Popular Science Monthly/Volume 43/May 1893/How Science Is Helping the Farmer




A SCORE or more years ago, when Horace Greeley and Henry Ward Beecher were telling the American public what they knew about farming, there was quite a general tendency on the part of the agricultural class to hold up to ridicule what was termed "scientific farming." Great claims were then made as to the importance of a knowledge of science, so that the farmer might analyze the soil, crops, fertilizers, etc. Especial stress was laid upon having a knowledge of chemistry, in order to be able to analyze something. Chemistry was to be the panacea for all the farmer's ills, and writers indiscriminately quoted Liebig, Boussingault, Johnston, Lawes, and Gilbert, and other famous agricultural chemists. There was much book farming done that was a source of amusement for practical agriculturists. Much of the written matter and advice • published was worthless, and time and the labors of science conclusively demonstrated as much. Early investigators, engaged in faithful and hard work, gleaned much information of scientific importance, and eventually overturned numerous theories that had hitherto seemed plausible. Chief among these was the analysis of soils, whereby one could know the composition of his soil and at once determine in what ingredients of plant food it was deficient, so that he might feed back to it the lacking elements. Time and study have shown that soil is a very complex substance, and one analysis is usually quite unsatisfactory, because a little sample of soil represents only a small piece of ground, perhaps representing quite unfairly the entire field. Consequently, as remarked by Dr. Caldwell,[1] soil analyses are not thoroughly practical, on account of the difficulty in securing a sample of a few pounds that shall correctly represent the millions of pounds of soil in even a single acre, to say nothing of a field of many acres.

Fifty years ago Justus von Liebig, a German chemist, through an interest in rural economy which resulted in far-reaching discoveries, established himself as the father of agricultural chemistry. His investigations largely related to the composition of the soil and plant nutrition. He was the first to prove that plants fed on certain ingredients of the soil, and that different classes of soils and plants varied in their composition. Liebig's was the pioneer work, and from his time to the present a mass of scientific information has been gradually accumulating that in numerous ways is serving a good purpose. Never before in history have scientific workers been so practical as now. We live in essentially a practical age, and men live better, more intelligently, and more easily than ever before. Practical problems engage the attention of the scientist over all others; and so, instead of ridicule, science as applied to the farm is now receiving most respectful consideration, for the work is practical, and sound practice always receives respectful attention.

Science is knowledge. There is no scientific farming. The highest type of farming is intelligent farming. The intelligent farmer of to-day is simply making use of certain scientific facts that have a practical application.

For a half century science has been laboring in the interests of agriculture. This year the United States appropriates nearly one million dollars for scientific experimentation as applied to agriculture. And yet but few farmers realize how material is the assistance being given the agricultural classes of the country through the direct application of accomplished scientific work. In view of this condition of affairs, in the following pages I propose to give illustrations of what is now in practical use, showing how science has helped and is helping the farmer. These examples signify something. They mean a saving of millions of dollars to the people of the country. Millions have been saved to the farmers in the past; millions will be saved in the future; and all through the aid of scientific research.

The first real substantial assistance received by the farming public from science was in the examination and inspection of commercial fertilizers. Liebig demonstrated that plants secured most of their nutrition from soil ingredients. Nitrogen, potash, and phosphoric acid were those most in demand by the plant, and where crops were removed from the soil these articles of plant food were diminished, thereby reducing cropping capacity. Soil exhaustion in a measure followed if these substances were not returned to feed subsequent crops. Natural manures (animal excrement) contained nitrogen, potash, and phosphoric acid; consequently soil fertility could be maintained by the application of these. But chemistry here came to the farmer's aid, by suggesting that the various essentials of plant food be supplied in artificially prepared form. Nitrogen could be obtained from Peruvian guano and animal matter, potash from wood ashes or German salts, and phosphoric acid from bones; consequently these substances could be supplied as desired. With the propagation of this idea was developed the commercial fertilizer, and artificial manures were made and sold on the market as is any other commodity. However, it was not long before much fraudulent material found its way into the buyer's hands; many dealers were not honest, and farmers were often outrageously swindled. Here, again, the chemists came to the assistance of agriculture. Fertilizers could be analyzed, their component parts determined, and purchasers might learn how many pounds of plant food a ton of artificial manure contained. Nitrogen, potash, and phosphoric acid each had a commercial value per pound; consequently the chemist could easily determine in a fair manner the value of a ton of fertilizer.

