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Une
SCIENCE IN FARMING.
A TEXT BOOK
—ON THE—
Principles of ssriculture,
INCLUDING A TREATISE ON
AGRICULTURAL CHEMISTRY.
DESIGNED FOR USE IN
SCHOOLS, GRANGES, FARMERS’ CLUBS, AND BY FARMERS AND THEIR FAMILIES. ¥
By R. 5. THOMPSON. ge
PUBLISHED BY THE FARMERS’ ADVANCE, SPRINGFIELD, OHIO. 1882,
= Ouescbodeseetsee = ¢
~ COPYRIGHT, 1882, BY R. 8S, THOMPSON. _
Success in Farming,
A Series of Practical Talks with Farmers, PA WALDO F. BROWN,
One of the Most Popular Agricultural Writers in the United States.
Handsomely Printed on Heavy Tinted Paper and Elegantly Bound in Cloth.
The Book is Well Arranged and Systematized, and Full of Practical Common Sense.
PRICE, by Mail, Postpaid, - - - + ONE DOLLAR.
Published by “ The Farmers’ Advance,” Springfield, 0.
Its twenty-one chapters consider: What constitutes success in farming ? selection of farm, management, buildings, fences, draining, fertilizing, hired help, implements, wheat, corn , gTasses, clover, potatos, rye, special crops, fruit, garden, stock, poultry, timber, and country homes.
WHAT IS SAID OF SUCCESS IN FARMING. Two Chapters Worth More than the Price of the Kook. I have received Success In Farmrina, and I have received from two chapters—‘‘ Farm Building ”’ and ‘‘ Hired Help ”’—-
benefit worth far more than the price of the book. Frankfort, Ohio. A. B. CLINE,
Every Farmer Ought to Have It.
I have read SUCCESS IN FARMING, and every farmer ought to have it. It surpasses my most sanguine expectations. ‘There is no theory about it. It is all Facts. A child can under- stand it. It only needs to be read to be appreciated.
Bacon P. O., Ohio. JOSEPH LOVE.
TO ALL WHO LABOR TO ADVANCE THE WELFARE, AND INCREASE THE INTELLIGENCE AND HAPPINESS OF MANKIND, THIS BOOK IS DEDICATED.
INTRODUCTION.
The preparation of this book was suggested by the number of inquiries I have received, both personally and by letter, for a book treating on the elements of agriculture.
Careful examination of all the books on the subject I could find, satisfied me that although many of them were excellent, none exactly met the needs of my questioners.
Some of the books on the subject have been pub- lished many years, and, as many of the most impor- tant investigations in this direction have been made — in the past few years, these books are out of date.
Some books of this class were well adapted for the student who was acquainted with the elements of chemistry and physiology, but could not be under- stood by those who had no knowledge of these sciences. Other books were so large and expensive that they exceeded the limits of the average farmer’s time and purse. ;
In others the attempt has been made to condense the subject into such small space, that it had been impossible to treat it in aclear or satisfactory manner.
The great difficulty in the production of such books has been the fact that the men who have fitted them- selves for their preparation, by lives spent in scientific
al SCIENCE IN FARMING.
research, have, by the necessities of the case, been so separated from the great body of the farmers of the country, that it was impossible for them to understand their needs.
The only special fitness that I claim for the prepa- ration of a work of this character, is an intimate acquaintance with the farmers of our country, a strong attachment to the occupation of agriculture, and an earnest desire to see it lifted to its proper place as one of the most honorable, pleasant, and intellectual occupations that can be followed by man.
It is not the design of this book to lay down rules concerning the amount of manure to apply to an acre —nor the exact depth to which grain should be planted, nor the number of pounds of hay that should be fed to acow. These are things which constantly vary with locality, season and circumstance, and which each farmer must, to a certain extent, determine for him- self.
This book teaches the laws and principles that underly the practieal work of the farm, a knowledge of which will enable a farmer to intelligently construct his own rules.
I have not attempted to write a book that can be read merely for entertainment, without mental effort —as a novel, or a fairy tale. It would not be possible to write such a book and convey the information de- sired. There is no “primrose path to learning.”
The important scientific knowledge that is now proving of such great value to the farmer was all ob- tained by patient toil. They who would get the benefit of this knowledge must be willing to give for its ac- quirement at least a moderate amount of mental labor.
INTRODUCTION. Vil
I have earnestly endeavored to make every portion of the work so clear that it can be understood by any who are willing to expend as great amount of mental effort as is needed in the acquirements of other studies. Greater simplicity than this can only be obtained by the sacrifice of value.
Each chapter in this book prepares the way for that which follows, and it would be as unwise to expect to understand the latter chapters before mastering those which precede it,—as it would be to expect a schoolboy to work a sum by the rule of three, before he understood the multiplication table.
I have not attempted to avoid the use of scientific names and terms, my object has been to enable the student to understand not only this book, but the writings of others. I have therefore first explained the meaning of scientific terms and then made _ use of them.
The book is not one of mere theory. It gives the results of long continued and careful experiments made by the most competent men in the world.
No attempt has been made to explain the methods by which the facts given have been ascertained, nor space used in aruguments to prove that they are facts. The aim has been to give the facts themselves, leav- ing the explanation of the methods by which they have been ascertained for books intended for scientific men.
It may be that some readers who have had the ad- vantages of a liberal education, may consider the book too simple, and that too much pains have been taken to explain that which can be understood without ex- planation.
I would ask such to remember that this book is
Vill SCIENCE IN FARMING.
designed for men, many of whom have not had the opportunities for the higher education that is given to the young people of to-day.
It is a book intended to be studied—by the farmer and his family around the fireside, in the district school, in the grange hall, and farmers’ club:
If, by its study, some are enabled to see more of the es and understand more of the mysteries con- nected ae science in farming, and inspired to greater zeal in their efforts to lift the occupation of agriculture to the honored place which is of right its own, I shall fee] repaid for the days and nights of labor that have been expended in its preparation. R182 'B
CONTENTS.
CHAPTER I.
SCIENCE IN FARMING .
CHAPTER II. SCIENCE IN ITS ELEMENTS.
. Terms Used . . The Foundation of Science. . Arithmetic
CHAPTER III.
SCIENCE IN HEAT AND ENERGY. . Their Nature
. Transference of Heat .
. Practical Application
CHAPTER IV. CHEMISTRY.
. Its Nature and Language
. Chemical Laws : ;
. Chemical Symbols and Formula. . The Elements .
. The Compounds .
. Compounds of Acids and Bases . Organic Chemistry
. Combustion and Decay .
PAGE
13
17 19 20
23 25 27
30 33 36 37 41 47 51 58
SCIENCE IN FARMING.
CHAPTER V.
SCIENCE IN AIR.
§ 1. Its Composition and Characteristics
§ 2. §3.
Importance of Each Constituent Summary
CHAPTER VI.
SCIENCE IN SOILS. Origin of Soils . : ; a Uae
. Composition and Classification of Soils © . Properties of Soils
Chemical Characteristics of Soils
- Mechanical Conditions of Soils . Value of Sand, Clay and Humus . Practical Application
CHAPTER VII.
SCIENCE IN PLANT GROWTH. . Composition of Plants .
. Germination
. How the Plant Grows .
. Formation of Seed ‘
. Summary and Practical Application .
CHAPER VIII.
SCIENCE IN ANIMAL LIFE.
. Composition of the Animal . Animal Nutrition .
. Uses of Food in the Body . Disposition Made of Food . Effect of Insufficient Food Z . Effects of Exercise and Exposure to Cold .
af Tae
PAGE,
101
104 105 107 108 110
INDEX.
CHAPTER IX.
SCIENCE IN FOODS. § 1. Food Constituents § 2. Composition of Foods . § 3. Digestibility of Foods § 4. Valuation of Foods §5. Albuminoid Ratio
CHAPTER X.
SCIENCE IN FEEDING.
§ 1. General Principles : § 2. Proper Food for Young Animals § 3. Proper Food for Producing Milk § 4. The Fattening Animal .
§5. The Working Animal
§ 6. Summary
CHAPTER XI.
SCIENCE IN FERTILIZERS.
1, General Principles .
2. Rendering Plant Food pea er 3. Manures 5
4, Farm-Yard Manure
5. Manure from Different Animals
. Relation of Food to Manure
7. Valuation of Manure
8. Commercial Fertilizers
OH sem or)
10. Summary
9. Adaptation of Manures to Crops.
re on
PAGE.
113 114 118 121 124
AUTHOR’S ACKNOWLEDGMENTS.
Had the writer paused at every step of his progress to explain the sources whence his information had been obtained, as much space would have been occu- pied in acknowledgments as in statement of facts, and the design of the work—as a condensed text-book of information—would have been defeated.
In addition to the standard text-books of science, special acknowledgments are due to those two valua- ble works of Johnson’s, How Crops Grow and How Crops FEED; also to Harris’ TaLKs on MANuRES, and to Warrington’s CHEMISTRY OF THE FARM—a book that contains a great amount of valuable information in small space.
Acknowledgments are also due to friends who have kindly aided the work with good words and valuable suggestions all the way, among whom should be named W. I. CHamBeERuain, Secretary of the Ohio State Board of Agriculture, Professor N. W. Lorn, analytical chemist of the Ohio State University, L. N. Bonuaw, agricultural editor of the Cincinnati Com- mercial, W aLpo F. Brown, author ot SuccEss In FARM- Ine, J. W. OaDEN, and others.
CHAPTER I. SCIENCE IN FARMING.
1. Definition of Science.—Webster defines science as “ Truth ascertained”—“ that which is known”— “knowledge duly arranged.”
According to this definition, facts ascertained and duly arranged constitute science, and study of science consists in studying established facts, their arrange- ment and mutual relationship. A mere compilation of facts, without arrangement and without regard to the relations existing between those facts, is not science.
2. Science and Practice.——A distinction is often made between scientific and practical knowledge. Strictly speaking, all scientific knowledge is practical, as it is a knowledge of facts, and practical knowledge becomes scientific when duly arranged.
3. Scientific knowledge isthe result of careful ex- periments conducted with an intelligent purpose.
4. Incommon language, practical knowledge is the knowledge of a fact, and scientific knowledge the knowledge of the principles and causes on which that fact depends.
5. Illustration. — A farmer learns by experience that the manure produced by cattle fed on clover hay
14 SCIENCE IN FARMING.
is more valuable than that produced by cattle fed on straw. This is practical knowledge. Afterwards he learns that this difference is due to the fact that clover contains a larger amount of a substance called nitro- gen, than straw, and that this nitrogen is valuable as amanure. This is scientific knowledge, and this en- ables him to know that manure produced by cattle fed on any other substance containing much nitro- gen will also be of special value, and he can consider this fact in making his selection of foods.
6. The Farmer a Manufacturer——The business of the farmer is to produce certain articles such as wool, cotton, beef, pork, butter, cheese, etc. These can only be produced by bringing together other sub- stances already in existence, and by combination and re-arrangement changing them into the substances de- sired. The farmer is therefore as truly a manufac- turer as the man who makes plows or sewing ma- chines.
7. The soil and air are the sources from which the farmer draws his supplies of raw material, and the plant and animal are the machines by which he works up this raw material into useful manufactured pro- ducts.
8. If the farmer would be successful, he must therefore have a knowledge concerning the substances from which his manufactured goods are to be pro- duced, and of the sources from which he is to obtain them. He also needs to be well acquainted with the machinery he is using, and with the laws that govern | its working. This knowledge isthe“ science of farm- ine”
9. In the earlier days, when the virgin soil was ready to produce a crop if the opportunity were pro-
SCIENCE IN FARMING. 15
vided—when the customs of life were simple, and the farmer’s needs were few, it was possible for men to obtain a living from the soil though they knew but little of the “science of farming.” But with the change in the condition of our soil, the customs of so- ciety, and in the manner of life upon the farm—it has become necessary that a better knowledge of this science should be diffused among the people, and the day is rapidly drawing near when none can hope for success in farming without a knowledge of science in farming.
10. Chemistry—An acquaintance with the ele- ments of chemistry is the key which opens the door to the mysteries of agriculture—for the growth of the plant and the life of the animal are the result of op- erations controlled by chemical laws.
As well might the child expect to read without learning his letters, or the musician to understand music without learning the notes, as the farmer to™understand his occupation without having first learned the elements of chemistry. Letters are not reading; notes are not music, and chemistry is not farming; but as the child cannot read without a knowledge of his letters, neither can the farmer un- derstand the science of his occupation without a knowledge of the elements of chemistry.
11. Agricultural Chemistry. — Strictly speaking, there is no such science. Chemistry and its laws are the same, whether applied to the arts, to manufac- tures or the farm, and the thorough student must learn these laws and Beanie without expecting to see an immediate application.
12. But although a certain knowledge of the laws and principles of chemistry is an essential preparation
16 SCIENCE IN FARMING.
for the study of agriculture, there is much of the de- tails of this science which may, without detriment, be omitted.
In the treatise on chemistry contained in this work, only that is given which is of importance to the farmer.
All that is given should be studied and understood, for it is the key, not to this book alone, but to the books and writings of scientific men.
18. The complaint is often made that the writings of scientific men are beyond the comprehension of the people. The reason is that people have not stud- ied the elementary principles of science.
14. Therefore these elements of science are of the utmost importance. They are not only important in themselves, and full of beauty and interest, but they also prepare the way for wider, deeper, and more in- teresting researches. ;
CLLAI-EER “ET. SCIENCE IN ITS ELEMENTS.
S 1. Terms Used.
In order to understand scientific facts we must first know something of the terms used by scientific men.
15. Matter —Everything that has weight or bulk. Thus, iron is matter, and so is wood, or gold or air. Different parts of matter are called bodies or sub- stances. Matter can change its form—a solid may become a liquid or a gas, and a gas may become a liquid or a solid—or one substance may enter into combination with another, and both lose their former characteristics and gain new ones. But in all these changes matter is neither created nor destroyed. <A house is built by bringing and fastening together wood and iron and stone and brick and mortar, but the house was built, not created—there was no more stone and brick and wood and iron in existence after the house was built than before. So when a plant or animal grows, different substances are gathered to- gether and combined to form the plant or animal; but nothing is created. There are no more of these sub- stances in existence than before. Matter has only changed its form.
16. If a house is torn down, and the material of
which it was built scattered, the bricks and wood 2
18 SCIENCE IN FARMING.
and stone and iron are still in existence. So if, after the plant is grown we put it on the fire and burn it, the matter in the plant changes its form, but is not destroyed. If we should carefully collect the ashes and smoke and vapor and gas produced by burning the plant, we would find they weighed the same as the plant before it was burned. It is impos- sible to create the smallest particle of matter, and equally impossible to destroy it.
17. Solids, Liquids, Gases——Matter exists in three forms. A solid is a substance the particles of which are firmly held together so that they will not move upon each other. Iron is a solid. Liquids are sub- stances in which the particles readily move upon each other and which yet have some attraction for each other. Water is a liquid. A gas is a substance in which the particles seem to have no attraction for each other. The air we breathe is a gas, or rather a mix- ture of gases. :
18. Atoms.—It is supposed that all substances are composed of exceedingly small particles, so small that no microscope has ever been able to reveal them to the eye, and which are called atoms. Between these atoms there exists a force that draws them to- gether, and another that tends to separate them. One is called the attractive, the other the repulsive force. When the attractive force is the strongest, matter exists in the form of a solid. When the two are about equal, in the form of a liquid; and when the repulsive force entirely overcomes the attractive, the substance is called a gas.
19. Force is whatever acts on matter to change it. Thus the force of heat can change a piece of ice into water. Chemical force may cause two substances
SCIENCE IN ITS ELEMENTS. 19
to combine, producing a different one. The force of eravity will cause a substance when not supported to fall to the ground. Like matter, force can neither be created nor destroyed. This will be further explained in the chapter on Heat and Energy.
20. Properties of Matter.— Those characteristics which serve to distinguish one kind of matter from another. Thus it is a property of flint to be hard, of wax to be soft, of snow to be white, of charcoal to be black.
21. Element.— In chemistry is a substance that cannot be separated into other substances. Thus gold is an element; you may divide it into very min- ute portions, but each piece, no matter how minute, is still gold. Common table salt is not an element, but can be separated into two very unlike substances which areelements. There are only alittle over sixty elements known to chemists to-day.
The term element is often used to represent one of the ingredients in a complex compound —as in the expression, ‘The elements lacking in the fertilizer were ammonia and potash” —though neither ammo- nia nor potash is an element in the chemical sense of the term.
§ 2. The Foundation of Science.
22. All science is founded on the principle that matter is subject to certain definite and unchangeable laws, which may be ascertained, and when ascertained will enable us to know positively the results of cer- tain causes. Science may be said to rest on the prin- ciple that every effect must have a cause, and that the same cause, under the same circumstances, will always produce the same effect. If it were not for
20 SCIENCE IN FARMING.
this principle, scientific progress in any work would be impossible.
23. Ifa substance is left unsupported, we know it will fall directly toward the earth. No other action is possible. The fact that wood will float in water, and smoke ascend in the air, is not an exception, as the wood is supported. by the water, and the smoke by the air.
24. Ifa farmer gets 30 bushels of wheat per acre on one field, and only 10 bushels per acre on another, the difference is not due to an accident, or a whim of the crop; but toa different condition of circumstances in the two fields. If he can learn what was the cause of the good crop in the one field, and secure that cause in the other, he will be certain of as good a crop. Of course, in practice it is not possible for the farmer to control all the circumstances that affect a crop, but just so far as he can control those causes he can con- trol the result.
25. A knowledge of science is therefore a knowl- edge of the properties of bodies, of the laws that gov- ern their action upon each other, and the relations that exist between cause and effect.
§ 3. Arithmetic.
26. Science being exact, much of its rosie are to be determined only by paca calculations, and it will be difficult, if not impossible, for the student to _master any science without knowing something of the rules of arithmetic. We shall assume, therefore, that the readers of this book are at least moderately fa- miliar with arithmetic, and call their attention to two divisions of it only.
27. Per Cent.—By per cent is meant the number of parts in a hundred. Thus, in 100 lbs. of good milk
SCIENCE IN ITS ELEMENTS. 21
there are about 87 lbs. of water; so we say that milk is 87 per cent water.
28. The percentage composition of a substance is the number of parts of each constituent in 100 parts of the substance. A great many scientific tables are pre- pared, giving the percentage composition of sub- stances.
29. When we know the per cent of any constituent and wish to learn the exact amount of that constit- uent there would be in a given amount of the sub- stance, we multiply the amount of the substance by the per cent of the constituent, and divide by 100.
Thus we find that fat forms about 32 per cent of the whole carcass of a fat ox. Now, if we wanted to know how many pounds of fat there were in a fat ox weighing 1,475 lbs., we would proceed thus: 1475 To divide by 100, we only need to strike off 29 the two last figures to the right, and call them hundredths, and so we get the answer, that an 2940 ox weighing 1,475 lbs., whose carcass was 82 4425 per cent fat would contain 471% Ibs. fat 471.90
30. Decimals.—It is found very convenient in scientific calculations to use principally decimal fractions—that is fractions represented in tenths, hun- dredths, thousandths, and so on. Decimals are writ- ten by putting a period after the figures denoting the whole numbers, and to the nght of this the figures representing the number of tenths, hundredths, thou- sandths, as the case may be. One figure to the right of the period stands for tenths; two figures for hun- dredths, and three for thousandths.
Thus 1.9 would be read “ one and nine-tenths;” 1.93 “one and ninety-three one-hundredths;” and 1.016, “one and sixteen one-thousandths.” A cipher an-
29 SCIENCE IN FARMING.
nexed to the right of a decimal does not change its value; thus, 1.90 would read “one and ninety one- hundredths,” which of course is the same as one and nine-tenths. A cipher placed to the left of a decimal reduces its value to one-tenth what it-was in the for- mer place; thus, 1.09 would be read “ one and nine one-hundredths.”
31. It frequently happens that a decimal is used without a whole number; thus, it is said that a good soil contains .25 per cent of nitrogen, which means that it contains twenty-five one-hundredths of one per cent, or a quarter of a pound of nitrogen in a hundred pounds of soil.
CHAPTER ITI. SCIENCE IN HEAT AND ENERGY.*
$1. Their Nature. «
32. The Same Principle——Heat and energy are dif- ferent manifestations of the same principle. Heat is said to be a mode of motion. Heat can be changed into energy, and energy may be changed into heat.
