultivation, and worse than useless, because they separate those parts of the farm which can be cultivated. If, of these wet portions, we make by draining, good, warm, arable land, it is not a mere question of per centage or profit; it is simply the question whether the land, when drained, is worth more than the cost of drainage. If it be, how much more satisfactory, and how much more profitable it is, to expend money in thus reclaiming the waste places of our farms, and so uniting the detached fields into a compact, systematic whole, than to follow the natural bent of American minds, and "annex" our neighbor's fields by purchasing.
Any number of instances could be given of the increased value of lands in England by drainage, but they are of little practical value. The facts, that the Government has made large loans in aid of the process, that private drainage companies are executing extensive works all over the kingdom, and that large land-holders are draining at their own cost, are conclusive evidence to any rational mind, that drainage in Great Britain, at least, well repays the cost of the operation.
In another chapter may be found accurate statements of American farmers of their drainage operations, in different States, from which the reader will be able to form a correct opinion, whether draining in this country is likely to prove a profitable operation.
CHAPTER V.
VARIOUS METHODS OF DRAINAGE.
Open Ditches.—Slope of Banks.—Brush Drains.—Ridge and Furrow.—Plug-Draining.—Mole-Draining.—Mole-Plow.—Wedge and Shoulder Drains.—Larch Tubes.—Drains of Fence Rails, and Poles.—Peat Tiles.—Stone Drains Injured by Moles.—Downing's Giraffes.—Illustrations of Various Kinds of Stone Drains.
OPEN DITCHES.
The most obvious mode of getting rid of surface-water is, to cut a ditch on the surface to a lower place, and let it run. So, if the only object were to drain a piece of land merely for a temporary purpose—as, where land is too wet to ditch properly in the first instance, and it is necessary to draw off part of the surplus water before systematic operations are commenced—an open ditch is, perhaps, the cheapest method to be adopted.
Again: where land to be drained is part of a large sloping tract, and water runs down, at certain seasons, in large quantities upon the surface, an open catch-water-ditch may be absolutely necessary. This condition of circumstances is very common in mountainous districts, where the rain which falls on the hills flows down, either on the visible surface or on the rock-formation under the soil, and breaks out at the foot, causing swamps, often high up on the hill-sides. Often, too, in clay districts, where sand or loam two or three feet deep rests on tough clay, we see broad sloping tracts, which form our best grass-fields.
If we are attempting to drain the lower part of such a slope, we shall find that the water from the upper part flows down in large quantities upon us, and an open ditch may be most economical as a header, to cut off the down-flowing water; though, in most cases, a covered drain may be as efficient.
At the outlets, too, of our tile or stone drains, when we come down nearly to the level of the stream which receives our drainage-water, we find it convenient, often, and indeed necessary, to use open ditches—perhaps only a foot or two deep—to carry off the water discharged. These ditches are of great importance, and should be finished with care, because, if they become obstructed, they cause back-water in the drains, and may ruin the whole work.
Open drains are thus essential auxiliaries to the best plans of thorough drainage; and, whatever opinion may be entertained of their economy, many farmers are so situated that they feel obliged to resort to them for the present, or abandon all idea of draining their wet lands. We will, therefore, give some hints as to the best manner of constructing open drains; and then suggest, in the form of objections to them, such considerations as shall lead the proprietor who adopts this mode to consider carefully his plan of operations in the outset, with a view to obviate, as much as possible, the manifest embarrassments occasioned by them.
As to the location of drains in swamps and peculiarly wet places, directions may be found in another chapter. We here propose only to treat of the mode of forming open drains, after their location is fixed.
The worst of all drains is an open ditch, of equal width from top to bottom. It cannot stand a single season, in any climate or soil, without being seriously impaired by the frosts or the heavy rains. All open drains should be sloping; and it is ascertained, by experiment, what is the best, or, as it is sometimes expressed, the natural slope, on different kinds of soil. If earth be tipped from a cart down a bank, and be left exposed to the action of the weather, it will rest, and finally remain, at a regular angle or inclination, varying from 21 deg. to 55 deg. with the horizon, according to the nature of the soil. The natural slope of common earth is found to be about 33 deg. 42'; and this is the inclination usually adopted by railroad engineers for their embankments.