In 1872, through the efforts of Dr. C. A. Goessmann, Professor of Chemistry in the Massachusetts Agricultural College, the Massachusetts Legislature passed a law appointing a State inspector of fertilizers, requiring that all fertilizer manufacturers making a fertilizer having a valuation of over twelve dollars a ton should print on a tag attached to the bag or barrel containing the same the percentage of nitrogen, potash, and phosphoric acid in the brand sold. Samples of all fertilizers selling for over twelve dollars per ton had first to be analyzed by the State chemist before they could be sold in the market; and this officer, designated "inspector," was authorized to sample and analyze any or all fertilizers sold in the State. This Massachusetts law was at first more or less imperfect, but it was later on amended and made eminently satisfactory to both the manufacturer and the consumer. Other States followed the example of Massachusetts, and to-day there is not a State in the Union handling fertilizers to any extent that has not upon its statute-books laws patterned to some degree after the Massachusetts idea, and as a result manufacturers can not with safety sell the farmers shoddy fertilizers. Now and then a fraudulent fertilizer appears, but its sale is quickly stopped by the chemist's exposure. Only a short time ago (the summer of 1890) two fertilizers were suddenly placed upon the Indiana market and sold for $27.50 and $22.50 per ton, respectively. These were analyzed by the State chemist, and the former was found to have a value of $5.76 and the latter of $4.44 per ton. These were out-and-out swindles; yet, had it not been for a prompt publication from the State Experiment Station at Purdue University as to their real character, many farmers of the State of Indiana would have been unmercifully swindled. In view of the fact that millions of dollars' worth of fertilizers are sold yearly in the United States, one can readily understand how great is the sum of money that is being yearly saved to the farmers of the country through the interposition of the chemist.

In the Eastern and more populous part of the United States, which has been long under cultivation, farm manures are more highly valued than in the newer regions of the country. For years investigators have advised that stable manure be handled economically. Chemists argued that, unless properly protected, these manures would lose much of their valuable properties, mainly through rain leaching away the soluble plant food. Figures supplied from foreign investigation were used to prove the point. Finally, in 1889 the Cornell University Agricultural Experiment Station did some practical work to demonstrate how farmyard manure would deteriorate by leaching and fermentation.[2] It was shown that one ton of fresh horse manure had a valuation of $2.45, but exposed outdoors for six months its valuation was $1.42, a loss of 81.03 per ton, or forty-two per cent. Mixed horse and cow manure, after leaching for six months, showed a loss of 9·2 per cent, a less amount, no doubt, than occurs on the average farm.

At the present time, while there is a vast loss of plant food to the farms through the improper care of the manure produced thereon, there is at the same time saved to economic use an enormous amount of fertility through the careful husbanding of the materials as produced upon the farms of those who are intelligent and economical. We must give scientific investigation the credit for thus showing husbandmen how important farm losses may be prevented; the numerous devices at present used on the farm for conserving manures, such as manure sheds, pits, cellars, etc., are money-saving equipments.

In a somewhat different direction, yet in a line where the work of the chemist is of equal if not greater importance than in fertilizer control, is the inspection of milk. Milk is the most essential article of food for human consumption, for, properly used, it is as nearly a perfect food as is known. But milk is a fluid, and as such is easily adulterated. It consists of from eighty-five to eighty-eight per cent water, and twelve to fifteen per cent solid substance—as fat, casein (cheesy matter), albumen, sugar, and ash. On the percentage and purity of solids in milk is its quality mainly dependent. After the selling of milk became a recognized industry, adulteration came more or less to be practiced. The pump was brought into requisition. Flour, chalk, and other ingredients were used to thicken it. In 1872 Dr. C. F. Chandler, of Columbia College, stated[3] that, from long-continued investigation, the milk supply of New York and Boston receives on an average one quart of water to every three quarts of pure milk before reaching consumers. He further says, "With the addition of water in the proportion of one to three before delivering to consumers, we find milk-growers deprived of a business which would return to them 81,390,000 yearly, at an average first price of fifteen cents per gallon, city consumers, on the other hand, paying more than $3,700,000 annually for water."