33. Illustrations. —If a bar of iron is hammered on an anvil, the energy that was used will be expended, and the bar of iron will become hot, and the amount of heat in the iron will be in exact proportion to the amount of energy expended in the blows. If heat is applied to a steam boiler, and the steam produced used in running an engine, the heat of the fire will be ex- pended, but instead we have the motion of the ma- chinery. If a brake is applied to some part of the machinery and the motion is stopped, the brake will become hot, and the heat will be in exact proportion to the amount of energy that had to be overcome. .
If a pound of ice at 32 degrees is broken and mixed with a pound of water at 174 degrees, the ice will be entirely melted, and the temperature of the two pounds of water will be but 32. One hundred and forty-two degrees of heat will have been lost by the
*The word energy is here used to represent what might be called active force, force producing work.
24. SCIENCE IN FARMING.
pound of water, and the temperature of the pound of water produced from the pound of ice will be no higher than that of the ice. The heat had been changed into the energy needed to overcome the attraction of the particles of the solid ice and change it into a liquid.
384. If heat is applied to a quantity of water the temperature of which is 32 degrees, it will gradually erow hotter until it reaches 212 degrees; then the water will begin to boil or be changed into steam, but the temperature of the steam will be no higher than that of the water had been. If the heat is uniform, it will take five and a half times as long to change the water into steam as it did to raise the water from the freezing to the boiling point. This heat has been changed into the energy needed to overcome the attrac- tion 6f the particles of water for each other and change the liquid into a vapor.
35. When water is poured on quicklime, they unite chemically, and the water becomes part of the solid slaked lime. The energy that had before kept the atoms of water separated is now changed into heat, and the mixture is hot, though both the lime and the water were cold before mixing.
36. Place a pan of hot water out of doors on a cold winter day. The temperature of the water will fall until it reaches the freezing point and the water be- gins to freeze. Then it will remain unchanged until all the water is frozen. The energy that has before been keeping the atoms of water separated is con- verted into heat, as the water becomes solid, and pre- vents the further fall of temperature until all the water is changed into a solid.
37. Cannot be Destroyed.—Heat and energy can nel- ther be destroyed nor created. In an elementary
HEAT AND ENERGY. 25
work, such as this, it would be impossible to fully ex- plain and illustrate this fact; but it is an important one. Heat and energy must always be derived from some source where they have previously been stored. The energy that moves our locomotives and keeps our factories running, was received from the sun long ages ago, in the form of heat and light, stored up by grow- ing plants, and is now changed into energy in the fur- naces and fire-boxes.
38. The heat that keeps an animal alive, the force which he expends in work and motion, are not created by the animal, but are obtained from the food, and were originally gathered from the sun. This last fact will be more fully explained in the chapter on Animal Life.
39. Specific Heat.—If a pound of water and a pound of mercury are both exposed to a uniform source of heat, it will require thirty times as long to raise the temperature of the pound of water a given number of degrees as to raise the temperature of the pound of mercury the same number of degrees. That is, the water requires thirty times as much heat to raise its temperature a given number of degrees as would be required by an equal weight of mercury. Kach substance requires a particular amount of heat, peculiar to itself, and this amount is called the spe- cific heat of the substance.
The reason for this cannot be explained in this work. § 2. Transference of Heat.
40. Heat moves, or is transferred from one place to another by three methods, called conduction, con- vection and radiation.
26 SCIENCE IN FARMING.
41. Conduction.—If one end of a bar of iron is placed in the fire, the heat will pass through the iron, and the other end will become hot. This is called conduction.
42. Difference in Conduction.—If two similar rods, one of copper and one of iron, are heated at one end, it will be found that the heat will pass through the copper more rapidly than through the iron, and the copper is said to be the better conductor. Substances through which heat passes readily are called good conductors ; those through which it passes slowly are called bad conductors. All metals are good conduc- tors. Liquids and gases are very poor conductors, so poor that they are often called non-conductors. Snow is a very poor conductor; hence when the ground is covered with snow, the heat it contains does not escape, and thus snow protects the crops.
43. Convection When heat is applied to the bot- tom of a vessel containing water or some other liquid, the particles in immediate contact with the vessel become heated; this causes them to expand and be- come lighter, and they rise to the upper part of the vessel while the colder portions sink, and in this man- ner all the liquid in the vessel becomes heated. This is called convection. Gases are heated in the same manner. The portion in immediate contact with the heated substance becomes warm and rises, and a cir- culation is thus established.
44, Radiation.—If we stand near a stove or other heated body, we feel the heat from it, though it is not conveyed to us either by conduction or convection. All bodies are constantly throwing off heat in straight lines, like light. This is called radiation, and heat thus transferred is called radiant heat. Radiant heat
HEAT AND ENERGY. rat
passes through the air or any gas without imparting warmth to it.
45. Radiation is influenced by the color and sur- face of the body—a dark, rough surface radiates heat more rapidly than a white or polished one. Hence a brightly polished coftee-pot will keep coffee hot longer than one that is dark and rough.
46. Absorption of Heat.— When radiant heat strikes a body it is, to a greater or less degree, absorbed by that body, and warms it. The same surfaces that ra- diate heat readily also absorb it readily. If a black cloth anda white one are spread on the snow in the sun, the black one will rapidly absorb the sun’s heat and melt the snow beneath it, while the white one will not. So ablack hat is warmer in the sun than a white one, and a black soil gets warm more quickly in the spring than one of a lighter color.
§ 3. Practical Application.
47. Ifajug of water in the harvest field is covered with a thick cloth soaked with water, the heat of the sun and air will be converted into energy to change the water in the cloth into vapor, and the water in the jug will remain cool until the water in the cloth has been evaporated.
48. A wet cloth worn inside the hat protects from the sun’s heat. The British troops in India were ena- bled to endure the heat only by constantly wearing a wet cloth over the head. A shawl or woolen cloth hung in the window of a room and kept wet, will lower the temperature several degrees. Sprinkling the walks, grass and trees around a house imparts a delightful coolness to the air on a summer day. These effects are caused by the conversion of heat into ener- gy, required to change water into vapor.
28 SCIENCE IN FARMING.
49. Perspiration protects from heat in the same manner. If an animalin winter is caused to perspire unduly by the use of food containing an excess of water, heat is wasted.
50. When the ground is filled with water, the heat of the sun, instead of warming the soil, is converted into the energy required to convert that water into va- por, or in other words, the heat is used for pumping instead of for warming. Hence advocates of drainage tell us that it lengthens the season.
51. Ifaroom is heated by an open fire, the radiant heat from the fire does not warm the air of the room, which can only be warmed by coming in contact with the walls and furniture that have been heated by the fire. Hence a grate or fire-place warms a room but slowly, and the fire may feel uncomfortably hot while the air of the room is yet cold.
A. stove radiates heat less rapidly than an open fire, but warms the air by convection. Hence an open fire is better for warming the walls and furniture of a room and so removing dampness; but a stove warms the room more uniformly.
52. ‘The sun’s rays pass through the air without communicating any warmth to it. The air is warmed only by contact with the soil. Hence the soil is often several degrees warmer than the air.
53. Though gases allow radiant heat to pass through them readily, yet the minute particles of water suspended in the air will not. The partially con- densed vapor always present in the air prevents the heat that has been absorbed by the earth from being radiated off into space. If it were not for this protec- tion the earth would be uninhabitable.
54. In the same way, and to a greater extent,
HEAT AND ENERGY. 29
clouds prevent the radiation of heat into space, and so in a cloudy night in fall and spring there is little risk of frost. Thus it is that the intensely cold nights of winter are usually those when there are no clouds and the air is very dry.
55. In fruit-growing districts crops are often saved on nights when frost is threatened, by building fires that will produce a heavy mass of vapor and smoke that hangs like a cloud over orchards and vineyards. In some places arrangements have been made by the government weather stations by which warning of approaching frosts is sent to the fruit-growers who have their fires built ready to be lighted if needed.
COB AgE Eis Va.
CHEMISTRY.
S1. ts Nature and Language.
56. Chemistry treats of the composition of bodies, the changes that are occasioned by their combination, or the separation of those already combined, and the laws that control those changes.
To understand chemistry, it is first necessary to learn something of the language and terms used.
57. Chemical Combination—The word combination in chemistry means something more than it does as usually employed. It indicates not only a bringing to- gether of certain substances, but such a union of those substances that their whole nature and character is changed.
58. For example, quicklime is a white, caustic solid; oil of vitriol is an oily liquid, intensely sour, and burns and corrodes whatever it touches. If 56 Ibs. of quicklime, 98 Ibs. oil of vitriol and 18 lbs. of water are mixed, they will combine chemically and we will have 172 lbs. of land plaster, which bears scarcely any resemblance to the substances of which it was made. In this combination 116 lbs. of liquids were added to 56 lbs. of a solid and the result is a per- fectly dry solid. Thiszis the result of chemical com-
CHEMISTRY. 31
bination, which is entirely different from a simple mixture.
The air we breathe is a mixture of two gases, but were those two gases to enter into chemical combina- tion, all life would perish from the earth.
59. Chemie Force —The power that causes sub- stances when brought together to enter into chemical combination is called chemism, or chemic force, or af- finity. The last term is however less used now.
60. This force does not apply equally to all sub- stances—there are some that cannot be compelled to enter into chemical union at all, while others unite as soon as brought together.
61. When two substances are united and a third is added, it may displace one of the others. Thus, if quicklime is exposed to the air, it will, in time, unite with the carbonic acid contained in the air, forming carbonate of lime. If to this vinegar is added, it will combine with the lime and set the earbonic acid free.
62. Acids and Bases.—It would be impossible to ex- plain the strict chemical definition of these terms to the unscientific reader without devoting to it more space than can be given in this work. The statement that an acid is a compound of a non-metallic element with hydrogen and oxygen, and that a base is a com- pound of a metal with hydrogen and oxygen, is very nearly the scientific definition.
In popular language the term acid is applied to any substance that has a sour taste, and that readily enters into combination with the oxides of the metals, and a base is a metallic oxide. Both acids and bases in their ordinary condition contain the elements of water.
63. Acids and alkalies are distinguished by the
32 SCIENCE IN FARMING.
fact that acids turn blue litmus paper red, and alka- lies restore the blue color. Litmus paper is made by soaking blotting paper in a solution of litmus and drying it. Litmus is a blue substance obtained from a lichen. Litmus paper is the common test to deter- mine whether a substance is acid or alkaline.
64. Exceptions—Ammonia, which is not the oxide of a metal, possesses so distinctly all the character- istics of an alkali that it is universally recognized as such, and hydric chloride, though containing no oxy- gen, has all the properties of an acid, and is commonly known as muriatic acid.
65. Salts—Compounds produced by the union of an acid and a base. According to chemical lan- guage common table salt is not a salt.
66. Solution—When sugar is placed in water it eradually disappears, and we say it is dissolved. When finely powdered chalk is stirred up with water it remains for a time mixed with, or suspended in the water; but if the mixture is allowed to remain undis- turbed, the chalk will finally settle to the bottom. The first case is an instance of solution; the second, of mixture or suspension. Rivers often carry, sus- pended in their waters, large quantities of mud and sand, and also, in solution, salts that have been ob- tained from the soil.
67. A substance that will dissolve in water, such as salt or sugar, is called soluble. One that will not dissolve in water, such as sand or chalk, is called insol- uble. Many substances that are commonly called insol- uble, are really soluble, though only to a slight extent.
68. Some substances will dissolve in one liquid but not in another. Common resin will not dissolve in water, but readily dissolves in alcohol. .
CHEMISTRY. 33
69. Water containing other substances in solu- tion will sometimes dissolve substances that are ordinarily insoluble. Thus water containing carbonic acid and certain organic acids will dissolve many sub- stances that are usually quite insoluble, and thus pre- sent them as food for plants. This is commonly the result of chemical action. Thus chalk will not dis- solve in pure water, but if vinegar is added, the chalk is dissolved. In this case the vinegar combines with the lime in the chalk, forming a soluble com- pound.
70. Substances when not combined are called “free.” Thus we speak of the free nitrogen of the air, and the combined nitrogen in albumin.
71. Organic Substances—Compounds that are pro- duced under the influence of animal or vegetable life, are called organic compounds. Thus sugar, starch and gum are organic substances. So also are albu- min, fat, etc. In general, the term organic is applied to all animal and vegetable substances.
§ 2. Chemical Laws.
72. Combining Proportions.— Substances may be mixed together in all proportions, but chemical com- bination always takes place in fixed and definite pro- portions. This may be illustrated in three of the most common elements — carbon, oxygen and hydro- gen. Hydrogen and oxygen will combine by weight in the proportions:
a LEE CO RA EA ape a A Gea) bea Oe BORE 16 parts.
EUG NTO7 21s ane ae ele Pay Pe ae ee 2 parts. Or;
CEL SIP RIS ee Sereeeerar ene ne Orne Pelee ae 32 parts.
RA MPNEOOIR ae cic 2 4s Mana ane Seas nes 2 parts.
If 16 lbs. of oxygen were mixed with 3 lbs. of hy-
vo
34 SCIENCE IN FARMING.
drogen and the mixture caused to unite chemically, the oxygen would combine with 2 Ibs. of the hydro- gen, forming 18 lbs. of water, and the 1 lb. of hydro- gen would be left uncombined.
73. Carbon and oxygen will unite in the propor- tions:
Carbon...) 12 parts, Oxygen .... 16 parts. Carboni) caer 12 parts. Oxygen .... 32 parts.
74. Carbon and hydrogen combine in numerous proportions, but they are all such as:
Carbone caus. 12 parts. Hydrogen. <4 yc 4 parts. Carbone. 5. 24 parts. Eivdrogeni cei: an 4 parts. Carbon," 2. >: 24 parts. Hydrogen "2% 2 parts.
It will be seen that in all these cases carbon enters into combination in the proportion of 12, 24, and so on; hydrogen, 1, 2,3, and so on, and oxygen, 16, 32, 48, and so on. Every element has some definite pro- portion in which it always enters into combination.
75. Atomic Theory.—This property of matter is ex- plained by what is called the atomic theory. It is supposed that the atoms of which each element is composed (18) are always of exactly the same weight, but that the atoms of different elements have different weights. When elements unite chemically, it is due toa union of the atoms. One atom of an element may combine with one, two, or more atoms of another element; but as an atom is something that cannot be divided, it is impossible for atoms to combine with fractions of atoms.
76. Ifan atom of carbon weighed 12 ounces, and an atom of oxygen 16 ounces, and an atom of hydro- gen 1 ounce, it follows that a combination of oxygen and carbon must be in the proportion of 12 to 16, or 12 to 32; that a combination of hydrogen and oxygen must be in the proportion of 1, or 2, or 3, or 4 of hy-
CHEMISTRY. 35
drogen to 16 or 32 of oxygen, and this is the case. We cannot know what is the actual weight of an atom, but the relative weights of the atoms of all the elements have been ascertained, and as the atom of hydrogen is the lightest of all, it is taken as the stan- dard, and the weight of the atom of an element, as compared with the weight of an atom of hydrogen, is called the atomic weight of that substance. And thus we say that the atomic weight of hydrogen is 1, of carbon 12 and of oxygen 16.
77. Molecular Weight—When the atoms of two or more elements combine, they form a compound atom called a molecule.* Ofcourse the weight of this mol- ecule will be that of the combined weight of all the atoms of which it is composed. Thus carbon dioxide is composed of:
SOMA, Car WON, “Wel S24 8G we dese aida es Bad ae 1s Pasomn oxygen, weighing 16 each). .'.4°. <0. ays ke. 32 Making 1 molecule carbonic dioxide weighing..... 44
This is called the “molecular weight” of the com- pound. When compound bodies enter into combina- tion, they always do so in the proportion of their mol- ecular weight. Thus, the molecular weight of car- bonic dioxide, is as we have seen 44; that of calcic oxide (quicklime) 56, and when these two combine it will be in the proportion of 44 parts, by weight, car- bonic dioxide, and 56 parts, by weight, calcic oxide, forming 100 parts of calcic carbonate—or carbonate of lime.
78. Equivalents.—In the older chemistries, the word equivalent was used to represent the same idea that is now represented by the words atom and molecule.
*The word is derived from a Latin word meaning a little mass.
36 SCIENCE IN FARMING.
Thus, carbonic dioxide was said to be composed of one equivalent of carbon and two equivalents of oxygen, instead of one atom of carbon and two atoms of oxy- gen; and calcic carbonate was said to be composed of one equivalent of carbonic dioxide and one equivalent of lime instead of one molecule of carbonic diox- ide and one molecule of lime. The word equiva- lent was also used to represent atomic and mol- ecular weight. Thus it was said that the equiv- alent of carbon was 12, of carbonic dioxide 44, and so on. The term is about discarded, but is still occasionally seen.
79. Application—A knowledge of the atomic and molecular weight of bodies enables us to know the proportions in which these substances are contained in their compounds. Thus we learn that tricalcic phosphate (commonly called bone phosphate) is com- posed of three molecules of lime, and one molecule of © phosphoric acid. The molecular weight of lime is 56, of phosphoric acid 142 (when in combination) so we know the composition of tricalcic phosphate to be:
3 molecules lime weighing 56 each ........... 168 1 molecule: phosphoric “acids loniLs.< 20 see 142 Making 1 molecule tricalcic phosphate ....... 310
And we know that the phosphate contains 342ths of its weight of phosphoric acid.
A knowledge of these facts also enables us to know in what proportion chemicals should be used to secure certain results.
§ 3. Chemical Symbols and Formula. 80. Symbols——For convenience in representing the composition of bodies, chemists have adopted certain signs, each of which represents an element, and is
CHEMISTRY. 49%
called its symbol. Usually the first letter of the name is used—thus C stands for carbon, O for oxygen, H for hydrogen. When the names of two elements begin with the same letter, the two first letters of one are used— as Ca for calcium. Sometimes the first letter of the Latin name of the element is used, as K for potas- sium, the Latin name of which is kalium.
81. A compound is represented by writing together the symbols of all the elements it contains. Thus CO would represent a compound of carbon and oxy- gen. HSO a compound of hydrogen, sulphur and oxygen. |
82. The symbol not only represents the element, but exactly one atom of that element. Thus CO would represent a compound composed in the propor- tion of one atom of carbon and one atom of oxygen. When it is desired to represent more than one atom of an element, it is done by placing a small figure after the symbol and a little below it. Thus CO, rep- resents a compound of one atom of carbon and two atoms of oxygen. The symbols representing the com- position of a substance are called its formula. Thus CO, is the formula of carbonic dioxide. In this way the chemical composition of a substance can be stated with an accuracy, clearness and brevity not otherwise possible. When more than one molecule is to be rep- resented, it is done by placing a large figure before the formula of that molecule, thus CaSO,2(H,O) represents a compound containing one molecule of calcic sulphate, and two molecules of water.
$4. The Elements.
83. Of the sixty-three elements known to chemists agriculture deals with only fifteen. We give the list of these with their symbols and atomic weights:
38 SCIENCE IN FARMING.
Name. Symbol. Atomic Weight. ORV PER: Ht at ae PO oe led ai ee 16 Hydrogen... 2346 0. eee elec GAs A gaa ae eae I 1 Nitroven™): 0/20). ae eee SNS ATS CRS Oh eae tL 14 Chigrine:|} a3. 0 a eee Ce OS RE wnt} ALA 35.5 Carpon.. ine coke oe OE en ie eRe 12 Phosphorus .)). 200), ae tar enta lat) ee eta Oe Ad 31 OLUURGY GWU EyALaP Miamiere Geum A Spano! 7 MMT S rel Lalo Sashes 32 ROU UATCEra) o Weep INO ole Manet ho A i Ae Pe 2 ean Ran lace iigh 28 Potassiim hear 1 SAW AE Ta tite Mas Sap pA aes tine 39.1 BOCA, nis CUE ECR tar gS Naren. (at stone Weds Murcer ae 23 (Calero Shree oe etre inian le, Oia pein is rie enn ie aie Se 40 NAPE RIAA RS. sues es ii etek eae Pete! 24 ANA. ik eden) Wek a AT pasos SE) Oe et ace ie eee eee grasp ea a Np a kuet keys oes ine TR GE ve le te tt, gt gem ea 56 MAM@ARESE tia oi ld Yee: MET ER tas oe ee 5d
The first four are gases, the next four non-metallic solids, and the last seven metals. This being a work on agriculture, and only treating on chemistry so far as necessary to a comprehension of the science of farming, we devote no space to the other elements, and consider the fifteen named specially in view of their importance to the farmer.