If the banks of the open ditch are thus sloped, they will have the least possible tendency to wash away, or break down by frost.
Again: where open ditches are adopted in mowing fields, they may, if not very deep, be sloped still lower than the natural slope, and seeded down to the bottom; so that no land will be lost, and so that teams may pass across them.
This amounts, in fact, to the old ridge and furrow system, which was almost universal in England before tiles were used, and is sometimes seen practiced in this country. The land, by that system, is back-furrowed in narrow lands, till it is laid up into beds, sloping from the tops, or backs, to the furrows which constitute the drains. This mode of culture is very ancient, and is probably referred to in the language of the Psalmist, in the Scriptures: "Thou waterest the ridges thereof abundantly, thou settlest the furrows thereof, thou makest it soft with showers."
The objections to open ditches, as compared with under-drains, may be briefly stated thus:
1. They are expensive. The excavation of a sloping drain is much greater than that of an upright drain. An open drain must have a width of one or two feet at the bottom, to receive the earth that always must, to some extent, wash into it. An open drain requires to be cleaned out once a year, to keep it in good order. There is a large quantity of earth from an open drain to be disposed of, either by spreading or hauling away. Thus, a drain of this kind is costly at the outset, and requires constant labor and care to preserve it in working condition.
2. They are not permanent. A properly laid underdrain will last half a century or more, but an open drain, especially if deep, has a constant tendency to fill up. Besides, the action of frost and water and vegetation has a continual operation to obstruct open ditches. Rushes and water-grasses spring up luxuriantly in the wet and slimy bottom, and often, in a single season, retard the flow of water, so that it will stand many inches deep where the fall is slight. The slightest accident, as the treading of cattle, the track of a loaded cart, the burrowing of animals, dams up the water and lessens the effect of the drain. Hence, we so often see meadows which have been drained in this way going back, in a few years, into wild grass and rushes.
3. They obstruct good husbandry. In the chapter upon the effects of drainage on the condition of the soil, we suggest, in detail, the hindrances which open ditches present to the convenient cultivation of the land, and, especially, how they obstruct the farmer in his plowing, his mowing, his raking, and the general laying out of his land for convenient culture.
4. They occupy too much land. If a ditch have an upright bank, it is so soft that cattle will not step within several feet of it in plowing, and thus a strip is lost for culture, or must be broken up by hand. If, indeed, we can get the plow near it, there being no land to rest against, the last furrow cannot be turned from the ditch, and if it be turned into it, must be thrown out by hand. If the banks be sloped to the bottom, and the land be thus laid into beds or ridges, the appearance of the field may, indeed, be improved, but there is still a loss of soil; for the soil is all removed from the furrow, which will always produce rushes and water-grass, and carried to the ridge, where it doubles the depth of the natural soil. Thus, instead of a field of uniform condition, as to moisture and temperature and fertility, we have strips of wet, cold, and poor soil, alternating with dry, warm, and rich soil, establishing a sort of gridiron system, neither beautiful, convenient, nor profitable.
5. The manure washes off and is lost. The three or four feet of water which the clouds annually give us in rain and snow, must either go off by evaporation, or by filtration, or run off upon the surface. Under the title of Rain and Evaporation, it will be seen that not much more than half this quantity goes off by evaporation, leaving a vast quantity to pass off through or upon the soil. If lands are ridged up, the manure and finer portions of the soil are, to a great extent, washed away into the open ditches and lost. Of the water which filters downwards, a large portion enters open ditches near the surface, before the fertilizing elements have been strained out; whereas, in covered drains of proper depth, the water is filtered through a mass of soil sufficiently deep to take from it the fertilizing substances, and discharge it, comparatively pure, from the field. In a paper by Prof. Way (11th Jour. Roy. Ag. Soc.), on "The Power of Soils to retain Manure," will be found interesting illustrations of the filtering qualities of different kinds of soil.
In addition to the above reasons for preferring covered drains, it has been asserted by one of the most skillful drainers in the world (Mr. Parkes), "that a proper covered drain of the same depth as an open ditch, will drain a greater breadth of land than the ditch can effect. The sides of the ditch," he says, "become dried and plastered, and covered with vegetation; and even while they are free from vegetation, their absorptive power is inferior to the covered drain." |
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