Here the dairy farmer was either injuring his own interests or some other fellow was hurting it. The intelligent producer realizes that anything that is done to injure the character of market milk injures the general trade. Were pure milk always placed on the market, a better price could be secured for it, and there would not be the extensive sale for patent baby foods and condensed milk that there now is. To remedy this evil it became necessary to treat milk in a measure as the fertilizers were treated, or, in other words, determine the character of milk by analysis. As in fertilizer control, so in milk inspection, Massachusetts was a pioneer worker. The first act to punish fraud in the sale of adulterated milk in Massachusetts was passed by the Legislature in 1856. This law was ineffective, so in 1859 a new law was enacted, which provided for the appointment of milk inspectors in towns and cities, whose duties it should be to detect adulteration of milk, and secure the conviction and punishment of offenders. This law has since been frequently amended and improved. At the present time the Massachusetts law requires all milk to contain at least thirteen per cent solids, and milk containing less than that amount is condemned. Since the Massachusetts law was first enacted the more progressive dairy States of the Union have passed laws to prevent deception in the sale of dairy products, and usually twelve per cent of solids is required in the milk sold in the market. The London (England) milk supply is carefully watched by inspectors. The Aylesbury Dairy Company of London is the largest of its kind in the world. During 1891 chemists analyzed 21,855 samples of the milk of this company, and found before delivery 12·75, during delivery 12·74, and after delivery 12·81 per cent solids, showing a very good grade of milk.[4]

That substance which makes milk most palatable is the fat in it. Good milk should have four or five; cream, eighteen to twenty-five, and butter, eighty to eighty-five per cent of fat. Skim milk, or thin, insipid, disagreeable milk, contains a small amount of milk fat. When we speak of rich milk, we mean that which contains a large percentage of this substance. There are in the United States many thousands of cows, each of which does not produce over one fourth or one half the amount of butter it should. The claim is made[5] that the average yield of our dairy cows is not over one hundred and twenty-five pounds of butter a year, whereas it should be three hundred pounds at the least. Some cows produce a much larger percentage of fat or butter in their milk than do others. The farmer should own the better class of the two, the butter dairyman can only afford to keep profitable cows, and the thousands of creameries over the country can not afford to purchase good and poor milk for one and the same price, for that is unjust to the person supplying the best grade of milk. Consequently, for some years chemists have been laboring to invent some simple method of determining the percentage of fat in milk, so that creamery men and farmers with a common education might be able to use it, and thus test their milk accurately. The first method for practical application among farmers to attract very general attention was that devised by Mr. F. G. Short, chemist to the Wisconsin Experiment Station, whose method was published in 1888.[6] This, however, was somewhat complex, and too slow of operation. Other methods were afterward developed by Messrs. Patrick, Parsons, Cochran, Babcock, etc. Dr. S. M. Babcock, while chemist at the New York State Experiment Station, did much valuable work in the study of milk and its products, and in 1889, after becoming chemist of the State Experiment Station at Madison, Wis., he developed and brought out a method for testing the fat in milk or cream that is now a recognized success. The method is simple, and can easily be performed by any person of fair intelligence. Equal quantities of milk and sulphuric acid are placed in specially constructed bottles, and these put in a simple machine, largely consisting of a tin cylinder or wheel, about fifteen or twenty inches in diameter, revolving on its side, within which, after the manner of spokes, are cups or pockets, in which these bottles are placed. The wheel is revolved by a crank and cog movement, and by centrifugal force and the action of the acid the fat in the milk is separated from the rest of the fluid. Enough hot water is added to each bottle to fill the measuring neck, and the fat, after five or six minutes' turning of the machine, comes to the top clear and yellow, after which the amount present may be read upon the graduated lines on the sides of the long neck of the bottle. The milk of as many as twenty-four cows can be tested in an hour. Machines of from four to fifty bottles capacity are manufactured.