84. Oxygen.—A gas that forms about one-fifth of the atmosphere. It very readily unites with a great number of other substances. It was formerly called ‘vital air,” as without it animals could not live and fires could not burn. Any substance that will burn in the air will burn more readily in this gas, and even substances that will not usually burn at all, such as a piece of iron wire, or a steel watch spring, will burn brilliantly in a jar of this gas. An animal when drowned dies from lack of oxygen, and fires are checked by excluding oxygen. An animal confined in the pure gas becomes excited and feverish, and soon dies from over excitement. Oxygen causes. the decay of animal and vegetable substances, and with-
*From Kalium. +tFrom Natrium. +From Ferrum.
CHEMISTRY. 39
out it fermentation and decay cannot take place. Fruit keeps in air-tight cans and ensilage in silos because the oxygen of the air is excluded. Though the pro- moter of fermentation and decay, it is also the great purifier, for where oxygen is supplied in abundance decay is rapidly carried so far that the material is re- duced to harmless forms. Oxygen is necessary not only for animal but also for vegetable life. It is one of the most abundant of all elements, forming one- fifth of the atmosphere, eight-ninths of the water, and a large proportion of all rocks.
85. Hydrogen.—The lightest known substance. A cubic foot of it weighs only one-sixteenth as much as a cubic foot of oxygen. It can be breathed without injury, but an animal confined in the pure gas would die from lack of oxygen. It burns with a blue flame, and with air or oxygen gas forms a very explosive mixture. It is never found in nature except in com- |
*bination.
86. Nitrogen.—This gas forms about four-fifths of the air. It will not burn, and though not poisonous an animal confined in the pure gas will die from lack of oxygen. It does not readily enter into combination with other elements, and except in the air is not abundant. It is an essential element however, in many organic substances.
87. Chlorine.—A greenish yellow, heavy, poisonous gas, never found in a free state in nature. Oneof the elements of table salt. Used for bleaching and as a disinfectant.
88. Carbon.— Well known in three forms: charcoal, black lead and diamond. The first two are nearly pure, the last perfectly pure carbon. Contained in nearly all organic matter. It forms more compounds
40 SCIENCE IN FARMING.
than any other element. At ordinary temperatures it will not enter into combination with any other ele- ment, and is completely insoluble. When uncom- bined it is therefore without value as food for either plant or animal. When heated in the air it takes fire and burns, combining with the oxygen of the air to form carbonic dioxide—which readily enters into fur- ther combination and is the source from which the carbon in all its compounds is obtained.
89. Phosphorus.—A waxy yellow substance that burns so readily it is usually kept under water. Used in commerce in the manufacture of friction matches. Combined with oxygen and hydrogen it forms phos- phoric acid, a substance of great agricultural impor- tance.
90. Sulphur.— Well known as “brimstone,” or ‘* flowers of sulphur.” It is contained in some organic substances. With oxygen and hydrogen it forms sul-, phurie acid.
91. SiliconA brown solid, known only in combi- nation.
92. Potassium, Sodium, Calcium and Magnesium.— Metals known only in their compounds, which will be described in the next section.
93. Aluminum.—<A hard white metal of considera- ble value in the arts. In combination with silicon and oxygen it forms common clay.
94. Iron.—In some form iron is necessary to the life of plants and animals. It forms two compounds with oxygen—one called the black oxide, the other the red oxide. Substances containing the first oxide are injurious to vegetation, and soils containing it are therefore unproductive. By exposure to the air the
CHEMISTRY. 41
black oxide is converted into the red oxide, which is of much value.
85. Manganese.—A metal resembling iron, but of much less importance. Its compounds cannot take the place of those of iron in the soil.
§ 5. The Compounds.
96. In describing compounds we shall use the chemical symbols and formula, for the double reason that they can be more clearly and briefly represented in that way than in any other, and that it will be good practice for the student. It will be well for the student to refer to the table of atomic weights, and calculate for himself the proportion of each element contained in a compound. Thus we shall give the composition of sulphuric acid as H,SO,. A molecule of it is therefore composed of
2 atoms of hydrogen, weighing 1 each................ 2 Pera or SOIpDNUr, WeIphing o. ..i6 6 ope cae ey wae le oe ae 32 4 atoms of oxygen, weighing 16 each.................. 64 Making one molecule of sulphuric acid, weighing...... 98
Sulphuric acid is therefore composed, by weight, of ggths hydrogen, ths sulphur, and $4ths oxygen.
The formula of starch will be given as C,H,,Q;. From this we learn a molecule of it contains
Gatoms Carbon, weighing 12 each. 1... 2 10/atoms hydrogen, weighing | each ........00..0.45.. 10 pups Oxygen, weighing 16 each. 2250. oon. ba ees 80 Making one molecule of starch, weighing............. 162
Which shows the proportion of each element con- tained in starch.
Suppose, for example, the reader wishes to know how many pounds of nitrogen are contained in a ton of sodic nitrate, commonly called nitrate of soda—a
49 SCIENCE IN FARMING.
popular fertilizer. Its formula is given as NaNOsg. It is therefore composed of
1 atom. SOGLUIN, Wyler Wet apa Cet tain, eek eee 23 I AtOMt DIGPOSEM, Wiehe nme ek 4 i's rece 6 soca 14 S atoms Oxygen, welshune goiGach 654 oe 48 Making one molecule sodic nitrate, weighing.......... 85
A ton of it therefore contains }4ths of a ton of nitro- gen, and the number of pounds of nitrogen in a ton would be determined by multiplying 2000 (the num- ber of pounds in a ton) by the numerator of the frac- tion, and dividing by the denominator. Thus: A ton of pure nitrate of soda therefore contains 32934 Ibs. of nitrogen. 14
97. Water—H,0. Mol. Wt.18.* Wa —- 70000 ter is the great natural solvent by 85 )28000(329 which plants and animals obtain their O55 food. Its elements are also contained
in a large number of organic and inor- 250 ganic substances. It is commonly re- 170 ferred to in four forms: water of combi- 800 nation —as it exists in land _ plaster, 165 which contains a little over one-fifth of a its weight of water in combination; “ hy- 35
drostatic water,” which means water
that will flow out of the substance containing it, if opportunity is afforded; capillary water, that which is retained within the pores of a substance and will not flow out, but is still perceptible to the senses; and hygroscopic water, that which is not perceptible to the senses, but can be driven out by heat. Nearly all substances that have been dried in the air contain hygroscopic water.
*Henceforth we shall use the abreviation At. Wt. for atomic weight, and Mol. Wt. for molecular weight.
CHEMISTRY. 43
98. Ammonia.—NH,. Mol. Wt.17. A colorless gas, with a peculiar, pungent odor, often perceived about stables and manure heaps. Itis very valuable as a fer- tilizer, and will be further considered in succeeding chapters. Being a gas, it readily escapes into the air and is lost. Water absorbs it readily, and a strong solution of it forms the “aqua ammonia,” “ spirits ammonia” of the drug stores. In this form it is val- uable in the household. It is useful in place of soap, in cleaning paint, removing grease, etc. A little added to the water for the bath has a very refreshing effect. A few drops, given in water, makes an excel- lent stimulant in cases of fainting, poisoning, etc. A tea-spoonful added to a quart of water, is an excellent fertilizer for pot plants, but caution should be exer- cised not to use too much. It is often retailed at 5 or 10 cents an ounce, but can be bought at wholesale at from 4 to 6 cents a pound.
99. Carbonic Dioxide. —CO,. Mol. Wt. 44. Commonly called carbonic acid. A gas with a sour taste. About one-half heavier than the air, which contains about xeath of its weight of this gas. When breathed in quan- tity it is highly poisonous, but the small amount present in the air is not injurious to animals, and is essential to vegetable life. It is given off in the breath of all animals, and by the fermentation or de- cay of organic matter. When wood or coal is burned, the carbon it contains unites with the oxygen of the air, producing this gas. Hence, if the smoke and gas from a fire are allowed to escape into a room, the air becomes poisonous. Lamps burning in a poorly ven- tilated room soon produce an injurious amount of this gas. Itis the amount of this gas given off in the breath that makes the air grow foul in crowded rooms unless
44 SCIENCE IN FARRMING.
abundant ventilation is provided. Water absorbs this gas freely, and though poisonous when breathed, its solution in water is both palatable and wholesome. Spring water owes its sparkling to the presence of this gas. The water in the soil always contains this gas in solution. Water containing this gas will dissolve many substances not otherwise soluble, and thus pre- pare them for the food of plants. Hard water usually owes its hardness to limestone, which will dissolve in water containing cabonic acid, but not in pure water. As boiling the water drives off the gas, kettles in such regions of country soon become crusted with a coating of lime. Carbonic dioxide forms many compounds with bases, which are called carbonates.
100. Phosphoric Acid—H,PO,. Mol. Wt. 98. This is really a compound of phosphoric pentoxide (P,O; ) with three molecules of water, and is sometimes writ- ten thus: P,0,3(H,O) Mol. Wt. 196. In its combi- nation with bases, one, two, or three molecules of water are replaced by one, two or three molecules of a base, and the compound is called a phosphate. Phosphates containing one molecule of base and two of water are distinguished by the prefix mono; those containing two molecules of a base and one of water, by the prefix bi; and those containing three molecules of base by the prefix tri. This will be more fully ex- plained later in this chapter. In analyses of foods and fertilizers, the term “ Phosphoric acid” is used to represent P,O,, called by chemists phosphoric pent- oxide.
101. Nitric Acid—HNO,, Mol. Wt. 63. Known in the drug stores as “aqua fortis.” It is formed toa small extent in the atmosphere by the direct combi- nation of its elements under the influence of electric-
CHEMISTRY. . 45
ity, and combines with the ammonia in the air, and is washed out by the rains. It is also formed to a consid- erable extent in the soil under certain circumstances by the oxidation of ammonia and organic substances containing nitrogen. Its compounds with bases are called nitrates.
102. Sulphuric Acid—H,.SO,. Mol. Wt. 98. A heavy, oily liquid, commonly known as oil of vitriol. A pint weighsa little over 13 tb. — It is very corrosive, burning and destroying most forms of organic matter. It should always be handled with great care. When mixed with water great heat is produced, and it is a dangerous experiment when incautiously done. In making the mixture, the acid should always be poured into the water, and never the water into the acid. It is usually sold in large glass vessels called carboys, and costs from 14 to 3cents a pound. Its compounds with bases are called sulphates.
103. Silicic Dioxide —SiO,. Mol. Wt. 60. Com- monly called silica and sometimes silicic acid. It is commonly known as quartz, flint, ete. Nearly all rocks contain it. Water containing certain organic substances dissolves it to asmall extent, and it is thus taken up by the plant with its food. Its compounds with bases are called silicates.
104. Potassic Hydrate—KHO. Mol. Wt. 56.1. An exceedingly caustic substance sold in the drug stores as caustic potash. It is always present in good soils, and is essential to vegetable life. Itis a large constit- uent in ashes, and gives them their value as a manure. It is contained in many rocks, which, by their decay, supply it to the soil. A mineral called kainit con- tains it in large quantities and is now extensively used as a fertilizer. The term “ potash,” as used in
46 SCIENCE IN FARMING.
giving the analysis of foods and manures, means K,O, called by chemists potassic monoxide, a substance usually known only in combination.
105. Sodic Hydrate —NaHO. Mol. Wt. 40. Caustic soda. It is used by plants to but a small extent, and cannot take the place of potash in the soil.
106. Sodic Chloride——NaCl. Mol. Wt. 58.5. Com- mon table salt.
107. Calcic Oxide.—CaO. Mol. Wt. 56. Quicklime. Obtained by burning chalk or limestone, (calcic car- bonate.) This is a compound of lime and carbonic dioxide, and when exposed to heat the latter is driven off and the lime remains. Quicklime readily unites with water, forming slacked lime, with the formula H,CaO,. When quicklime is exposed to the air, it gradually absorbs water and falls into a white powder —slacked lime. It also gradually absorbs carbonic dioxide and returns to its original condition of calcic carbonate. Hence, when lime is kept, it is necessary to exclude the air as much as possible. When applied to the soil it is very rapidly converted into carbonate of lime, but ina much finer powder than it could pos- sibly he reduced to by any other means. Lime is of value as food for plants, and it also has other proper- ties which will be more fully considered in the chap- ter on fertilizers. It has a strong “affinity” for all acids, and when mixed with a salt, will frequently combine with the acid it contains and set free the base with which it had been previously combined. Thus, if sulphate of ammonia and quicklime are mixed, the result will be sulphate of lime and free ammonia, which, being a gas, will escape. Hence, lime should not usually be mixed with the manure heap.
CHEMISTRY. 47
§ 6. Compounds of Acids and Bases.
108. Nitrates——Nearly all the compounds of nitric acid are soluble. The only ones of importance to the farmer are potassic nitrate, (IMNO,, Mol. Wt. 101.1) commonly known as nitrate of potash, or saltpeter, and sodic nitrate, (NaNO,, Mol. Wt. 85,) commonly called nitrate of soda, or Chili saltpeter.
Nitrate of potash occurs in abundance in the soils of some tropical countries, and is also produced arti- fleially in what are called “saltpeter plantations.” Heaps of soil and organic matter containing nitrogen, are made, with lime or potash in some form, and left for many months to decompose — being kept con- stantly moist. The nitrogen in the organic matter combines with oxygen from the air, forming nitric acid, which combines with the potash or lime in the soil, forming nitrate of potash or lime. This is after- wards dissolved out by water, and when purified be- comes the saltpeter of commerce. It is too expensive for use as a fertilizer, but its formation naturally in the soil is a matter of great importance.
Chili saltpeter derives its name from the fact that it is imported in large quantities from South America. It is largely used as a fertilizer to supply nitrogen to the soil. It contains about fifteen per cent of nitrogen?
109. Sulphates——Calcic sulphate dihydrate, CaSO, 2(H,0), is commonly known as gypsum, or land plaster. It is used as a manure, and furnishes both sulphuric acid and lime to the plant. The method of its action as a fertilizer is not well understood. When added to matter containing carbonate of ammonia, an exchange takes place—resulting in sulphate of ammo- nia and carbonate of lime. This makes it valuable for use in the manure heap and about stables to pre-
48 SCIENCE IN FARMING.
vent waste of ammonia. When gypsum is heated it parts with the two molecules of water, and is converted into calcic sulphate (CaSO,) or plaster of Paris.
Ammonic Sulphate, 2(NH,)SO,, Mol. Wt. 182,— Sulphate of ammonia. Largely used as a fertilizer on account of the large proportion of nitrogen it con- tains, amounting to about 21.2 per cent.
Ferrous sulphate, commonly known as sulphate of iron, copperas, green vitriol. Valuable as a disin- fectant. When it is present in the soil in considera- ble quantity, it is poisonous to vegetation. The addi- tion of lime results in the formation of carbonate of iron and sulphate of lime.
110. Phosphates.—The important compounds of phosphoric acid are those it forms with lime.
Tricalcic phosphate, Ca,P,0,, Mol. Wt. 310. Bone phosphate. Forms about 55 per cent of all bones. Is also found in minerals called coprolite, apatite and phosphorite, of which there are large natural deposits in South Carolina, Canada, England, Spain, and some other countries. It is insoluble, and only available as plant food as it undergoes decomposition in the soil.
Bicalcic phosphate, Ca,H,P,O,. Mol. Wt. 272. Obtained from the tricalcic phosphate by a process that will presently be described. Is slowly soluble, and can be used as food by plants.
Monocalcic phosphate, CaH,P,0,. Mol. Wt. 234. Is readily soluble, and immediately available as plant food.
111. Preparation of Phosphates.—T'o understand the preparation of the bicalcic and monocalcic phosphates, it may be well to represent their composition in this way—keeping in mind that phosphoric acid (using
CHEMISTRY. 49
that term to represent P,O;, called by chemists phos- phoric pentoxide when not in combination) is usually in combination with 3 molecules of water, or some base. Tricalcic phosphate, Ca,P,0,, is equal to CaO CaO; P.O; ca or three molecules of lime and one of phosphorie acid. Bicalcic phosphate may be represented CaO CaO} P.O, ad bi or two molecules of lime, one of water, and one of phosphoric acid. Monocalcic phosphate may be represented CaO H.0) Ore _ H,0 or one molecule of lime, two of water, and one of phosphoric acid. Sulphuric acid, H,SO,, may be represented EO. SO). If we put together one molecule tricalcic phosphate one of sulphuric acid and two of water, they may be represented thus:
1 Molecule 1 Molecule 2 Molecules Tricalcic Phosphate Sulphuric Acid Water. CaO a SO, H,0 on PL0s H,0 H,0 By re-arranging these we can get CaO MO cio P.O, CaO SO; HHO 2
4
50 SCIENCE IN FARMING.
By adding the elements under the first bracket, it will be found they constitute bicalcic phosphate, and by adding those under the second bracket, it will be found they constitute calcic sulphate dihydrate, and thus by mixing bone phosphate, sulphuric acid and water, we get, as the result of the chemical action, bicalcic phosphate and gypsum.
If we add to the tricalcic phosphate double the pro- portion of sulphuric acid and water, the result will be one molecule of monocalcic phosphate and two mol- ecules of calcic sulphate dihydrate. The process of manufacture of the bicalcic and monocalcic phos- phate differs only in the amount of sulphuric acid and water used. The principle is the same in both cases. ‘To aid the student in comprehending the prin- ciple, we will represent the process of making the monocalcic phosphate by words, instead of by symbols.
One Molecule Two Molecules Four Mol- Tricalcic Phosphate. Sulphuric Acid. ecules Water. lal = = ram SSS (a Phosphoric acid Sulphuric acid* Water Linie Sulphuric acid Water Lime Water Water Lime Water Water
This gives us one molecule phosphoric acid, three of lime, two of sulphuric acid* and six of water. They ean be re-arranged thus:
One Molecule One Molecule One Molecule Monocalcic Phosphate Gypsum Gypsum ———$—— ———— eee
Phosphoric acid Lime Lime
Lime Sulphuric acid* Sulphuric acid* Water Water Water
Water Water Water
This subject is of importance because it explains the
*Properly speaking, sulphuric oxide, SOg, sulphuric acid being composed of one molecule sulphuric oxide combined with the elements of one molecule of water.
CHEMISTRY. 51
conversion of bones and rock phosphate into super- phosphate. The practical application, proportions needed, etc., will be given in the chapter on Fertilizers.
112. Carbonates—Carbonic dioxide is readily dis- placed from its compounds by other acids; and ear- bonates can usually be recognized by the fact that they boil up or effervesce when an acid is poured on them, the effervescence being caused by the escape of the carbonic dioxide in the form of gas.
The carbonates that interest the farmer are calcic carbonate (carbonate of lime), and ammonic carbon- ate (carbonate of ammonia). Calcic carbonate is well known as chalk and limestone; it is of some value in the soil. Soils that contain it in consider- able quantity are called calcareous, and may be rec- ° ognized by effervescing when vinegar or some other acid is poured on them.
Ammonic carbonate is a white solid produced by the combination of ammonia and carbonic dioxide. It very readily passes into the form of vapor. It has the pungent odor of ammonia. As manure in decom- posing gives off carbonic dioxide as well as ammonia, the ammonia in manure usually exists in the form of carbonate unless some stronger acid is present to com- bine with the ammonia.
118. Ammonic Chloride—NH,Cl. Mol. Wt. 53.5. Commonly called sal ammoniac. It is used as a fer- tilizer to supply nitrogen of which it contains rather more than ammonic sulphate.
§ 7. Organic Chemistry.
114. Organic chemistry treats of those substances that are produced under the influence of animal or vegetable life. As these compounds all contain
52 SCIENCE IN FARMING.
carbon, this division of chemistry is frequently called the Chemistry of the Carbon Compounds.
115. All organic substances are composed from the elements named on page 38 with the exception of sil- icon and aluminum. Silicon is not found in animal substances, and seems to be present in vegetable mat- ter rather as an accident than as an essential element ; and aluminum is not found in any form of organic matter. Besides these thirteen elements, very minute portions of a few others are sometimes found.
116. Isomerism.—A large number of organic sub- stances are found to be composed of the same ele- ments, combined in the same proportion. Thus starch and cellulose, though quite unlike, are composed of the same elements combined in the same proportions. Such substances are said to be isomeric, and this par- ticular property can only be accounted for on the supposition of a different arrangement of atoms.
117. Organic substances are divided into nitrogen- ous and non-nitrogenous. The non-nitrogenous com- prise the
Carbohydrates, or amyloids ;
The pectose group 5
Fats;
Vegetable acids.
The nitrogenous comprise the
Albuminoids ;
Amides;
Alkaloids.
118. Carbohydrates are so called because they all contain hydrogen and oxygen in the proportion to form water. Many of them are isomeric. Most of them can be changed from one form to another, either —when isomeric, by a re-arrangement of their atoms,
CHEMISTRY. 53
or when not isomeric, by the addition or subtraction of the elements of water.
119. Cellulose. C,.H.,O,,, forms the solid sub- stance of most plants. It is not soluble in water but dissolves in weak acids. As the plant becomes older, another substance is deposited with the cellulose, called lignose, the exact chemical composition of which has not been ascertained, but which probably contains a larger proportion of carbon than cellulose. It is harder and less readily dissolved.
120. Starch. O,H,,0;.* This is contained in nearly all plants. It is insoluble in water, but read- ily changed into soluble substances, and hence is easily digested. Inulin is a modified form of starch found in some parts of plants. It is more readily soluble than starch. Dextrine has the same composi- tion as starch and inulin, but is readily soluble. Starch is converted into dextrine by the application of heat.
121. Gums are a class of substances found in most plants. They are similar to starch in composition and general properties, but are mostly soluble.
122. Sugars. There are quite a number of vege- table substances possessing the general characters of sugar, and differing but little in composition. The most important are: cane sugar (sacharose) O,,H,,. O,,; fruit sugar (levulose) C,H,,0O,, and grape sugar (glucose) C,H,,O,.+ Cane sugar is found in
*The exact formula for these organic substances is not in all cases fully determined. Some authorities give starch as C12 Hyo0;9. It will be observed that the proportions of the ele- ments are the same in either case. There is no question as to the percentage composition of these substances.
tStrictly speaking, grape sugar is called dextrose, and the term glucose includes both leevulose and dextrose, but in prac- tice the term glucose is principally used to describe dextrose artificially produced.
54 b SCIENCE'IN FARMING.
the juice of the sugar cane, in the sugar beet, and in many other plants. Fruit sugar is as sweet as cane sugar, but differs from it in that it does not granulate. It exists in honey and in many fruits. Grape sugar (glucose) has the same composition as fruit sugar, but differs fromitin being only one-third as sweet. It can be granulated.
Grape sugar differs in composition from starch only by the elements of a molecule of water. If we take
aA MIOIBCHIE Ol Sharebee). P21 Senna ee aes Cg Hio O5 Add P molecule water .o ah! bat ee 2 O1 We have 1 molecule glucose.............. Cg Hie O¢
As the proportionate weights of the molecules of starch and water are 162 and 18, it follows that if we could take 162 lbs. starch and 18 lbs. water and cause them to unite, we should have 180 lbs. glucose.
By boiling starch or cellulose with water and an acid, it is caused to combine with the water, produc- ing glucose. The acid does not enter into the combi- nation, and at the close of the process remains un- changed in quantity and quality. The combination of the starch and water is effected by the presence of the acid, only. ow some substances thus induce changes in others by their presence is not understood. The property is called catalysis.
Glucose is now made on a great scale, and used for adulteration of sugars and syrups and the manufac- ture of candies and alcohol. Starch, sulphuric acid and water are mixed in the proportions of 1,000 Ibs. starch, 21 Ibs. acid and 150 gallons water. The mix- ture is boiled until the starch has been converted into
*When one atom of an element is intended, it is not usual to place the figure 1 after the symbol, as that stands for one atom. We do so in this case to make the addition more clear.
CHEMISTRY. 55
glucose. Chalk is then added, which combines with the acid, forming sulphate of lime or gypsum, which is separated by settling and straining.
When pure, glucose is not unwholesome, but it is often carelessly made, and contaminated with the sul- phuric acid and chalk used in its manufacture.
123. The Pectose Group.—These comprise a large number of substances that are found in plants and especially fruits. They are called pectin, pectose, pectic acid, etc. Their exact chemical composition has not been definitely determined, but they are not true carbohydrates, as the oxygen they contain bears a larger proportion to the hydrogen than it does in water. This group of substances forms the vegetable jellies — which differ from the animal jellies in not containing nitrogen.
124. Vegetable Acids.—These are a very numerous class of substances, and differ from carbohydrates in containing a larger amount of oxygen. In analyses of foods, both the pectose group and the vegetable acids are frequently included in the estimate of the soluble carbohydrates.
125. Fats.—The various oily, fatty and waxy sub- stances found in organic matter are divided into two classes: “volatile” oils, such as oil of peppermint, which give the fragrance to plant and flower, and which will evaporate like water; and “ fixed” oils, which will not evaporate, but leave a greasespot. The latter class are the only ones we need to consider in this work.
Animal and vegetable fats are of the same gen- eral character, and consist principally of mixtures in varying proportions of three fatty principles: stearin —contained largely in tallow and the firmer fats; pal-
56 SCIENCE IN FARMING.
mitin, contained in palm oil, butter, beeswax, etc., and olein, which forms the liquid substance in fats and oils. The striking difference between fats and carbohydrates is the much larger proportion of carbon and hydrogen, and the much smaller proportion of oxygen contained in the fats. This is illustrated in the following table, giving the amount of each ele- ment contained in 10,000 parts of starch, pectin and olein:
Starch Pectin Olein Carbon 4,444 4,067 7,740 Hydrogen 617 508 1,180 Oxygen 4,939 5,425 1,080 10,000 10,000 10,000
It will be remembered that starch fairly represents the carbohydrates, pectin the vegetable jellies, and olein the fats and oils.
126. Albuminoids.—This term is applied to a large number of important substances, including all nitro- genous organic compounds except the amides and alkaloids. Most,if not all of them contain a small quantity of sulphur. Animal and vegetable albumin- oids differ but little in composition. Their exact chemical formula has not been positively determined, but their composition, in 10,000 parts, is about as fol- lows:
CaP POW 3) STR GC Ooi. ie Ga Rr anew nek ne 5,350 Eiydrogen toc so higud re tanh Meee Rae eee 02:0, 5,5) TURE Ng IRE WARREN LS bean N | pao, CURT. 2,240 Nitrogen ts (9) FR Ce Need otc ele AMON, ON ce i ae alan 1,550 ULIMIT 6 Ei Te Re eee ae 160 10,000
By comparison with the table in paragraph 125, it will be seen that they contain a larger proportion of carbon and hydrogen than the carbohydrates and less
CHEMISTRY. 57
oxygen, holding an intermediate position between them and fats.
127. Animal albumin is found nearly pure in the white of an egg. In its natural state itis soluble; but heat, alcohol or acids change it into an insoluble form, or “coagulate” it. This is the change that takes place in cooking an egg. Musculine constitutes the substance of the muscles. Fibrine forms the “clot” in blood. Gelatine is obtained from the skin and bones of animals by the application of hot water. It is commonly seen in glue, and the finer and purer forms are sold as gelatine, isinglass, etc. Gluten is contained in wheat and most grains. It is not a sim- ple albuminoid, but a mixture of several. Keratin is the general name applied to the substances of which horn, hair and wool are formed. Animal casein is found in milk, and forms the substance of cheese. Vegetable casein, which closely resembles it, is found in peas, beans and other leguminous plants.
128. Amides.—These vegetable nitrogenous com- pounds are not well understood. They exist princi- pally in roots and immature plants. In the plant they are convertible into albuminoids, but animals have not the power to effect this transformation.
129. Alkaloids are a class of nitrogenous vegetable substances that exist in the plant in but small quan- tities. Tobacco owes its effects to an alkaloid called nicotine; opium to an alkaloid called morphine; tea and coffee derive their stimulating effects from an al- kaloid called theine, or caffeine. These substances, | though of much general interest, are of little practical importance to the farmer.
130. Transformation of Organic Substances.—The gen- eral similarity of organic substances renders their
58 SCIENCE IN FARMING.
change from one form into another very simple. In the natural laboratories of the plant and animal this is constantly being done. Carbohydrates are changed into .each other, either by a re-arrangement ot their atoms, or by the addition or removal of the elements of water. By the removal of oxygen, carbo- — hydrates are converted into fats, and fats again by the addition of oxygen, are changed back into carbo- hydrates. Out of carbohydrates and nitrates the plant manufactures albuminoids, and the animal can remove the nitrogen and part of the oxygen from the albuminoid and produce fat. These transformations will be more fully considered in the chapters on Plant Growth and Animal Life.
§ 8. Combustion and Decay.
181. The rapid union of any substance with the oxygen of the air, producing light and heat, is called combustion. In common language, it is said the sub- stance burns. The light and heat are produced by the union of the atoms of oxygen with the atoms of the substance, the force that had before been keeping them apart being converted into heat. Substances that will burn are called combustible; those that will not are called incombustible.
When a carbohydrate such as cellulose burns, the hydrogen and oxygen being in the proportions to form water, pass off as watery vapor, while the carbon combines with oxygen from the air, forming carbonic dioxide. As there are 12 atoms of carbon in a mol- ecule of cellulose, and as one atom of carbon unites with two atoms of oxygen in forming carbonic dioxide, it follows that in the combustion of a molecule of cellu- lose it unites with 24 atoms of oxygen from the air.
CHEMISTRY. 59
The process and its results may be thus shown:
Cellulose Oxygen Result. 12 12(CO, ) Hag Dig HOCH, 3}
10 The student will quickly see that there are the same number of atoms of each element on each side of the brace. The proportions by weight would be
1 molecule cellulose, weighing....................... 324 24 atoms oxygen, weighing 16 each ................... 384 EIT POL UTI oo eicce Cts wanlde x io 5 ba Se etks ek a hee 708 Resulting in 12 molecules carbonic dioxide, weighing 44 each...... 528 iomolecuies water, US each ov oe le cee as 180 Pie DG URMIEING Le So ee ay as Ss Oe ee ees tee ESS 708
That is, when 324 parts of cellulose are burned, there is a combination of 144 parts.of carbon with 384 parts of oxygen; or, when 1,000 Ibs. of cellulose are burned, there is a union of 444 lbs. carbon with 1,269 Ibs. oxygen, making 1,713 lbs. of the two elements.
When fat is burned, the proportions are somewhat different. Instead of the hydrogen and oxygen in the fat being in the proportion to form water, there is a great excess of hydrogen, so that not only does a thousand lbs. of fat contain more carbon than a thou- sand lbs. of cellulose, but when it burns, a large part of the hydrogen it contains also unites with oxygen from theair. In burning 1,000 lbs. olein, there would be a union of
AE Oy PN NTIS ht Pic Oe Solr ct a eB 771 Ibs. ae E a tI TeV CEES. Co hh Ne web ei SBE 105 lbs. MTR CeRIVAE TDS Sr8 el chy dao ak emu tao e 6 ea oe 2,929 Ibs.
Total elements.wmiting. 0. oes ee 3,805 Ibs.
So that in the combustion of 1,000 lbs. of oil, the weight of the elements that enter into combination
60 SCIENCE IN_FARMING.
is more than twice as great as in the combustion of 1,000 lbs. of cellulose. Hence the much greater amount of heat produced.
132. Decay.— When organic matters are exposed to warmth, air and moisture, the same chemical changes that take place rapidly in combustion, ‘occur slowly, the result being the same in the end. This process of decay is called by chemists “ eremacausis,” which means slow combustion. During decay heat is pro- duced, as in combustion, but being developed much more slowly, is less noticeable. The products of the decay of non-nitrogenous organic matter are car- bonic dioxide and water. If the substance contains nitrogen, either nitric acid or ammonia will also be produced.
The chemistry of respiration will be explained in the chapter on Animal Life.
CHALE Bye.) No. SCIENCE IN AIR.
§ 1. Its Composition and Characteristics.
183. Composition—The atmosphere is a mixture of oxygen and nitrogen, with a variable quantity of watery vapor, and a small amount of carbonic diox- ide. Its average composition, by weight, in 100,000 parts is as follows:
TVET 210" OS RE en ee ae 78,492 ET re ae ee en ri ek ya howe oes 20,627 (UE Sia SS gh OR ae ed Pe ee ea ee Sat 840 1 CHATS TGs 3 (0S 4]
100,000
This composition is commonly expressed as four parts nitrogen and one of oxygen.
In addition to these substances the atmosphere al- ways contains a small amount of ammonia, dust, and other impurities. The proportions in which these exist are so minute that although their presence can be detected, it is extremely difficult to estimate the
amount. 184. The proportion of oxygen and nitrogen in the
air in the open country never varies. In aclose room where many persons are gathered, or in the crowded streets of large cities, the proportion of oxygen may be slightly reduced. The proportion of carbonic diox- ide is also nearly uniform except in places where from local influences this gas is produced more rapid-
62 SCIENCE IN FARMING.
ly than it can be diffused. The proportion of watery vapor varies greatly. It may be said therefore, that with the exception of water, the composition of the great bulk of the atmosphere is the same at all places and all seasons.
The different gases of which the atmosphere is com- posed are simply mixed together, and are not in chemical combination (57).
185. Diffusion of Gases.—If a jar containing hydro- gen 1s placed above one containing carbonic dioxide, and the two are connected by a small tube, the car- bonic dioxide gradually rises through the tube and diffuses itself through the hydrogen, which at the same time descends diffusing itself through the car- . bonie dioxide, and although the latter gas is twenty times as heavy as the hydrogen this process will con- tinue—the heavy gas ascending and the light one de- scending, until both jars contain a mixture of the two gases in exactly the same proportion. Whenever two gases are mixed, in any proportion, they will diffuse through each other until in time the composition of all parts of the mixture is the same. If the specific eravity* of one of the gases composing the mixture is
*Specific gravity is the proportionate weight of a substance —that is the relation that the weight of a given bulk of one substance bears to the weight of an equal bulk of some other substance taken as a standard. Thus a pint of oil weighs less than a pint of water, and so we say that the specific gravity of oil is less than that of water. A cubic foot of oxygen weighs more than a cubic foot of nitrogen, and we say that its specific gravity is greater. In practice, solids and liquids are com- pared with water as a standard, and gases with air. Thus the specific gravity of lead is 11.44, by which is meant that a given bulk of lead weighs eleven and forty-four one-hundredths times as much as an equal bulk of water. The specific gravity of hydrogen is .069, by which is meant that a given bulk of hydro- gen weighs sixty-nine one-thousandths as much as an equal
¢
bulk of air,
SCIENCE IN AIR. 63
greater than the other, more time will be required to effect the diffusion, but it will be as thoroughly ef- fected. When different gases have thus been mixed, they do not again separate, however great may be the difference in specific gravity. This is called the Law of Diffusion of gases.
It is this law that secures the uniformity of com- position of the atmosphere. Although the specific gravity of oxygen is greater than that of nitrogen, yet through the working of this law, the lower portions of the atmosphere contain no more oxygen than the upper portions. Although the specific grav- ity of carbonic dioxide is much greater than that of the other constituents of the atmosphere, yet it never separates, and settles into the low places and valleys, but the air on the highest mountain peaks contains as much as that at the level of the ocean. Owing to this law also, injurious gases poured into the air are soon diffused through the whole bulk of the atmos- phere, and by their great dilution become harmless. If it were not for this, cities would soon become unin- habitable by the accumulation of carbonic dioxide and other injurious gases, and every low place would be filled with poisonous gas.
186. Apparent Exceptions.—Occasionally there is such an accumulation of carbonic dioxide in cellars, dry wells and old pits that persons entering them in- cautiously, lose their lives. In the island of Java there is said to be a piace called the Valley of Poison, containing an accumulation of this gas. The ground is covered with the bones of animals which have been suffocated while passing through. These ex- ceptions are only apparent. In such cases the gas is being produced in the well, pit or valley,
64 SCIENCE IN FARMING.
more rapidly than it can be diffused through the air.
When there is reason to suspect that carbonic diox- ide—or “choke damp,” as it is popularly called, exists in dangerous quantities, a lighted candle should be lowered into it. If the gas is present in sufficient quantity to be dangerous the candle will be extin- guished. The best method of removing this gas from pits and cellars is by the use of quicklime. One hundred pounds of quicklime will absorb about 675 cubic feet of the gas.
The air near a large city contains a larger propor- tion of ammonia than that in the country, but this also is owing to the fact that the ammonia is produced in the city more rapidly than it can be spread through the surrounding atmosphere by diffusion. The winds assist in securing the uniform diffusion through the atmosphere of gases developed in special localities.
§ 2. Importance of Each Constituent.
No estimate can be made of the comparative value of the different constituents of the atmosphere, as each one is essential.
137. Oxygen sustains life and combustion. It is essential to germination. It unites with organic mat- ter in the soil, giving rise to new compounds that can be used as food by plants. It combines with impuri- ties and poisonous gases in the atmosphere, changing them into harmless forms. It acts upon the rocks and rocky particles of the soil and reduces them to such a condition that plants can use them. It is the great purifier and disinfectant, as it converts dan- gerous organic compounds into harmless inorganic ones. Without oxygen neither plant nor animal could live; and the action of oxygen on the soil is essential to maintain its fertility.
SCIENCE IN AIR. 65
188. The nitrogen of the air serves to dilute the oxygen, and prevent its too energetic action. Being itself perfectly harmless, and in many respects inert, it is excellently adapted for this purpose. Although it is essential to plant growth, the plant has no power to use the free nitrogen of the air; it must be in com- bination with some other element. before it can be ap- propriated by the plant. There is a probability that under certain circumstances the nitrogen of the air contained in the pores of the soil is oxidized and made available for plant food. The free nitrogen of the air is oxidized to a small extent through the influence of: electricity, forming nitric acid, which-combines with the ammonia in the air, forming nitrate of ammonia, which is washed out by the rains. The quantity supplied to the soil in this way varies, but probably the average does not exceed from 6 to 9 lbs. of nitro- gen per acre in ayear,
139. Although the proportion *%of carbonic dioxide in the atmosphere is small, (only one part in twenty- five hundred,) yet the volume of air is so great that the actual amount of this gas is very considerable. It is calculated the air over an acre of ground contains 28 tons of this gas. This is a sufficient quantity to supply the needs of vegetation for many years, even were there no more produced; but the processes of combustion, respiration and decay are constantly pouring this gas into the atmosphere.*
The carbonic dioxide contained in the air supplies all the carbon for the plant. Careful experiments have shown that plants cannot grow and increase in
*The amount of this gas absorbed by the leaves of plants equals that produced, and the balance is thus constantly main- tained.
66 SCIENCE IN FARMING.
weight in an atmosphere containing none of this gas. The constant motion of the winds causes an immense amount of air to touch the leaves of plants, thus enabling them to obtain an abundant supply of car- bon. The farmer, therefore, need have no anxiety about providing carbon or carbonaceous manures to the roots of plants.
140. Water vapor is always present in the air, but the amount varies greatly. The warmer the air the greater amount of water it is able to retain. When the air contains all the water it can hold at that tem- perature, it is said to be saturated. When air that is partly saturated is cooled, a temperature will be reached at which it will be saturated, and any fur- ther decrease of temperature will cause the formation of mist ordew. The temperature at which mist or dew begins to form is called the “dew point.” Suppose the temperature of the air in a room was 70 degrees, ' and it contained enough water to saturate it at 60 de- grees; if then the temperature was reduced to 60 de- grees, any further reduction would result in the form- ation of mist or dew, and 60 would be the dew point. The nearer the air is to saturation the closer will the dew point approach to the temperature of the air. Therefore a high dew point shows that the atmos- phere is nearly saturated. When a pitcher is filled with ice-water in summer, drops of dew soon begin to collect on the outside, and, in popular language the pitcher is said to ‘‘ sweat.”” The expression is incor- rect. The drops of water do not come through the | pores of the pitcher, but the cold surface reduces the temperature of the air touching it below the dew point, and the water contained in the air is condensed on the sides of the gpitcher. On a clear night the
SCIENCE IN AIR. 67
leaves of plants, the surface of the soil and other ob- jects radiate into space the heat they have absorbed from the sun during the day. As soon as they are by this process cooled below the dew point, the mois- ture of the air is condensed on them, and we say the “ dew falls.” Strictly speaking, the dew does not fall, as it collects as readily on the under surface of an ob- ject as on its upper surface. As clouds check this radiation of heat into space (54), we rarely have dew on cloudy nights.
141. As air is warmed, its capacity for water is in- creased, it feels dry, and will absorb water from what- ever it touches, although the actual amount contained is the same as before. This is the reason why the air of a “stove room” is injurious to the lungs, and de- structive to house plants, unless provision is made for increasing the amount of moisture in the air.