This invention, the result of long and laborious scientific research, is not patented, and is largely used in the creameries of Wisconsin, Iowa, Illinois, and many other States in the purchasing of milk. The patrons of the creameries are paid for their milk according to its quality, as decided by the Babcock machine. Such a method as this is a blessing to the country, for it informs the farmer if his milk is inferior to that of his neighbor, and will consequently incite him to improve his stock. The Babcock milk-testing machine is now just as generally sold by dairy firms as is an improved churn or butter-worker.

One of the most wonderful of agricultural inventions is the centrifugal or milk separator. Briefly, this machine is designed to separate the cream from the milk as soon as drawn from the cow, thus dispensing with the old process of setting milk and waiting for the cream to rise by gravity. At the International Dairy Show at Hamburg, in 1877, an instrument was exhibited[7] consisting of two wheels in a stand, one of which actuated the other by means of a belt. In the upper wheel four glass tubes containing milk were securely placed, and the lower wheel was then revolved, giving the upper upward of one thousand revolutions per minute. Whirling at this speed brought centrifugal force to bear on the milk in the tubes, and the cream, being lightest, collected at one end and the skim milk at the other.[8]

In 1879 De Laval, a Swede, exhibited to the British public at Kilburn a centrifugal separator entirely unlike the preceding one, and this machine of De Laval, in principle and general plan, is the form now commonly used over Europe and America. Milk, warm from the cow, is conveyed into a hollow steel drum about ten inches in diameter, which is made to revolve six thousand to seven thousand times per minute within a slightly larger metal chamber. The skim milk, being heavier, is thrown to the outside, and passes off through a tube which rises from a point in the skim milk where the least amount of fat exists to the upper edge of the drum; while the lighter cream rises near the center of the drum and passes off through another hole, coming out of the separator on the opposite side from the skim milk. One or two thousand pounds of milk an hour may be creamed with this machine, when run by horse or steam power. Several other designs of centrifugals have more recently been invented, some of greater capacity than the De Laval, but at the present day the modern De Laval's is unsurpassed. For small dairies De Laval invented a hand separator, which is known as "the baby separator." With the No. 2 size one person can separate the cream from three hundred pounds of milk in an hour, the drum making six thousand revolutions per minute to forty-two turns of the crank.

The manufacture of this cream separator has been followed by the invention and introduction within the past two years of a combined cream separator and butter extractor, which makes it practicable to run milk into the machine and take from it butter, thus avoiding the handling of the cream at all.

The cream separator enables the dairyman to dispense with numerous utensils ordinarily used in setting milk, and in hot climates is invaluable, as it saves much of the great expense of ice. Centrifugal cream is unexcelled. In a comparatively few years these valuable dairy utensils will be commonly found in use on the dairy farms of the country.

Never before in the history of man have agricultural plants apparently suffered so greatly from parasitic vegetable growths and injurious insects. The conditions of growth have been made so much more intense for many plants that they have in consequence, in certain directions, thus made themselves more vulnerable to the attacks of parasites and insects. Some insects have been deprived of their normal food in a large degree, and have sought sustenance in agricultural crops. The destruction of these ravagers meant the saving of valuable crops; consequently much important experimental work has been accomplished with fungicides and insecticides.

For two score of years the grape rot has caused immense damage in the vineyards of the Eastern United States. A small plant, so minute as to require a high-power microscope to bring it to view, feeds upon the juices of the tender leaves and berries of the grape, blasting and ruining the fruit. The parasite matures and ripens its spores or seeds in vast quantities, and these are blown over adjacent vines and the disease more widely scattered.

Within a few years the botanists of both Europe and America began to devise means to prevent this malady. After long experimental work with fungicides and spraying machines, a mixture of sulphate of copper (six pounds), unslaked lime (four pounds), and water (forty-five gallons), termed Bordeaux mixture, was adopted,[9] which, when sprayed on the vines several times during the growing season before the grapes became ripe, completely prevented the ravages of the rot. Applications are made after the buds have started, and four or five times later on. Experiments, generally conducted by scientists with the Bordeaux mixture, have shown it to be most excellent for preventing numerous diseases of plants caused by parasitic growth. The method is cheap, and small hand machines, or large pump tanks with spraying attachments and drawn by teams, are made, by which one can rapidly and effectively spray large areas at comparatively slight expense. So extensive is the use of Bordeaux mixture becoming that all along the Hudson and in other grape regions, in vineyards of the country, this is the method employed to save the crop from black rot, mildew, etc.