The vapor of water in the air is not usually ab- sorbed by the plant, but an increase in the amount present refreshes the plant by checking evaporation from the leaves. The soil absorbs a considerable amount of moisture from the air, and in this way it becomes of use to the plant.
142. The quantity of ammonia in the air is very small. A portion of this is absorbed directly by the leaves of plants, a portion is washed out by the rains, and a portion is absorbed by the soil. The amount of nitrogen brought down by the rains in nitric acid and ammonia has been given (1388). What amount is absorbed by the leaves of plants and by the soil has not yet been determined, and varies so much under different circumstances, that it will be difficult to se- cure an average. The amount absorbed is greatly in- fluenced by the character and condition of the soil.
68 SCIENCE IN FARMING.
The source of ammonia in the air has not been pos- itively ascertained. Some of it is produced by the decomposition of organic matter; some by the burn- ing of coal. There is always a larger amount brought down by rains in the neighborhood of cities than in country districts.
§ 3. Summary.
143. The farmer therefore gets from the air:
Oxygen, to cause the germination of seed, the de- composition of organic matter, and the reduction of the mineral portions of the soil to a form in which they can be used as food for plants.
Nitrogen in the form of ammonia, absorbed by the leaves of plants and by the soil, and brought down by the rains, and in the form of niae acid brought down by the rains. Also, probably, free nitrogen, to be ox- idized in the soil under proper conditions into nitric acid.
Carbon, in the form of carbonic dioxide. The farmer can use the plant for the purpose of collecting carbon from the air and supplying it to the soil, for the improvement of its condition.
CHAPTER VI.
SCIENCE IN SOILS.
§ 1. Origin of Soils.
144, Soil consists of the broken fragments of rock mixed with partially decayed organic matter. The character of the soil, therefore, varies with the kind of rock from which it was produced, the extent of the decomposition it has undergone, and the kind and amount of organic matter that is mixed with the de- composed rock.
145. Rock has been reduced to the condition of soil by various natural agencies. When the conti- nents were under the ocean, the force of the water broke off fragments of rock, and by grinding these to- gether, reduced them to powder. During the ages when glaciers—great rivers of ice—covered much of the earth’s surface, the rocks were ground to powder. After the continents took the form they now have, other agencies continued the work. Water penetrated the crevices of rock, and, freezing, broke and crum- bled it. It also gradually dissolved part of the rock. The air and water together caused the elements in the rock to separate and enter into new combinations. Thus by degrees a soil of inorganic material was
70 SCIENCE IN FARMING.
formed. The rains brought down and added to it ni- tric acid and ammonia from the air, and on this primi- tive soil low orders of plants, at first, began to grow; and as they decayed upon the soil, returned to it all they had gathered from both soil and air. Fresh sup- plies of nitrogen were constantly brought down by the rains, and this the vegetation changed into organic forms and restored to the soil again. Thus, through long ages, the work of preparing the soil went on, and where the hand of man has not interfered, is still going on.
§ 2. Composition and Classification of Soils.
146. Soils are composed of three principal constit- uents—sand, clay, and humus.
Sand is rock reduced to a powder. The composi- tion of each grain is that of the original rock.
Clay is the product of the chemical decomposition of rock. When perfectly pure it is a silicate of alu- mina. It is seldom a pure silicate, however, usually containing potash, soda, magnesia, iron, and other substances.
Humus is partially decayed organic matter. When organic matter reaches a certain stage of decay, it forms a dark colored mass, and decomposition pro- ceeds but slowly. This dark mass is humus.
147. According to the proportion of these three in- gredients, soils are known as sandy, loamy, clayey and peats.
Mixtures of sand and clay are usually classified thus:
SOILS. 71
Name of Per cent of Per cent of Soil. Sand. Clay.
2 CNRS foe Oe Na Agr ma NO Se ee eats oc
Pam ylOAMies tee oy ss DO! oo kee Se eae
USD SIE Aaa ih SES ee 5) peer (Oe aN Cat Dh
Mle OAM ue a Rs RE. ny BAC 75
RMR OL Steed vats 5's hse s = A ree ca 100
Soils that do not exactly agree with any of these, are classed with the one to which they approach most closely. Thus, a soil containing 60 per cent sand and 40 per cent clay, or 60 per cent clay and 40 per cent sand, is called a loam; while one containing 35 per cent clay and 65 per cent sand is called a sandy loam, and one containing 35 per cent sand and 65 per cent clay, is called a clay loam.
In swamps where a rank growth of vegetable mat- ter is produced every year, and decay is checked by excess of water, humus accumulates in great quantity, so that the soil consists almost entirely of partially decayed vegetable matter. Such soils are called peats or swamp muck.
§ 3. Properties of Soils.
The characteristics of soils vary according to their chemical composition and their mechanical condition.
148. Retention of Water.—If a portion of soil is soaked with water and then allowed to drain until no more will flow from it, a considerable amount of capillary water (97) will remain. Soils differ, not only in the amount of water they can retain within their pores, but also in the readiness with which they part with this water by evaporation. In the follow- ing table the first column of figures gives the number of pounds of water retained by 100 lbs. dry soil, and the second column the percentage of this water lost
72 SCIENCE IN FARMING.
by evaporation in a given time, the soils being all spread out and treated alike:
Kind of Water Per cent lost by soil. retained evaporation.
Quartz sands on eee LIE OS RR: 88.4 Clay loam (3.5 yea LOR USS Selene ampeeALE Ts 52
Heavy clay, iG: iti. wane OPE Bie eet tee «ae Me ARE 34.9 OBR sek ee SOR eae oe room 3.5 Ch a ag Te ich Oe 45.7 Garden mould... 6s Sow: BO are eches eye NR Ge eE 24.3 IATA SO), pe raion ie Ame We. | el Ln Reais de aa eran Mie iy Ma een 5 3
It will be seen that while pure sand retained only one-fourth of its weight of water, and lost nearly all of that by evaporation, in the short time (four hours) used in the experiment, humus retained nearly dou- ble its weight, and lost but one-fourth of this by evap- oration in the same time. The retentive power of the garden mould was due to the large amount of hu- mus it contained. |
In general, it may be said that the larger the pro- portion of sand in a soil, the less power it has to retain water, and the more readily it will part by evaporation with what it contains; and the larger the proportion of humus in the soil, the more water it will be able to retain arid the more slowly will it part with it by evaporation.
The coarseness or fineness of the particles of a soil has a great influence on its power to retain water. The finer the particles, the more water it can retain. A very fine sand is greatly superior to a very coarse sand.
149. Absorption of Water from Air.—Soils possess to a greater or less degree the power of absorbing mois- ture from the air. In this, as in the retention of wa- ter, soils differ greatly. The following table shows the number of pounds of water absorbed by 1,000 Ibs.
SOILS. 13
of perfectly dry soil exposed to moist air for 24 hours, the result of one experiment :
Qiirartze samy So 2k 3. @)| Clay loan agar oan 28 Heavy clay i? ie 8S: ab f Loam |. reas lene 30 Garden, mould.:.)........ Bayt ELUMAUs) sie ee een ie 120
Sand, especially coarse sand, has little power of ab- sorbing moisture from the air. Clay has more power, and humus most of all.
The amount of water absorbed from the air depends on the temperature; the higher the temperature the less the absorption. The rapidity with which the ab- sorption takes place depends on the amount of mois- ture in the atmosphere. A given soil at a given tem- perature will absorb the same amount of water from the air, whether it contain a larger or smaller amount of moisture, but a longer time will be required in pro- portion to the dryness of the air.
As aresult of this property, soils—especially those rich in humus— that may become comparatively dry during a hot day, will absorb a considerable amount of water during the night.
150. Capillary Attraction—When a lamp-wick, or any other porous substance, is dipped into a liquid, the liquid will ascend through the pores of the sub- stance, and the force that causes it to ascend is called capillary attraction. The law governing the opera- tions of this force is that the smaller the pores of the substance, the greater hight the liquid will be raised. Soil being a porous substance, possesses the property of capillarity, to a greater or less degree, according to the number and fineness of the pores. In a soil com- posed largely of coarse sand, the pores are large and few, and the upper part of the soil may be quite dry while there may be abundance of water but a short
74. SCIENCE IN FARMING.
distance below the surface. A soil composed of fine particles contains a large number of small pores, and can draw water from considerable depths. Humus possesses this property in the highest degree; coarse sand in the lowest. Soils composed of a mixture of fine sand, clay and humus, often possess it in a very high degree.
151. Retention of Fertilizing Elements.—If the dark colored, offensive liquor from a manure heap is al- lowed to filter through a portion of good soil, the of- fensive and coloring matter will be retained by the soil, and the water that passes through will be free from color and odor. All soils possess this property to some degree, but certain soils possess it to a much greater degree than others.
The effect is partly mechanical. The matters in so- lution adhere to the surface of the particles of the soil, and are thus retained. The more porous the soil, and the greater amount of surface is thus exposed to the liquid, the greater its power in this way.
The effect is also partly chemical. Phosphoric acid, when in solution, unites with lime, alumina, and ferric oxide, forming insoluble compounds. Ammo- nia and potash enter into combination with the silica and alumina of clay soils, forming what are called dou- ble silicates. Calcic carbonate in some cases enables a soil to retain potash and ammonia. Humus has this retentive power in a great degree, acting both chemically and mechanically.
In general, sandy soils have the least power of re- taining fertilizing elements, and the coarser the sand the less its power. Clay and humus have this power to a great degree. The power of clay is increased when it contains ferric oxide, the presence of which
SOILS. 15
can be recognized by the red color it Habart to. the soil.
152. Temperature of the Soil.—The warmth of the soil is derived from the rays of the sun, and is in- fluenced by the character and color of the soil and the amount of water it contains.
Other things being equal, a dark soil absorbs warmth from the sun more rapidly than one of a lighter color (46).
Sandy soil acquires heat more rapidly than a clay, as it is a better conductor (42),and the heat received from the sun is carried down into the soil. Sucha soil, therefore, gains warmth more rapidly in the spring, and is also more aes to “burn out” during a hot season.
A dry soil acquires head more rapidly than a wet one, for the double reason that the specific heat (39) of water is much greater than that of soil, and that so large a portion of the heat received by a wet soil is expended in evaporating the water (34). It requires more than twenty times as much heat to raise the temperature of a wet soil to a point at which seed will germinate as would be required by a dry one. A well drained sandy loam, containing sufficient hu- mus to make it dark in color, is best adapted to secure favorable results in temperature.
153. Absorption of Ammonia.—The soil possesses the property of absorbing and condensing gases within its pores, and when exposed to the air under favorable conditions will absorb ammonia. If substances are present in the soil with which this ammonia can combine, the soil can then take up a further portion from the air. If the soil contains nothing to fix the ammonia, it is liable to be
76 SCIENCE IN FARMING.
again given off in the air and lost. Clay and humus possess to a greater degree than any other substance the property of absorbing and retaining ammonia. A moist soil absorbs more than one that is entirely dry. The rate of absorption depends on the amount of sur- face exposed to the air.
154. Adhesiveness of Soils.— The common terms “light” and “heavy” as applied to soil, have refer- ence to its adhesiveness, or “ stickiness,” and not to its actual weight. A cubic foot of pure sand weighs about 35 lbs. more than a cubic foot of clay, yet a sandy soil is called “light,” and a clay soil “ heavy.” Clay is the most adhesive of all soils, and consequently the most difficult to work. The addition of sand re- duces its adhesiveness. Humus has the same effect.
155. Weight of Soil—The following table gives the weight of the dry soil on an acre taken to the depth of one foot:
7 1010 La are aA cee cata Sages Wht fecha vila Osis, ee 4,792,000 lbs. Dornan ety Apa cies MRE AM a, EAM cet RRL YT Ay SEN 4,182,000 Ibs. Comino plang leaden co ek da aha eee 3,485,000 lbs. PLC ANY, (GLAM come repre aie) ees eee cl siete crete 3,267,000 Ibs. Garden mould 2 UO Vrs ORR Nesey eK 3,049,000 lbs.
Sand is the heaviest and humus the lightest con- stituent of soils, consequently those rich in humus, such as old pastures and rich black lands, weigh less to the acre than sandy or loamy soils.
156. Wastes by Drainage——The water that falls upon the soil and filters through it dissolves a portion of the soluble constituents, and analysis of drainage water shows that it contains nearly every element of fertility contained by the soil through which it has passed, with the exception of phosphoric acid. The amount of most substances removed by drainage is not,: however, sufficient to be of practical importance.
SOILS. 717
Most of the important soil constituents are retained in the manner already explained (151). Nitric acid is the important exception to this rule. Nearly all its salts being soluble it is freely carried away by the drainage water. The Nile pours 1,100 tons of salt- peter into the sea every 24 hours, the result of the drainage of the soil.
About the only means by which the waste of nitrates by drainage can be prevented, is to keep the soil covered with a crop during the season when nitric acid is formed in the soil. The roots of the growing crops take up the nitrates as they are formed, and convert them into insoluble organic compounds.
As will be seen (163), the nitrates are produced most rapidly during the warmer months. Cereal crops, wheat, etc..—leave the soil bare much of this time, and hence are exhaustive because they allow a waste of fertility. When clover is sown with wheat it remains after the latter has been cut, favors nitri- fication and saves the nitrates that are produced, by changing them into organic forms.
§ 4. Chemical Characteristics of Soils.
157. No two soils have exactly the same composi- tion chemically, and it would be difficult even to get two samples of soil from different parts of the same field that would be exactly alike. All chemical anal- yses of soils are therefore approximate, only.
The value of chemical analysis 1 in determining the present fertility of a soil is but small. A soil may contain, as shown by analysis, an abundance of every element of plant food, and yet be unproductive, owing to the plant food being in insoluble combinations. A soil, however, that shows by analysis a large propor- tion of plant food, is usually one that can be made
78 SCIENCE IN FARMING.
productive by proper treatment. The following anal- ysis is of an excellent wheat soil:
SHUG As ae sas ee REA). une os is tea 71.552 Adina ina’ 4s! ls See eee Ree Ree hata ck oc! eles 6.935 OGrTi@ OXI) Meee eee ae nes Bela Ss ela 5.178 Dis ak WME SRNRSRO gy A "eI 0 a EAI 1.229 Nie SIE Aes OR Mn Rem emNeN Bi ele ote srs Res ena ae ee 1.082 IPOi ais aera kine ee ee oc oak Bata dy ea 0.354 OGLE 2 BE, te Sa is MAGE Aah sn chee Gunh cE ak A ale Ae 0.433 POUL DIRT HOI Acetic, Sane gat eo oe AO ee AA ee 0.044 Phosphoric acid ..... AM EDEN CEC yee ly > 0.430 Oise NO VCs OeEET HI 2) enema aR Paar ners, WR eR Aes ART UN fn ta 10.198 WCET Ger soe ea eet os on att Cr teauni hes a cere ee ee 2.684
158. Plant Food.—The greater part of even the most fertile soils is of no value as plant food. Silica, though often found in plants, is not essential to their growth, and alumina does not enter the plant. Of the organic matter in the soil, only a small per cent is of value as plant food. It is necessary that a soil should contain all the elements found in the plant, except carbon, hydrogen and oxygen; but as some of these elements are used by the plant in such minute quantity and are so universally present in the soil, they may in practice be disregarded. The substances usually considered as plant food are:
Nitrogen Potash Phosphoric acid Lime* Sulphuric acid*
An acre of the soil, the analysis of which has just been given, would weigh, taken to the depth of one foot, about 3,500,000 Ibs., and would contain of these substances :
Mitrogen Kprobably) ce oi foneeek ree eee ee eee 8,000 lbs. PHOSPHOTIC BCI «i 544 Woe he ie eee ar eA 15,050 Ibs. BUlomame Beige 207, e ee eee ent eee 1,540 Ibs. POGRSI RRR ah 0. 02) a EE ee aes ee 12,390 lbs. Bis cUe te Seek 2a eR ae PaRRRC L Tae SUE CIN SR i . 43,015 Ibs.
*Lime and sulphuric acid are usually present in sufficient
SOILS. 19
Few soils are as rich in phosphoric acid as the one above given, and many are much richer in sulphuric acid.
159. Exhaustion of Soils—When crops are contin- uously grown and carried away, nothing being re- turned to the soil, the amount of plant food undergoes a steady diminution. A crop of 30 bushels of wheat and the straw will take from the land, of
IND USS 7 Se a a en an CT 45 lbs. Jo 3 SPAR) 8 Oat "C110 aan Se eae 22.7 Ibs. SSL SUSE OG Mit Ae aaa Aa eral Aine ae nen 19.5 Ibs. Potash... .. Pry a Meee eC ne wes chee Sa tule orl ey RO PO MOR: WEIR ibe ss he than ROMAN as Rg Be oudabidhe saree, 10.2 lbs.
If a crop of 30 bushels of wheat to the acre were erown every year, and both grain and straw carried away, nothing being restored to the land, it would ex- haust the soil, the analysis of which has just been given, of these constituents as follows:
ea TOP OM TAs cient) ober Lie at eal HAG ee 177 years. eels DONIC ACL TD. sia ls he Sek ea 766 years. Or saiphurec ache: ime 220s ea Vo 80 years. LIE SCLB ENS) 05 31 G0) a Ge ae as ra ee eee 444 years. Mp aUUMRRPCUN Tiles TMs ind feat, Mer el a None d, Aaja 4,217 years.
Practically it would be impossible to exhaust the soil of these substances, as, before it was exhausted, crops would cease to grow.
160. Rotation —The exhaustion of the soil by a ro- tation of crops, especially where a large portion of the crop is fed on the farm, is much slower. ‘Take, for illustration, a farm of eighty acres. Suppose that the crops grown are Indian corn, wheat, clover and grass; that such a rotation is adopted that twenty acres are each year devoted to eachcrop. Suppose nothing
quantity, and are therfore frequently disregarded in estimating the quality and needs of soils.
80 SCIENCE IN FARMING.
is sold but wheat and animal products. We will esti- mate the annual average crops to be,
Wheat (400:bushels) erences. elec we 24,000 lbs. GES Wh. (sins 5 ca tels eee eR cane ... 48,000 lbs. Clover hay sa Se ee emesis ee oS 100,000 Ibs. ia yi pie ae ie ee eee ter eon Fo sf 80,000 Ibs. Gant CL ATO OPUS VENS) emer eee: Movs eyo cow Meccs 56,000 Ibs. Corn fodder BBA Cas es RG cd hued gehen te i a a 168,000 Ibs.
Calculating that in feeding the straw, hay, corn, and fodder, 10 per cent of the nitrogen, phosphoric acid and potash are taken by the animal, and 90 per cent returned in the manure, the loss of these constit-
uents each year would be: Nitrogen. Phosphoric Acid Potash.
Wheat* 440 lbs. 191 Ibs. 129 lbs. Strawt 23 Ibs. 12 Ibs. 29 Ibs. Clovert 197 lbs. 56 Ibs. 195 lbs. Hayt 124 Ibs. 30 Ibs. 134 lbs. Cornt 93 lbs. 34 Ibs. 20 Ibs. Corn foddert 80 Ibs. 89 lbs. 161 Ibs. Total loss 957 lbs. 412 lbs. 668 lbs.
Dividing these amounts by 80—the number of acres —we get the loss per acre per annum ona farm so con- ducted :
Nitropemy. ae hs Lee eee cee at Comes BL Sc 11.96 lbs. Phosphoricwcidy. 2224 isetieeuy soe. ttc aie 5.15 lbs. I a F< SR ND Sora gS aR Mo ony a ECR MRL 8.35 Ibs.
With this rotation, it would require, to exhaust the soil described in paragraph 158:
Of nitrogen ..... A oeb memgctas oOllns atshaitage haat Bees OSE eae 668 years.
Of phosphoric acids) foe ee eee 2,922 years. Die pOtas:'... Yk tedetehetsmecut oopeivn ep ieae Bree aan 1,484 years.
Under a proper rotation there need therefore be no apprehension of exhausting, or even of materially re- ducing, the amount of plant food in a fertile soil in any ordinary life time. In fact, except by allowing
*Amount contained in entire crop. + One-tenth amount con- tained in entire crop.
SOILS. 81
it to wash away, it would be impossible to exhaust the plant food in any fertile soil in a hundred years.
161. Condition of Plant Food in Soil_The greater part of the plant food in the soil exists in forms of combination that cannot be used by the plant until they have undergone some chemical change. The same causes that prevent the exhaustion of the plant food by drainage, also prevent it from being imme- diately used by acrop. Nitrogen usually exists in in- soluble organic compounds; phosphoric acid in insolu- ble phosphates of lime or iron; potash in combination with silicaand alumina. A soil may contain enough of these constituents to produce 30 bushels of wheat per acre for five hundred years, and yet not contain enough of them in a form the plant can use to pro- duce a single crop of 10 bushels to the acre. Some soils that are called “exhausted” or “run down” contain a great deal more plant food in an acre than others that are called extremely fertile. In the one case the plant food is available, in the other it is not. A large part of the science of farming consists in knowing how to render the plant food in the soil available, and how to secure it with a crop before it is wasted by drainage.
162. Chemical Changes in the Soil.—In order that the plant food in the soil may be rendered available, chemical action must be constantly maintained. The principal agents by which the chemical changes are effected, are the oxygen of the air, and the carbonic dioxide in the water of the soil.
By the action of the carbonic dioxide, the tricalcic phosphate is gradually changed into bicalcic phos- phate, the nature of the change being similar to that fo ed on page 49, carbonic dioxide taking the
82 SCIENCE IN FARMING.
place of sulphuric acid. The same agency also changes the potash into a soluble form.
By the action of the oxygen of the air, the organic matter in the soil is changed into ammonia, water, and carkonic dioxide —and the ammonia is also oxydized producing nitric acid and water.
163. Nitrification —By this is meant the conversion of the nitrogen contained in organic matters and am- monia into nitric acid. It is one of the most impor- tant chemical operations in the soil—as it is in the form of nitric acid—or its compounds with bases— that nitrogen becomes available for the use of a crop. The conditions necessary for nitrification are:
A porous soil. :
The presence of the carbonates of potash, lime or soda in the soil.
Warmth.
Moisture.
Under these conditions and through the influence of a minute fungus plant called bacterium, the nitro- gen of the organic compounds unites with the oxygen of the air, producing nitric acid, which as rapidly as formed combines with the lime, potash or soda pres- ent, forming nitrates.
Nitrification proceeds more rapidly the higher the temperature, and ceases altogether at the freezing point. When the soil contains an excess of water, nitrification ceases, and nitrates are sometimes decom- posed with the escape of free nitrogen.
In order that nitrification may proceed rapidly and keep the growing crop supplied with available nitro- gen, it is necessary that the soil be kept porous so that it presents a large amount of surface to the air,
and that it be moist but not wet. These conditions &
SOILS. 83
are secured by drainage and cultivation. Mulching the ground favors nitrification by keeping the soil in a moist, porous condition. Part of the value of clover and other crops that shade and cover the ground is due to the fact that they thus provide the conditions favorable for nitrification.
§ 5. Mechanical Conditions of Soils.
164. Effects of Division—A cube 1 inch each way, has 6 square inches surface. If it is divided once in each direction, and reduced to 8 cubes, each 4 inch each way, these smaller cubes will have 14 square inches surface—or 12 square inches in all. By the di- vision the total amount of surface has been doubled. If the division is continued until the original cube has been divided into a million cubes, the surface will be increased six hundred times. Thus the smaller the particles of the soil, the greater the amount of surface will be exposed to the air which penetrates it, to the water, and to the roots of plants.
The retention of water and of fertilizing material is due largely to adhesion to the surface of the particles of the soil; hence the smaller these particles the greater the amount of this retention. The absorption of moisture and ammonia from the air is in propor- tion to the surface exposed. The chemical action of air upon the soil is in proportion to the amount of surface exposed. The smaller the particles of soil the smaller and more numerous will be the pores, and hence the greater will be its capillarity.
For all these reasons, the fertility of the soil de- pends greatly on the fineness of its particles, and soil that in its ordinary condition is almost sterile is some- times rendered quite productive by thorough pulver- ization.
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165. Some soils, especially heavy clays, are so com- pact that the air cannot penetrate them, and the roots of plants find difficulty in doing so. Such soils “ bake” into compact masses, and in that condition they are of little value. Itis necessary to mix sand or hu- mus with such soils to make them sufficiently open and porous to admit the air, and to separate their particles so as to prevent “ baking.”
166. Drainage.—Soil may contain water in three conditions: hygroscopic, capillary, and hydrostatic (97). When it contains hydrostatic water the parti- cles of the soil are wet, and the pores between them are filled with water. The water prevents the air from penetrating the soil, and renders it unfit for the growth of agricultural plants,* and the chemical changes nec- cessary to make the plant food in the soil available can not take place.
167. When soil containing hydrostatic water dries, it shrinks and hardens into compact masses. The shrinkage causes the soil to crack, often breaking the roots of plants. This is particularly the case with clay soils. The compact masses thus formed offer great resistance to the roots of plants, and as they can not readily be penetrated by the air, but little mois- ture can be absorbed from it. The cracks caused by the shrinkage are too large to favor capillary attrac- tion, and moisture is not drawn up from below.
Water falling on soil in such a condition is absorbed slowly, and much of it may flow off, leaving the
*The term ‘‘ agricultural plants’’ is used to describe those which are cultivated by the farmer. There are some others which grow under very different circumstances and obtain their food in adifferent manner, such as aquatics, (plants which grow in water), parasites, (those which grow on others), and fungi,
SOILS. 85
ground at the depth of a few inches unmoistened. Therefore an undrained soil, particularly if it bea heavy clay, suffers greatly in a drought.
168. When, by means of ditches or underdrains, the hydrostatic water is removed, the soil remains moist, as the capillary water cannot thus be removed. The roots of plants find sufficient moisture in the par- ticles of the soil, and as the pores are filled with air, this supplies the oxygen necessary for their growth and health.
When a well drained soil becomes dry, it does not harden into compact masses, nor shrink and crack, but remains in a loose and porous condition. During the night the temperature of the soil is reduced by radiation, (44), and moisture is condensed from the air. If the soil is compact and impervious to air, this moisture will be condensed upon the surface only ; but if by drainage it has been left perous, the mois- ture will also be condensed within its pores, often to a considerable depth. Drainage also favors capillary attraction in the soil, thus enabling it to draw water from below. A light rain falling on such a soil is im- mediately absorbed. For these reasons drainage ena- bles the soil to withstand drought.
A loose, porous soil presents to the air many times as much surface as a hard and compact one, thus se- curing a larger absorption of ammonia, and providing conditions favorable for nitrification (163). ° In this way drainage increases the fertility of the soil.
In some parts of Minnesota the soil consists of a deep sandy loam, containing a large amount of hu- mus. The sand is exceedingly fine. This soil seems of almost inexhaustible fertility. It is moist a few inches beneath the surface during the dryest weather,
86 SCIENCE IN FARMING.
and can be worked immediately after the heaviest rain. § 6. Value of Sand, Clay and Humus.
169. Sand.—The value of sand in the soil depends on the kind of rock from which it has been reduced, and the size of its particles. White quartz sand con- tains no plant food, and soils containing it in large quantity are not usually fertile.
To determine the character of the sand, mix a por- tion of the soil with a large amount of water. After allowing time for the sand to settle, pour off the wa- ter, which will contain most of the clay and humus. By repeatedly washing the sand which remains, it may be obtained pure. If it is white, “sharp” and coarse, itis of little value in the soil. Sand from granite or limestone contains a considerable amount of plant food, which, under the influence of air and cultivation, will be slowly given up in avail- able form for the plant. If the portion of soil used in the experiment is first dried and weighed, and the sand that remains also dried and weighed, the propor- tion of sand in the soil will be known.
The mechanical uses of sand in the soil are to make it loose and porous, facilitate drainage and prevent “baking.” Sand alone does not absorb moisture or ammonia from the atmosphere, nor has it the power of retaining plant food. Manures applied to sand have little effect beyond the immediate crop. Sand becomes warm early in the spring, and soils contain- ing it in excess are liable to.“ burn out” in hot wea- ther. When mixed with a due proportion of clay and humus, the advantages of sand are secured without its disadvantages. The finer the sand the more value it is in the soil.
SOILS. 87
170. Clay.—Pure silicate of alumina (146), sup- plies no food to the plant, but clay in the soil usually contains potash, magnesia, lime, and other substances of value. Red clays contain ferric oxide, valuable not only as plant food, but also because it promotes nitrification and aids in retaining nitrates in the soil.
Clay possesses, in a high degree, the properties of absorbing ammonia from the air, and of retaining fer- ‘tilizers. Lime, potash and ammonia combine with it, férming double silicates. Clay thus not only absorbs ammonia from the air, but retains it when absorbed (153). It has also in a considerable degree the power of retaining water, of absorbing moisture from the air, and of capillarity.
Clay soils are called “ retentive.” Manures applied | to them waste but little, and often continue to pro- duce marked effects for years.
The disadvantages of clay are its adhesiveness, mak- ing ita “heavy” soil to work, and its tendency to “bake.” The addition of lime renders it less adhe- sive, the fine particles of calcic carbonate formed in the soil, separating the particles of clay. Burn- ing clay entirely destroys its adhesiveness, and if the burnt clay is mixed with the soil, it has an effect similar to the addition of sand. This plan is sometimes re- sorted to in dealing with very “ stubborn” clay lands.
171. Humus (146).—The proportion of humus in the soil varies from 2 or 3 per cent to as much as 97. To ascertain the per cent of humus, weigh a portion of the soil that has been thoroughly dried in an oven, and heat it to a dull redness, until all the organic matter is consumed. Weigh what remains, and the loss in weight willshow the amount of humus.
Humus contains carbon, hydrogen and oxygen, but
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the plant does not obtain these from this source. It also contains nitrogen in organic combination, which cannot be directly used by the plant, but which is gradually converted into ammonia and nitric acid by the action of the air. The amount of nitrogen con- tained in a soil is usually in proportion to the amount of humus it contains. Humus also contains some phosphoric acid, potash, and other mineral elements _of plant food. 19
Humus has other value in the soil besides supphy- ing plant food. Its dark color makes the soil warmer. It has great power of retaining water and of absorbing moisture and ammonia from the air. Being very porous it possesses capillarity in a greater degree than any other soil constituent. The decomposition of humus in the soil produces carbonic dioxide which, being dissolved in the water of the soil, assists in the decomposition and solution of mineral matters.
Humus overcomes the adhesiveness of clay soils, and remedies the deficiencies of sand.
The addition of lime to humus hastens its decom- position by favoring the conversion of the nitrogen it contains into nitric acid.
§ 7. Practical Application.
172. The soil best adapted for most agricultural purposes is composed of fine sand, clay and humus. No one of these ingredients should be in great excess.
173. Correcting Defects in Soil—Soils may be good in many respects and contain an abundance of most of the elements of plant food, and yet from deficiency of some one constituent, or defective mechanical con- dition, be unproductive. Such soils may often be rendered valuable at moderate expense by proper treatment, which can be determined by a considera-
SOILS. 89
tion of their character and of the principles already given. |
174. A soil may contain an excess of humus and yet be unproductive. The plan to pursue is to secure the decomposition of the humus, and the conversion of the plant food it contains into available forms. This can be accomplished by drainage and thorough cultivation, by which the soil is exposed to the air, and by the addition of lime. Soils of this kind are sometimes “sour” owing to the presence of organic acids produced by the slow decomposition of humus, and which are injurious to plants. Lime combines with these acids forming harmless compounds. The addition of phosphates or potash may sometimes be beneficial.* When phosphates are needed, rock phosphate—which contains no nitrogen—would be suitable, as the soil already contains an abundance of nitrogen which only needs to be rendered available. Green manuring on such a soil would be injurious rather than beneficial.
175. A sandy “leachy” soil may be improved by growing a succession of green crops, rye, buckwheat, sowed corn, clover, etc., and plowing them under. The humus thus furnished will supply those charac- teristics of the soil lacking in the sand. Nitrogenous manures may be used with profit, but they should be applied on the surface and at the season when the plant can make immediate use of them. After a suf-
*Whether phosphate and potash are needed can only be de- termined by experiment. Four portions of the field should be marked off. To one portion phosphate should be applied, to another potash, to the third both, and the fourth should re- ceive no manure. The cultivation, drainage and liming of the four portions should be the same, and the results carefully noted,
90 SCIENCE IN FARMING.
ficient amount of humus has accumulated in the soil, the crops may be fed off and the manure produced returned.
176. A “retentive” clay is often a difficult soil to deal with, but can usually be rendered valuable by proper treatment, and as it has great capacity for retaining manures, those which are applied and not immediately used by the crop will accumulate in the soil. The first treatment indicated is thorough drain- age—which will make the next step—thorough culti- vation, possible. The adhesiveness may be overcome by the use of lime, by plowing under long barn-yard manure, and by green manuring. Nitrogenous manures, such as bone phosphates and guano can be used with advantage—but should not be applied at the same time with the lime, or a waste of nitrogen may be occasioned. After the condition of the clay has been sufficiently improved, the plowing under of green crops may be discontinued.
177. Thus by drainage, cultivation, green manur- ing and the use of lime, the farmer can to a great ex- tent remedy natural deficiencies in the soil. Of the three great soil constituents, humus is the only one over which control can be exercised. By the use of lime and cultivation it can be reduced in quantity when in excess; and by plowing under green crops it can be increased when needed.
CHAPTER VII. SCIENCE IN PLANT GROWTH.
§ 1. Composition of Plants.
178. Water.—The largest constituent of all living plants is water. The following table gives the aver- age percentage of water in various fresh plants:
De RIPON. oP Di Se ah cs Bhs che ah tare Lhe wha ai 72 RI ee i es ea L OAt Tae Penk Teds 79 IMIR Re ee Fd a ST eenaes, ue ee aa oe 81 MRR ea SP Salis 1 neta aid cla acshcaed Sut diseeuted ih ds 90 EMIRATE oy. nc se ce sche oe lee ae een 7D RG Rk Aa as cls. crater Ph Mle Meee, oh LUMA LSE rcs See 82 TERR ORF Sn opcdtichis ht Me Shanta Gada: «chal dch gene « 91 2 gs ER ed ans OR ERS AA ties IEE ieee Pe One Ee 94.5
The per cent of water is not always the same. It is greater in plants grown in a wet season than in those grown inadry one. The ranker the growth of plants the more water they contain, hence the in- creased weight of crop caused by heavy manuring is often chiefly water. In some cases the amount of dry matter contained in a crop grown on a manured soil may be less than that in a crop produced without manure. The following table gives the weight (fresh and dried) of two crops of clover grown on an acre of ground each, one with, and one without manure.
Fresh Clover. Clover Hay.
WPSMUINCE, AOTC (Gs. se sais aes 22,256 lbs. 4,800 lbs. Unmanured acre........,..... 18,815 lbs. 5,190 Ibs.
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It will be seen that while the crop on the manured acre was ranker and weighed more when fresh than that on the unmanured acre, it contained so much more water that the amount of hay was less.
179. Even dried plants and the seeds and grains contain a considerable amount of hygroscopic water (97). The following table gives the per cent of water contained in various plants and grains that are usually considered dry:
Meadow thay C.cwas our aa Oe. ee Oa oe ee 15 Plover Day hee ih MOIR te Raye ra 17 SSEEUW oul Bee a yt eee, me eae AL ce ee 15 Wheat :(erain) 05 Wee va. eo ag ee eee 14 Tngian corn) Conaaen) 62). 2 a5 5 sguis-nactledpspecdslo st ae eae 12 Wheat’ branes. 72020 2) Oe ees Le ce 14
The amount of hygroscopic water varies a little with the temperature and the condition of the atmos- phere.
The term “dry substance” is used to describe all the plant except the water. Thus, fresh meadow grass contains about 28 per cent dry substance; meadow hay 85 per cent; Indian corn 88 per cent, and soon. That is, 100 lbs. meadow grass if dried at a temperature of 212, so as to drive off all the water would weigh 15 lbs.; 100 lbs. Indian corn would weigh after being dried in this manner 88 lbs. As the quantity of water in different plants varies so greatly it is often necessary in making comparisons to con- sider only the dry substance each contains.
180. Ash.—When a plant is burned, part passes off in gas and vapor, but a part remains unconsumed. This is called the ash, and the amount of it varies in different plants, and in the same plants grown under different circumstances. Plants grown on a soil rich in available ash constituents will contain more ash
@ wi
PLANT GROWTH. 93
than the same plants grown on soil in which these substances are deficient. The following table gives the percentage of ash in the dry substance of various plants:
ME RT reg hie ai he 6 e+ oni eya n ageelqa a: 2 NRE ea he ete ee ee Saree ee os ne mayne 3.3 Times Corn. (Pratl) .). MOIS 8) oe ee ee 1.5 LTE SOE Bg 8 ORES RR Rete Pe Paes ee er eS ee Feil Te a re ra lair kes Pinar tnals A ete e ate aes 6.7 eI EOQULS) Shoe eh Lee Se eel a see ee Bea eens 12
That is, if turnips were thoroughly dried at the temperature of 212, and 100 lbs. of this dried turnip burned, 12 lbs., of ash would be left. The following table gives the number of pounds of ash in a ton of various vegetable substances in their natural con- dition:
Name of Substance. Ash in One Ton. PUIMAEGAN Oj Adin sees cba alare Sim aden a! aede lie erode +, 4p 70 lbs. NARS GP IMI ices) have a cab: SSdeinesg ous oo oan ote o Puclia + & hw dl 34 lbs. De MROR CORT CREA) 868.6 ae ie fees 32 lbs, ICEMAN) bridged res Sih 5 POS ARR LEAS «0 Ploih aot 122 lbs. CE UEP ELSE TE ORS Sg Sari ee ace ra Ole Ie oe 106 Ibs. ee eg aoe Sod feed oaete he ahs wes 3 124 Ibs. WNNCG aha We hess ih 3 2 REPL Ak). coheed ie as RG 92 lbs. HENS CC ee 1 a ei aa ean a PUN 40 lbs. RMT OCS tre ee head A ee ee hens hoo tw oe 30 lbs. arm er ee Fy A ih Lae Sas Ad 20 lbs IAN ite ti, ON aS ia oe haha al) yan knee i dn 14 lbs
The ash of plants consists principally of lime, pot- ash, phosphoric acid, sulphuric acid, soda, magnesia and iron. Chlorine is occasionally present, and silica quite frequently (158). Minute portions of other sub- stances are frequently found, but do not seem essen- tial to the plant.
181. Other Substances.—The remainder of the plant is composed of cellulose (119) and other carbohy- drates (117), lignose (119), albuminoids (126), pectose
94 SCIENCE IN FARMING.
substances (123), amides (128), vegetable acids (124), fats (125) and alkaloids (129).
§ 2. Germination.
182. A Seed is composed of two parts—the embryo and the endosperm. The embryo, commonly called the “chit,” is the undeveloped plant. The en- dosperm forms the bulk of the seed, and is the pro- visiun made by Nature for the nourishment of the young plant.
183. Chemistry of Germination.— When aseed is sub- jected to favorable conditions of moisture, air and tem- perature, water and oxygen are absorbed, and certain chemical changes occur. The starch in the endosperm is converted into glucose and other soluble substances; fats, by combination with the elements of water, are changed into soluble carbohydrates; and albuminoids also become soluble. The nutriment in the seed is thus prepared for the use of the plant.
Two stems are now thrown out from the embryo ; one, called the radical, turns downward into the soil, the other, called the plumule, turns upward and seeks the light. The substances in the endosperm that have been rendered soluble, are dissolved by the wa- ter absorbed, and carried through the growing plant, and in the proper places changed into cellulose and other insoluble substances.
This process continues, the young plant being sup- ported by the nutriment stored in the seed, until that is‘exhausted, as it has no power to obtain any other food until the leaves are formed and exposed to the © light. Ifthe nutriment in the parent seed is exhaust- ed before the leaves reach the light, the young plant dies of starvation.
PLANT GROWTH. 95
184, Necessities of Germination.—These are oxygen, water and a proper temperature. The soil performs no part in the work except to furnish the proper con- ditions. Oxygen and water are both needed to effect the chemical changes by which the substances in the seed are rendered soluble, and water is necessary to dissolve them and convey them to the different parts of the growing plant.
Numerous experiments have been made to deter- mine the lowest and highest temperatures at which germination is possible, and that at which it proceeds most rapidly. The following table gives the results with certain seeds:
Lowest Highest Most Rapid Temperature. Temperature. Germination. Wheat and Barley 41 deg. 104 deg. 84 deg. ao ee eee 44.5 “ 102;..** 84 “ Indians corn... ....;.. 7 a {aa os, RIGUECUER eons te Sy FH 0345:
Some other seeds will germinate at much lower temperatures. Itis said that rye will germinate at any temperature above the freezing point.
§ 3. How the Plant Grows.