In the cereal-growing regions, oats and wheat are frequently damaged by the ravages of smut, a disease nearly all farmers are familiar with, which destroys the seed or the entire head. This smut is a mass of spores or seeds of a parasitic plant ripened in the seed grain. The spores are scattered over the field, and mingle among the grain when thrashed out. The grain is planted in the fall or spring, and the spores of the parasite germinate and grow along with the young plant, feeding on its juices. When the head of the plant begins to mature its seed it is blasted by the smut.

A simple remedy has been devised to combat the smut of oats and what is known as "bunt" or stinking smut of wheat. Investigations begun by Prof. Jensen, a Danish scientist, and also conducted at the Kansas and Purdue University Experiment Stations, conclusively show that by soaking the seeds of these cereals in water at a temperature of 135° to 140° Fahr. for five minutes all the spores were killed, and the crop from the treated seed would grow free of the malady. This simple method, costing nothing for materials, bids fair to be extensively used in future. It is estimated, as a result of investigation, that ten per cent of the oat crop is destroyed by smut. In 1889 the oat crop of Indiana amounted to 28,710,935 bushels. The value of the estimated ten per cent of loss is $797,520 for 3,190,104 bushels of oats at 25 cents a bushel. Certainly, if this sum can be saved it should be.

Few people realize the enormous loss to agriculture through the ravages of insects. In his annual address before the Association of Economic Entomologists at Washington in August, 1891, Mr. James Fletcher, the president, gave important facts concerning the extent of the losses from insect ravages. In 1864, Dr. Shimer estimated the loss to the corn and grain crops of Illinois to be $73,000,000. In 1874, Dr. Riley estimated a loss to Missouri by insects of 819,000,000. In 1887, Prof. Osborne, of the Iowa Agricultural College, estimated the loss to Iowa by insects at $25,000,000. Mr. L. O. Howard, in 1887, estimates $00,000,000 losses from chinch bug in nine States; and Prof. Comstock estimates that the cotton Aletia in 1879 caused a loss of $30,000,000 in the cotton States. Finally, Mr. Fletcher estimates $380,000,000 as the sum total per year for losses from insect ravages.

There are numerous illustrations available to demonstrate how great are the services of scientific research, from an entomological point of view, to agriculture, but I will refer to only three, as these are of striking interest and serve to illustrate the work.

The citrus industry of California is a great one, involving hundreds of thousands of dollars. What is known as the fluted scale insect had for about twenty-five years a foothold in the orange and lemon groves, and bade fair to cause enormous losses to the orchardists. A study was made of the parasites affecting this scale insect, and in 1888 the United States Government sent two entomologists to Australia to study the parasites of the scale insects in that country, and bring live specimens to California to distribute in the orange and lemon groves. Suffice it to say that these parasites rapidly multiplied and fed upon both the white and fluted scale, to their destruction. With surprising rapidity the beneficial insect destroyed the injurious one. Says Dr. C. V. Riley, United States Entomologist,[10] "The history of the introduction of this pest (scale insect), its spread for upward of twenty years, and the discouragement which resulted, the numerous experiments which were made to overcome the insect, and its final reduction to unimportant numbers by means of an apparently insignificant little beetle imported for the purpose from Australia, will always remain one of the most interesting stories in the records of practical entomology."

I have just quoted Mr. Howard's statement that the chinch bug in 1887 caused $60,000,000 of losses in nine States. A few years ago the attention of entomologists was drawn to the fact that chinch bugs occasionally died in large numbers from a peculiar disease. The bugs were found on the ground dead and covered with a white fungus. This disease seemed to be infectious, and several entomologists gave special attention to the matter. Prof. F. H. Snow, of the University of Kansas, pushed the investigation and thought it possible to artificially induce the disease and communicate it to healthy bugs, and thus diminish their numbers, and for the past three years Prof. Snow has worked upon this line. The Legislature of Kansas appropriated $3,500 for carrying on his investigations during 1891-'92.