185. Plant Food.—The plant has no power to create any substance. It can therefore only grow by col- lecting certain elements from the soil and air and forming out of these the various organic compounds. The elements used by the plant are carbon, hydrogen, oxygen, nitrogen, phosphorus, sulphur, calcium, pot- assium, magnesium and iron. Without these ten, no agricultural plant can be formed, and deficiency in one cannot be made up by an over-supply of another. After germination, the plant obtains its food by means of its roots and leaves.
96 SCIENCE IN FARMING.
186. The Roots gather from the soil all those sub- stances which form the ash of the plant, and also ni- trogen, usually in the form of a nitrate. These sub- stances are taken up in solution. The roots have power, however, to attack some substances that are not ordinarily soluble. This is due to the acid sap which they contain, and which dissolves some sub- stances when they are in direct contact with the roots. It is inthis manner that plants obtain phosphoric acid —a substance that rarely exists in the soil in a solu- ble condition. The roots also obtain from the soil the water necessary for the growth of the plant. Solu- ble substances in the soil not essential to the plant, are often taken up by the roots. These are usually deposited in the older tissues, or as a crust upon the stem of the plant, and often serve a useful purpose by hardening the tissues and protecting them from injury. Carbonic dioxide is also taken up by the roots, but the amount is so small that the fact is of scientific interest, only.
187. The Leaves absorb carbonic dioxide from the air. This is taken up by the minute pores of the leaves. These pores are called stomata, and are very numerous. An ordinary apple leaf has about 100,000 to the square inch. The carbonic dioxide is decom- posed in the leaf, the oxygen being given off and the carbon uniting with the elements of water to-form carbohydrates. The decomposition of the carbonic dioxide in the leaf is performed in what are called the chlorophyll cells. These cells contain a green liquid called chlorophyl, and to which the green color of the plant is due.* All green portions of the plant have
*Plants which have no green color cannot obtain carbon from the air. These are chiefly parasites—which obtain their
PLANT GROWTH. 97
the power of decomposing carbonic dioxide, but the work is principally performed by the leaves.
The plant obtains the power by which this decom- position of carbonic dioxide is accomplished, from the sunlight. The process ceases entirely in the darkness.
All green plants are thus during the day-time con- - stantly taking carbonic dioxide from the air and re- turning oxygen.
Albuminoids and amides are formed from the solu- ble carbohydrates in connection with nitrogen and sulphur obtained from nitrates and sulphates in the sap. Fats are produced by the removal of a part of the oxygen and hydrogen of carbohydrates, and vege- table acids by their oxidation.
The leaves absorb from the air a very small amount of ammonia, which is used by the plant in the forma- tion of albuminoids and amides.
188. The soluble carbohydrates and other sub- stances when formed are carried in the sap to every portion of the plant, and its tissues are built up by the conversion of these soluble substances into cellu- lose, lignose, and other insoluble forms. Thus every part of the plant, including the roots, is built from the carbon obtained by the leaves.
189. The plant has the power of rendering soluble substances that have been deposited in one part, con- veying them to another, and changing them into new forms. If a tree is stript of its leaves, it can no longer obtain carbon from the air, but carbohydrates already deposited in other parts of the tree will be taken up by the sap and used for the production of new leaves. If these are removed as rapidly as they are produced,
carbon from the juices of the plants they live upon — or fungi, oe obtain it from decaying organic matter,
98 SCIENCE IN FARMING.
the tree will continue putting forth leaves until the available supply of material is exhausted; when it dies.
During the fall the carbohydrates, albuminoids, phosphoric acid and potash contained in the leaves are Jargely re-absorbed and deposited in the trunk. With the coming of warm weather the sap begins to circulate, these substances are converted into soluble forms and used for the production of new leaves. The sugar in maple sap is produced from the starch stored up the previous fall.
190. Respiration—The plant is continually absorb- ing oxygen through the bark and leaves. This com- bines with carbon in the plant forming carbonic diox- ide, which is thrown off. This process continues both in daylight and darkness, and so closely resembles the respiration of animals that it has been given that name.
During the daytime the amount of carbonic dioxide absorbed is many times greater than that given off; and consequently the process of respiration is not noticeable, but in darkness when the absorption of carbonic dioxide ceases, the effect. of respiration be- comes perceptible. Hence it is sometimes said that plants absorb carbonic dioxide during the day, and give it off during the night. The statement is not scientifically correct as respiration continues at all times, but its effects are hidden, in daylight, by the larger amount of carbonic dioxide absorbed, and of oxygen given off.*
*From the fact that plants give off carbonic dioxide in the night, the theory has been advanced that they are injurious in bed-rooms. The amount of this gas given off is so minute that it could have no appreciable effect: on the air of any ordinary
PLANT GROWTH. 99 § 4. Formation of Seed.
191. The Seed.—As we have seen (182), the seed contains nutritive matter in the most concentrated form, it being Nature’s provision for the nourishment of the young plant until the time when it shall be able to collect food for itself. We therefore find in the seed every element needed for the life and growth of the plant. The composition of seed is more uniform | than that of any other portion of the plant, and they never contain any of the unessential ash constituents sometimes taken up by the roots.
192. Annuals——These are plants which germinate, attain maturity, and produce their seed within a single season of growth. During the early part of the life of an annual, its energies are entirely devoted to the formation and development of the organs of nutri- tion, the leaves and roots. When the flower is put forth this process is checked, and as the formation of the seed progresses, less and less food is gathered from the soil and air, and the energies of the plant are devoted to gathering up the nutritive matter already formed within its tissues, changing them into more concentrated forms and depositing them in the seed. The final work of storing food in the seed is done after the plant has entirely ceased to collect food from without.
Thus as seed formation in an annual progresses, the whole plant undergoes exhaustion, and, if the season is favorable§.this exhaustion is very great. Consequently the straw of a crop is more valuable in a season unfavorable for the maturing of the grain.
room. A growing plant absorbs during daylight a great deal more carbonic dioxide than itggives off in 24 hours.
100 SCIENCE IN FARMING.
The extent to which this exhaustion of the plant is carried is shown in the following tables giving the percentage of soluble carbohydrates,* albuminoids, and crude fibret+ in the dry substance of various plants, before and after the formation of seed:
RED CLOVER. Cutin Bloom. Cut When Ripe. 4
Soluble carbohydrates......... Das he eee ,. 24. Alpummoidgy ecw oon es bese o AGO goaan Aivanes 11.3 Crmgdemipre : ees ons ton soe Me 1 Ips San Oe ag 57.6 RYE FODDER. Cut in Bloom. Ripe Straw.
Soluble carbohydrates......... HauOsy fa th eens 31.5 Alpumuinoids 70 sees ie coe a 12D cs eke ee 1.8 Crude HbR ke vice nh Sarre 26.9 tie eee 63.0
INDIAN CORN FODDER.
Cutin August. Cut after Grain has ripened.
Soluble carbohydrates......... aa Ney finn eieg re 45.3 Albaminoigds yen, -.c cee ee oe 6 PRM allt 3.5 Crude appre 4.5.4 2500 2. ae a 2D. A io eee SER ee 46.5
The decrease in proportion of the nutritive sub- stances—especially albuminoids, is very noticeable in each case.
It must. be remembered that these tables give the percentage composition of the dry substance only, the purpose being to illustrate the exhaustion of the plant in the formation of seed. They cannot be used to compare the value of a ton of green rye fodder with a ton of rye straw, on account of the different amount of water. This part of the subject will be considered elswhere.
193. Biennials.— These are plants which grow
*The term ‘‘soluble carbohydrates” is frequently used in analyses of foods to represent not only the true carbohydrates, but also the pectose substances (228).
+Crude fibre consists of cellulose and lignose in such forms. that they cannot readily be dissolved.
PLANT GROWTH. 101
through one season, producing only leaves and roots, and the next season throw up a flower stalk and pro- duce seed. Beets and cabbages are biennials. In these plants the first year’s growth is devoted to col- lecting nutritive matters from the soil and air and storing them, either in a fleshy root, as in the beet, parsnip and carrot, or in a leafy head, as in the cab- bage. Inthe second season the flower stalk is thrown up and seed produced from the material that had been stored up during the first season.*
194. The tuber of the potato and the bulb of the onion are similar storehouses of food. Men and ani- mals take advantage of these characteristics of vege- table life, and find much of the best and most concen- trated food in the seeds of annuals, and the roots of biennials—gathered at the close of the first season— or if they use the whole plant do so before the pro- duction of seed begins.
§ 5. Summary and Practical Application.
195. Germination.—The necessities of germination are water, air, and a suitable temperature. When the pores of the soil are filled with water, germination is greatly retarded, as the water excludes the air. Too deep planting retards germination for the same rea- son. As moisture is essential, it is necessary that the soil should be well pulverized, otherwise the seed may fall into cavities between the lumps of soil and be unable to obtain sufficient moisture; or if damp- ness of the weather at the time of sowing the seed en- ables it to germinate, a few dry days following may
_ *A plant cannot take up by its roots and use organic matter in the soil, but it can take organic matter from one part of its own structure and use it for building up some other portion.
v
102 SCIENCE IN FARMING.
cause the young plant to perish before its roots can penetrate the soil far enough to obtain a supply of moisture. As warmth is necessary, seed sown before the ground has become sufficiently warm is liable to rot instead of germinating. Indian corn, especially, requires a considerable degree of warmth, and a “* bad stand ” is often the result of planting in cold ground.
As the parent seed is the only source from which the young plant candraw nourishment until its leaves reach the light, when seeds are too deeply planted, the young plant may exhaust this nutriment and die from starvation before its leaves reach the light. Hence, also, if the leaves are torn from a young plant just as germination is completed, it dies, being de- prived of means of obtaining food from soil and air, and having no source of supply within itself. If the plant is allowed to grow for atime after germination, a supply of material is laid up within its own tissues which can be used for the production of new leaves. A practical knowledge among farmers of the working of this principle has given rise to the expression that “the best time to kill weeds is before they come up,” by which is meant just as the proone of germination is completed.
196. Plant Food—As the plant cannot use the ni- trogen contained in organic matter in the soil until it has been oxydized into nitric acid, it is necessary to expose the soil thoroughly to the action of the air, in order to secure a sufficiency of available plant food. The nitrogen in urea being available for the use of the plant without first being oxydized, urine acts very rapidly as a fertilizer. As, when one element of plant food is deficient, the plant is incapable of using other food, however abundant it may be, it is necessary to
»
PLANT GROWTH. 108
see that all the elements of plant food needed are con- tained in the soil and in an available condition. As the carbon in the plant is obtained wholly from the air, carbonaceous matters in manures are without value as plant food.
197. The Growing Plant.—As the whole plant, in- cluding the roots, is built up from carbon obtained by the leaves, no: growth can be made after the leaves have been removed, and hence, if insects are allowed to continually destroy the leaves of trees, the trees themseives will ultimately die. Hence, also, if weeds are constantly cut down and not permitted to put forth leaves, the roots will ultimately perish. In order to kill a weed in this way, however, the leaves must be removed as rapidly as produced, for if they are allowed to remain even for a short time, they will lay up another store of surplus material.
CHAPTER VII. SCIENCE IN ANIMAL LIFE.
§ 1. Composition of the Animal.
198. General Composition—Animal substances are composed of the same ten elements as vegetables (185) with cholorine and sodium in addition. These two last elements form in combination common table salt (106), and though not essential to plant life, are usu- ally present in vegetable substances.
199. Organic Compounds.—These are principally Albumnoids Gelatinoids, Keratin (127) and fats. Car- bohydrates do not exist in the animal body except in the form of partially consumed food.
200. Ash.—The ash consituents are principally found in the bones, of which about 55 per cent. is tricalcic phosphate. Iron and potash are also found in all parts of the system.
201. Water.—As in the plant, the larger part of the living animal is water. The following table shows the average composition of a half fat ox, weighing 1,000 Ibs. exclusive of stomach and intestines:
VERE ic cae ee aS os ke alee ale Re ia Le) 2 Gahan lee 560 Nitrogsenbus matter i000. 25a eae Sek kt eae eee 181
2) SOME HeLa ESA PRR EPUB Wait ace Ca a Ses WE egies fy on, 208 f=) sR eo eRe reper eS te Mrgme ay Na 2 51
ANIMAL LIFE. 105
202. Comparison with Vegetable Matter.—The ani- mal contains less carbon, hydrogen, and oxygen than the plant and more nitrogen, phosphoric acid and lime. The following table shows the number of pounds of these contained in 1,000 lbs. of a fat ox, (exclusive of stomach and intestines) and in an equal weight of fresh clover in bloom:
Fat Ox. Fresh Clover. PTD ay fe Sit Screen) oo 5y0 6 holm os 23.18 5.10 PBOSPNOMIC ACIG. os. ce lio 16.52 1.40 ecu, SAO) le ORR SI ea Ae aR 19.20 4.80
§ 2. Animal Nutrition.
203. We have seen that the food of plants consists of gasses, mineral salts, and water, out of which it forms all of its various organic compounds. The power by which these transformations are accom- plished is obtained from a source outside of the plant —the light of the sun.
The animal is unable to construct organic matter out of inorganic, nor can it obtain power for carrying on the functions of life, from any outward source. It must therefore find in its food, in forms that will re- quire but little change, the materials it needs, for growth; and, also the source of animal heat and en- ergy. The plant is therefore the machine by which inorganic matter is prepared for the use of the animal and the medium through which the energy derived from the light and heat of the sun 1s made available for the purposes of animal life.
204. Digestion—The food of animals consists of carbohydrates, albuminoids, fat and mineral salts con- tained in the plant. These are fitted for animal nu- trition by the process of digestion. Some of the car- bohydrates, such as sugar require but little change.
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Others, such as starch and cellulose must be converted into glucose. This change is begun by the action of the saliva, and is completed in the intestines. The albuminoids are rendered soluble by the action of the gastric Juice secreted by the stomach, and also by the pancreatic juice. The digestion of fats is accomplished by the bile and pancreatic juice.
205. Assimilation— After the food has been ren- dered soluble, or digested, it is absorbed by the mi- nute blood vessels lining the intestines and by vessels called the lacteals, and carried by the blood to every part of the body. Each part takes from the blood the needed material for its own growth or repair, and changes it into substance like itself. This is called assimilation. Thus all parts of the body are nour- ished by the blood. How the tissues make the selec- tion from the blood, of the particular materials they need, is not understood. |
206. Waste of the Body.—The tissues of the body are continually undergoing oxidation anddecay. ‘The waste matter thus produced is taken up by the blood, and removed from the system through the excretory organs. This waste is repaired by the blood which serves both to bring the new material and remove that which is worn out.
207. Respiration——By the actionof the heart, the blood is forced through the lungs. Owing to the pe- culiar structure of these organs, it is here very thor- oughly exposed to the air, and absorbs oxygen, which gives it a bright scarlet color. In the circula- tion of the blood the oxygen thus absorbed, combines with the carbon of the food, the process being similar to combustion (131). The carbonic dioxide formed by this process is given off by the lungs. When ear-
ANIMAL LIFE. 107
bohydrates suffer oxidation in the blood the products are carbonic dioxide and water. When albuminoids or amides are oxidized the nitrogen is separated in the form of urea (CON,H,) a substance containing 46.67 per cent of nitrogen, and which is removed from the blood by the kidneys.
208. Excretion is the process by which waste or useless material is removed from the body. The prin- cipal organs of excretion are the lungs, kidneys and skin. Carbonic dioxide, water and small portions of waste organic matter are thrown of by the lungs, and skin. The kidney removes the urea produced by the oxidation of nitrogenous substances, and the mineral salts. The solid excrement is composed of the undi- gested portions of the food, with a small amount of bile, and secretions of the intestines.
§ 3. Uses of Food in the Body.
209. The principal uses of food are:
1. To furnish material which can be burned in the body for the production of heat and energy.
2. To supply material for growth.
3. To repair the waste of the body (206).
4. To produce fat.
5. The production of milk.
210. In the construction of fat, flesh, or milk, the animal must find in the food all the elements which the substances to be formed will contain. From a carbohydrate it can produce fat, because they contain the same elements, the difference being only in the proportions in which they are combined. It can also produce fat from an albuminoid, by the removal of the nitrogen, but it cannot produce an albuminoid from
108 SCIENCE IN FARMING.
fat or a carbohydrate, as neither of these substances contains nitrogen, which is an essential element in the albuminoid.
Albuminoids are therefore capable of meeting all the requirements of the body, and can support life without any other food. Fats and carbohydrates can be used for the production of fat, and to furnish car- bon for combustion in the blood.
The respective values of these different classes of foods will be considered in the next chapter.
211. Source of Animal Heat and Energy.—We have seen (37) that in the locomotive, energy that had been obtained from the sun by plants long ages ago, is set free, by the combustion in the fire-box, of the carbon of the coal, and that this energy is applied to useful work by the machinery of the engine. In the animal the energy derived from the sun by agricultural plants is set free by the combustion, in the blood, of the car- bon of the food, and the muscles and organs of the body are the machinery by which this energy is ap- plied to useful work. Part of it is expended in main- taining the heat of the body, part in carrying on the processes of respiration, digestion, circulation, etc., and part may be used by the animal in physical exer- cise or useful work. The combustion of a given amount of carbon from the food, will produce a given amount of energy and no more. If more of this en- ergy is used for maintaining the heat of the body, less can be used in the performance of work, and if an in- creased amount of heat and work is needed, there must be an increased consumption of food.
§ 4. Disposition Made of the Food. 212. Heat and Energy.—By far the greater portion
ANIMAL LIFE. 109
of the food consumed by the animal is used in the production of heat and energy. The heat of the body must be maintained, and even when the animal is at rest a large amount of energy is used in the processes of digestion, respiration, circulation, etc. Ina fatten- ing animal, the amount of food used in this manner is from three to ten times as great as the amount used in the production of increase. In animals that are not growing or laying on fat, the proportion of food used for the production of heat and energy is still greater. If the food contains a due proportion of car- bohydrates and fat, these will be used for this purpose rather than the albuminoids.
218. Growth and Repair.—The albuminoids in the food are used for producing new tissues, and also for repairing the necessary waste. The amount required for this latter purpose is but small. An ox weighing 1,000 lbs. will require only five- or six-tenths ofa pound of albuminoids per day to repair the waste of tissue. Albuminoids ‘consumed in excess of the amount required for growth and waste, are either burned for production of heat and energy, or convert- ed into fat. In either case the nitrogen is separated in the form of urea.
214. Production of Fat—When more food is con- sumed and digested by the animal than is required for growth, the repair of waste, and production of heat. and energy, the surplus will be converted into fat, and stored up to meet future demands of the system. The production of fat is in fact the one method by which the animal can dispose of food consumed in ex- cess of immediate needs. |
215. Milk—When an animal is giving milk, a large amount of the food consumed is used in its pro-
110 SCIENCE IN FARMING.
duction. Fats and carbohydrates are used in form- ing the fat and sugar, and albuminoids for the casein. A large amount of mineral salts are also used in milk production.
216. The mineral salts obtained in the food are largely used in the production of the bones. Those not used are removed by the kindeys.
217. Undigested Food.—The animal never digests all the food it consumes. The amount left undigested varies with the kind of food and the animal: It is seldom less than five, and sometimes as much as sixty per cent 6f the dry matter of the food consumed. This undigested food passes off in the solid excrement.
§ 5. Effects of Insufficient Food.
218. Insufficient Albuminoids— When the albumin- oids supplied to an animal in its food are but just sufficient to repair the waste of tissue, muscular growth will necessarily cease. If the amount of albuminoids in the food is insufficient to repair the waste, the ani- mal will gradually shrink in weight, and finally die of starvation, even though abundantly supplied with non- nitrogenous food constituents. Instances are on re- cord of children who have died from starvation while being fed on a purely farrinaceous (starchy) diet. In- jury to children raised by hand, from insufficient al- buminoids in their diet is more common than is usu- ally;Known. ?
219. Insufficient Non--Nitrogenous Constituents. — When carbohydrates and fat in the food are insuffici- ent to meet the demands for the production of heat and energy, the albuminoids will be burned for this pur- pose, even though growth is stopped and the wastes of the body go unrepaired. In this manner, deficiency
ANIMAL LIFE. 111
of non-nitrogenous matter in the food may cause loss of muscular weight, although these substances are not capable of conversion into muscle. Owing to the same principle, an increase of non-nitrogenous matter in food may cause an increase of muscular develop- ment, provided the food already contains a due pro- portion of albuminoids. The increase in such a case is not due to the conversion of the non-nitrogenous substance into muscle, but to the fact that they sup- ply carbon for the production of heat and energy, and thus prevent the albuminoids from being used for this purpose.