In his annual report to the Governor of Kansas, describing his investigations. Prof. Snow gives a list of 1,400 persons who conducted experiments under his direction in 1891, to assist in disseminating the disease. Of these 1,071 were successful, 181 unsuccessful, and 148 doubtful, in their attempts. As a result of their season's work. Prof. Snow estimates that, on the basis of the reports rendered, 8200,000 in crops were saved to those 1,071 persons who worked under his instruction.[11] Four hundred and eighty-two farmers reported to him an estimated saving of 887,244.10 through scattering the diseased insects among the healthy, thus resulting in the rapid destruction of all. While this is experimental work, and may not invariably give the satisfactory results to be wished for, it illustrates in a striking manner one way in which science is working in the interests of agriculture.

In 1887 what is known as the gypsy moth (Ocneria dispar) was discovered in eastern Massachusetts. This insect was originally brought to Massachusetts from France, where it is exceedingly destructive to vegetation, and especially the foliage of trees. When first found in Massachusetts its character was not known by the finder, but when later examined by Prof. Fernald, of the State Agricultural College, he, knowing its nature, at once began an investigation to ascertain how much of a foothold it had in the State. It was located in numerous towns. The Legislature was advised of the dangerous character of the insect. A State law was enacted to provide against the depredations of the gypsy moth. Several commissioners were appointed and money appropriated to eradicate the insect. During the entire growing season of 1892 bands of men were engaged in destroying this insect in its various forms, and every effort is being made to prevent its further increase.

Perhaps the most serviceable labor given by science to the cultivator, in its application to insects, is the invention and perfection of insecticides. A great number of experiments have been conducted in agricultural colleges and experiment stations over the country with solutions and powders with which to kill injurious insects. Arsenic in different preparations, carbolized plaster, kerosene, hellebore, pyrethrum, hot water, and Bordeaux mixture have been in use and tested in many ways, so that, as a result of this work, standard insecticides can be recommended to farmers generally, which may be easily made at home out of simple ingredients. What is termed the kerosene emulsion is perhaps, all things considered, the best general insecticide in use. This may be made as follows, following Cook's directions:[12] Dissolve in two quarts of water one quart of soft soap or one fourth pound of hard soap, by heating to boiling; then add one pint of kerosene oil, and stir violently for from three to five minutes. This can then be diluted with twice its bulk of water for use. This emulsion will destroy lice on both live stock and plants.

Finally, we have in the United States nearly fifty experiment stations where trained men are working in the interests of agriculture—men whose one aim is to conduct research of benefit to mankind. Considering this fact, and that numerous scientists outside of the stations are also engaged in a class of work that of necessity is of value to agriculture, farmers should feel satisfied that their interests are being well looked after outside the pale of politics. It requires no effort to emphatically show that already many, many millions of dollars have been gained to agriculture through the disinterested efforts of scientists. Scientific investigation will continue in the future as it has in the past, and it is fair to assume that each year will see much good work done. Certainly no other class of labor is receiving greater benefits from science than is agriculture at the present day.

  1. Agricultural Science, vol. i, p. 25.
  2. Cornell University Agricultural Experiment Station, Bulletin 13, December, 1889.
  3. Report of the Commissioner of Agriculture for 1872, p. 335.
  4. Milch Zeitung, xxi, Nos. 11 and 12.
  5. The Dairy Industry, by Peter Collier, New York, 1889, p. 8.
  6. University of Wisconsin Agricultural Experiment Station, Bulletin No. 16, July, 1888. A New Method for determining Fat in Milk.
  7. Sheldon, Dairy Farming, p. 303.
  8. An editorial in Farm and Fireside, for June 1, 1892, states that the cream separator has been in process of evolution for thirty-three years, and that the first known application of centrifugal force for creaming milk was made in 1859. Dairy authorities, so far as I can learn, give no data on the subject preceding that quoted above in the text.—C. S. P.
  9. American Gardening, April, 1892, p. 260.
  10. United States Department of Agriculture Report, 1889, pp. 334, 335.
  11. University of Kansas Experiment Station, First Annual Report of the Director, for the Year 1891, p. 171.
  12. Michigan Agricultural Experiment Station, Bulletin 76, October, 1891, p. 5. Kerosene emulsion.