220. Starvation. When the food is insufficient to meet the needs of the animal, not only is waste left unrepaired, but fat that had previously been de- posited is re-absorbed into the blood and burned in place of food. If the deficiency of food continues, the muscular substances will also be attacked and absorbed. This process will continue until the ani- mal can no longer obtain from its own tissues material to produce, by its combustion, sufficient heat and energy to maintain the vital processes, and the animal dies.
§ 6. Effects of Exercise and Exposure to Cold.
221. As we have already seen, the first use of food is for the production of heat and energy. When an animal is exposed to cold, the amount of heat re- quired to maintain the temperature of the body{will be increased, and a larger proportion of the food con- sumed by the animal must be used in its produc- tion.
222. Physical work can only tbe performed by means of the energy derivedffrom the_combustion of
119 SCIENCE IN FARMING.
food in the system. Consequently every increase of physical exercise increases the amount of food that must be used in the production of energy.
228. The first effect, therefore, of exposure to cold, or of exercise, is an increased appetite, by which Na- ture indicates that more food is needed. If the in- creased food is not provided, the effect on the animal will be re-absorption of fat, and, in extreme cases, waste of muscular substance.
CHAPTER LIX. SCIENCE IN FOODS.
N 1. Food Constituents.
224. Food is composed of yarious organic sub- stances combined in varying proportions. Vegetable substances will vary in composition according to the soil and season, and the treatment they have received. All statements of the composition of food are there- fore approximate only. The nutritive constituents of foods are usually classed as:
Albuminoids.
Amides.
Fats.
Soluble carbohydrates.
Crude fibre.
Ash.
225. The term albuminoids is used to include all nitrogenous matters in food that can be used for the formation of albuminoids in the animal system. In a great many analyses all the nitrogenous substances in the food are classed as albuminoids. In many substances this is unavoidable, as the proportion of the nitrogen contained in the amides has not yet been
determined in all cases. 8
114 SCIENCE IN FARMING.
226. Amides cannot be used by the animal for the production of albuminoids, but can be burned in the system as a source of heat and energy. They exist principally in roots and immature substances.
227. The term “soluble carbohydrates” in analy- ses of foods includes all non-nitrogenous substances (excepting ash and fats) that can readily be dissolved by weak acids or the juices of the stomach.
228. Orude fibre includes the coarser and harder portions of cellulose and lignose that are not readily dissolved by weak acids or the juices of the stomach
229. In many analyses of foods the division is made into flesh formers, heat producers and ash. Un- der the term “flesh formers” are included all nitro- genous substances, and under ‘“ heat producers” all that do not contain nitrogen. The terms, however, are incorrect and misleading.
§ 2. Composition of Foods.
230. The figures in the following table give the average results of anumber of analyses. They repre- sent about the composition of any ordinary lot of food, but cannot be relied on as positively accurate, as the composition of different samples of the same kind of food is rarely the same. The variation in com- position is but small in seeds and grains, but in roots, straw and fodder is often quite considerable. The column of “ Total nitrogenous matter’ may, in most cases, be considered reasonably near the truth, but some doubt exists as to the figures in the column of ‘True albuminoids,” owing to the uncertainty with regard to some foods, particularly roots and fodder, as to the proportion of the nitrogen that exists in the
FOODS.
115
form of amides and nitrates.* In many cases it has
POUNDS OF EACH CONSTITUENT IN ONE TON OF VARIOUS FOODS.
Pea aE Say eS : 4 : B46 gle S| Sass | Name of Foood. 3 lSne ae 8 \2Selc8 ; = O° gifs 4 5 aa ah Fie Cle eibe mee GRAINS, CAKES, ETC. ; Cotton cake, decorticated ..... | 200} . 824 | 740/280! 360 | 180 Cotton cake, undecorticated...| 230} 492 | 443/124) 604 | 416 PieCd CAKE. sa. ks ac ens 240} 562 | 506/240} 606 | 220 MMM Ree Yee see as 290} 510 | 459! 32) 918 | 188 EEE Ay eee) SSS het ad's 286; 448 | 404) 40) 1050 | 128 2 SSRs ee one 260} 258 | 232/120) 1076 | 216 “2 SS SR Saag ee go ae ee ee 288] 226 | 203] 30) 1362 60 LE hee eit 2 AR area SPP 280| 212 | 191] 40) 1274 | 142 LS BS SS ee eee 286; 220 | 198} 40] 1884 | 70 (SGN 900) gh ee 228} 208 | 187/102) 1370 | 60 Rete Marne ft ace dd Oy | 280}. 284 | 200) 84) 1008 | 222 HT TG eee a 206} 28 2? | 28) 880 | 756 HAY AND STRAW. Menmew hay 2. Seed wed 286; 194 | 155) 50; 820 | 526 BROWSE NAY ooo ty ss ede 320} 246 | 196) 44) 764 | 520 Lucerne hay, cut in bloom ....; 334) 288 | 230) 50) 450 | 800 WCAG BEPAW fe cds 286} 60 ? | 30) 652 | 880 Na oS ace ek idk ody oe a a 286 50 ?| 40) 764 | 800 LORS es 280} 60 2] 22) 780 | 800 GREEN FODDER. Meadow Sfases. 6.2 oe e.c e505. 1600; 70 2?) 16) 384] 90 EE BLE is oa ies Selita saat kes 1660 66 2) 14) 140 90 5 RR Eig 1458 66 2] 18} 298 | 146 Ducerme, id blossom... ....5.; LASO RE TOO oe Are Ag. 1 ah eee ele Nee ea h lees yen 1630 64 Pi) 164s bade Hungarian grass in blossom...!1312) 118 | ?| 30} 300 | 230 RRR Gee asf. Danis pith «de 1480} 50 2? | 28) 306 | 146 Pridtan cork iiss 2 wa. 1644 22 PP DOb s 218 ee94. ROOTS, ETC LE aie les aan ae er 1500 42 20| 6) 410 22 Manecl wurzel’ 3) dec. oso 3 1770} 24 6; 2) 164] 20 ESRD et ESA a sa oven a 8 18354 22 10; 4) 106 20 i110) 2 A ae Aa na 1890} 26 Bh Reheat +20 Sugar beets, small ............ 1630) 20 2 -2l -808)) 326 Oy SUIn eS Re ee I eee ge 1700, 30| ?| 4| 216 | 34
not been possible to give the amount of true albumi-
noids.
*It was formerly supposed that all the nitrogen contained in
116 SCIENCE IN FARMING.
231. The composition of straw depends very much on the season. In seasons that have been unfavora- ble for maturing the grain, the straw contains consid- erably more soluble carbohydrates and albuminoids than indicated in the table (192). Only a small por- tion—probably less than half—of the nitrogen in straw exists in true albuminoids.
232. The composition of hay depends greatly on the date of cutting. The following table gives the number of pounds of nutritive substances in a ton of hay made from grass cut at three different periods. The first date represents grass younger than it would usually be cut for hay, but such as cattle get ona good spring pasture. The second date represents good early cut, well cured hay. The third date rep- resents a quality of hay cut rather late, and rather
coarse and stemmy: May 14. June 9. June 26.
Nitrogenous matter.......... 303 191] 145 Beret ae cee te ey men mint ads 5d 47 46 Soluble carbohydrates....... 700 742 743 Crude aubrey eke. fr. eticods be cian 394 598 654
It will be seen from this table that grass in early spring contains a larger proportion of nitrogenous matter and fat than it does later in the season. In the more mature crop, however, a larger proportion of the nitrogen is contained in true albuminoids.
233. Root crops,as they approach maturity, con- tain more valuable nutritive constituents than when
foods was available for the use of the animal, and the albumi- noids were reckoned by first ascertaining the amount of ni- trogen contained in the food and multiplying this by 6.25. Many errors have arisen from this method, as in some foods as much as 75 per cent of the nitrogen exists in amides and ni- trates. Foods have thus been supposed to have a high albu- minoid ratio (255), when in fact they were very deficient in al-
buminoids.
FOODS. Whi
immature, a portion of the fibre being converted into starch and sugar.
234. Water in Foods.—It will be noticed that pota- tos, the dryest of the roots, contain three-fourths of their weight of water, while turnips are nine-tenths water. This is a matter that is of considerable im- portance in determining the proper mixture of foods, and will be more fully considered in the next chapter.
235. Variations Caused by Soil and Season.—Foods grown in wet seasons and on heavily manured soil, usually contain more than the average per cent of water (178). Root crops grown on rather poor soil contain a larger per cent of nutritive matter than those grown on soil that has been heavily manured. The dry substance in a crop grown on soil that has been heavily manured, usually contains a larger per cent of ash and of nitrogen than the dry substance of acrop grown without manure. A larger portion of the nitrogen in the manured crop will be in the form of amides and nitrates.
236. Effect of Methods of Preparing Foods.—Hay that has been roughly handled contains a smaller pro- portion of valuable constituents than that which has been more carefully treated, as the finer portions of the blades and leaves, which contain more albumi- noids and less crude fibre than the stems, are crum- bled and broken off. Clover, especially, is liable to deterioration in this way, as the leaves, which are rich in albuminoids, crumble readily when too dry. The chemical composition of a ton of clover which had been roughly treated, would be quite different from that of a ton which had been properly cured. If grass, after cutting, is exposed to drenching rains, part of the soluble constituents"will be washed out,
118 SCIENCE IN FARMING.
and its composition will therefore show a larger per- centage of crude fibre. Hay that has undergone fer- mentation in the field will have suffered a further loss of soluble carbohydrates by their conversion into car- bonic dioxide and water.
When properly handled and cured, the composition of hay does not differ materially from that of the grass from which it was made.
§ 3. Digestibility of Foods.
237. The composition of a food cannot be taken, alone, as a trustworthy indication of its feeding value, as this will depend largely on its digestibility. Some foods are almost entirely digested, while of others more than half is sometimes rejected (217).
238. An animal does not always digest the same proportion of each constituent in a food, nor the same proportion of the same constituent in different foods. Thus, a cow will digest a much larger proportion of the albuminoids in lucerne hay than of those in clover hay, and will digest a larger proportion of the fat in clover hay than of that in lucerne hay. The digesti- bility of foods thus influences not only their compara- tive feeding value, but also their relative character. Thus the difference as an albuminoid food in favor of lucerne hay over clover is greater than indicated in the table on page 115. Likewise the table shows lu- cerne hay as containing a larger proportion of fat than clover; yet so much more of the fat contained in clo- ver is digested, that as a food it is really richer in fat than lucerne. It will thus be seen that while such a table as given on page 115 is very useful for many purposes, yet, taken alone, it cannot be depended on
FOODS. 119
to determine either the value of a food, or its char- acter.*
239. The following table gives the number of pounds of digestible constituents in a ton of several different foods as determined by experiments with cattle and sheep. It will be noticed that in many re- spects.it differs materially from the last table:
Name of Nitrogenous Soluble Car- y-1__. Food. renee te Be bohydrates. pre Linseed cake ........... 472 216 473 i iatep tr (eee has Pia ea 3 854 f OS a ae 204 101 818 52 Lo ee 163 40 1108 2 PRGA G COGN.) .. fc.2%. . 164 87 1247 ? Witteat dram ooo... 213 42 706 82 Meadow. hay <.......... 109 23 508 300 lower Way. es... 3 ay: 135 25 527 229 ibnceme hay os 219 19 301 320 Patreerawy 19 12 329 488 Wreatistraw .,)..5... +: 12 11 254 494
240. In this table it was impossible to make any accurate calculation of the amount of true albumin- oids in the digested portion of the food. It will prob- ably be safe to assume, however, that true albumin- oids formed 90 per cent of the digested nitrogenous matter in the cakes and grains—80 per cent in hay and 50 per cent in straw. Roots appear to be almost completely digested.
241. The horse digests a smaller proportion of coarse foods than ruminating animals, but on grains and concentrated food his digestion is equal or superior to theirs.
242. Pigs have great powers of digesting concen- trated food, and can digest a good proportion of green foods when supplied in moderate amount, but they
*By the “‘character’’ of a food is meant its richness in any particular constituent, as albuminoids or fat,
120 SCIENCE IN FARMING. ‘
do not successfully digest large quantities of coarse food.
243. The degree of maturity of a crop has much to do with its digestibility. Young grass is more di- gestible than that which is older. The number of pounds of food constituents in a ton of hay cut at different dates was given in paragraph 232. We now give the number of pounds of digestible food constitu- ents in a ton of hay cut at the same three dates:
May 14. June 9. June 26.
Nitrogenous matter.......... 222 138 80 Baba dc ceca Rewer eee a 36 24 20 Soluble carbohydrates....... 53 459 414 Crude fibre oes, . ose sao 393 400
By comparison with the preceeding table, the great depreciation in the value of the crop, as it approached maturity will be noticed. Not only does the older grass contain a smaller proportion of the more valu- able constituents, but a smaller proportion of what it does contain is digested.
For this reason, young grass or clover pastured, or cut and fed green gives greater returns in beef or milk than the same amount of grass allowed to ma- ture and made into hay. This also explains why cat- tle do so well on spring pastures.
244. Digestibility of Food as Affected by Mixing.— To secure the most complete digestion of food, a cer- tain proportion between the nitrogenous and non-ni- trogenous constituents must be secured.
245. If, to a diet of hay or straw, a food rich in al- buminoids is added, the digestibility of. the whole ra- tion is not impaired, but if to such a diet a food de- ficient in albuminoids is added, the proportion of the hay or straw digested will be diminished. Potatos, and other foods rich in starch, have a greater effect
FOODS. 121
in reducing the digestibility of a diet with which they are mixed than mangels or other roots rich in sugar.
246. Iftoadiet of hay or straw, potatos or some similar food is added, and also some food rich in albu- minoids, such as peas, beans, or linseed cake, the di- gestibility of the diet will not be reduced.
247. The results of experiments in this direction show that in order to secure the most perfect diges- tion of food, the diet must contain a certain propor- tion of albuminoids. If a diet is mixed in such a manner that it does not contain a sufficient proportion of albuminoids, a larger percentage of all the nutri- tive constituents in the diet will remain undigested. It is therefore important in determining on a mixed diet to consider what its albuminoid ratio (255) will be, and to so proportion the food that this ratio (cal- culated from the whole food) will not fall below that which secures the most perfect digestion of all the food constituents. The proper albuminoid ratio will be considered in the next chapter.
§ 4. Valuation of Foods.
248. For development of muscle no comparisons can be made between albuminoids and non-nitrogen- ous substances, as only the albuminoids in the food can be used for this purpose. If a diet is deficient in albuminoids, the addition of a sufficient quantity of them will have an effect out of all proportion to the actual value of the albuminoids.
249. As albuminoids, carbohydrates and fats can all be used for laying on fat, or can be consumed in the system for the production of heat and energy, it is easy to make a comparison of their respective values for these purposes. By careful experiments
122 SCIENCE IN FARMING.
these values have been determined, as follows:
BG Se he I Bo ge. Lo SS le 100 POllalvteetuatone ls Meee epee te Oy oe, enn 2 47.4 Carbohydrates? 5 0.0 ek. csc sa ae 43.1
These figures refer to the value of the digested por- tions of the food. A given weight of a very digesti- ble carbohydrate might be of more value than an equal weight of an indigestible fat, but the proportion be- tween the value of 1 lb. of digested fat and 1 Ib. of di- gested carbohydrate is that of 100 to 48.1. That isifa given weight of fat in a food were worth $1.00, an equal weight of albuminoids would be worth 47,4,ths cents, and an equal weight of carbohydrates, 43;,th cents.
250. The rule usually adopted in comparing the value of fats with carbohydrates is to multiply the amount of fat by 2.44. That is, if one lot of food con- tained 100 Ibs. fat and another 244 lbs. carbohydrates, they would be estimated of equal feeding value.
251. ‘To illustrate. By reference to the table in paragraph 239 it will be seen that a ton of linseed cake contains 216 lbs. digestible fat, and 478 lbs di- gestible carbohydrates. To estimate the feeding value of the digestible constituents in a ton of linseed cake, we multiply the fat by 2.44 and add to this the carbo- hydrates. Thus:
NIN DEE-OF DOUMGS fo ee iccs he Vee eee 216 Multiply by ie oS 2. s eae ee Be ee 2.4 4 864 864 432 Equal in carbohydrates to. 2030.5 eee tlek 5 2.7.0 4 Acidscarbolyd rates. 4 1a tee. wes same te ae 473 1000.04
*This includes all digestible non-nitrogenous food constitu- ents except fats.
FOODS. 123
By which we see that the feeding value of the digestible non-nitrogenous constituents in a ton of linseed cake is equal to 1,000;4,ths lbs. of starch or other digestible carbohydrates.
252. Therule for reducing fat to its equivalent value in starch, or other digestible carbohydrates, is: Multiply the number of pounds of fat by 244 and point off the last two figures in the product for deci- mals.
253. As already stated, the value of a food, pro- viding it contains a sufficient amount of albuminoids to meet animal requirements, depends on its capacity for the production of heat and energy. By taking the digestible constituents of different foods and re- ducing them all to their value in carbohydrates, their respective values have been approximately deter- mined.
254. The following table gives the result of these calculations, Indian corn being taken as the standard with which the others are compared. The first column gives the respective values of foods in their ordinary condition, the second column the respective values of the dry substance in these foods:
Ordinary Con- Dry Sub- Name of Food. dition. eo PHGVARCOPW tc. ere Sa ea te 1 Tea ga RaS tes 100 Panaecd caker so. oy. fe Oe hes. erate AE 96 WES aN aris taksicvescioas eda ake chs Se pete REY MeO ae dRea 96 MMMM Mi No okie sn Sarees a SNE so sige ree aig 88 a eh ckiy es dak So) S| REY a dgeoe 1 gale Ae Se 81 ABER OTE oo oii lc otc view ochewe EF PRN ace 2 SEE Nee 69 IMetdtiw: NAY re ee es Oleg ate tees hk ote 61 WWeat straw 25622 2 feel eos BARRIERS ie 49 PERU: Ses ea ky Se Gee eet ites wiley eta 105 TPE MORSE ES A a Bisiasy Paee t eh8 100
*It may appear strange that linseed cake is given a position as a food inferior to Indian corn. It must be remembered that
124 SCIENCE IN FARMING.
The figures for the last: five articles are probably too high, owing to the fact that proper deduction has not been made for the amides and nitrates.
§ 5. Albuminoid Ratio.
255. The “albuminoid ratio” of a food is the pro- portion that exists between the albuminoids and the non-nitrogenous constituents.
It is customary in calculating the albuminoid ratio of a food to take into consideration the digestible por- tion only, as the portion undigested of course has no feeding value. When the digestibility of the different constituents of a food is not known, the albuminoid ratio must be calculated from its total constituents. A food will usually appear richer in albuminoids when the estimate is made from the table of digesti- ble constituents than when calculated from the table of total constituents, as there is usually a larger per- centage of carbohydrates, fat and fibre rejected, undi- gested, than of albuminoids.
256. ‘Tio secure strict accuracy in the determina- tion of the albuminoid ratio, the calculation skid be made from the amount of true albuminoids only, as the amides and nitrates are without value in the production of muscle. Nearly all the older calcula- tions are erroneous from this cause, as it is only lately that the distinction between amides and true albu- minoids has been learned. It is still sometimes nec- essary to make calculations in this way, as, with some foods, the proportion of nitrogen which exists in true albuminoids has not been ascertained with
this table is calculated only on the capacity of the food for pro- ducing heat and energy. Linseed cake mixed with other foods may, by increasing the albuminoid ratio of the mixed diet, have a value many times greater than that of corn,
FOODS. 125
certainty. Calculations made in this manner will be reasonably correct with respect to grains and concen- trated foods; but with roots and immature substances such calculations are liable to be seriously incorrect. Thus, mangels were formerly supposed to contain suf- ficient albuminoids to form a complete ration, their albuminoid ratio being 1:8, when calculated on the supposition that all the nitrogenous matter they con- tained was in albuminoids; but when only the true albuminoids were reckoned, the ratio was found to be 1: 31.8 (263).
257. To determine the albuminoid ratio of a food, the feeding value of the digestible non-nitrogenous constituents is ascertained, and this is divided by the amount of albuminoids. The product is the proportion of non-nitrogenous to one of nitrogenous constituents.
258. Illustration.—Suppose the albuminoid ratio of wheat bran is desired. By reference to the table in paragraph 239, we find that a ton of wheat bran con- tains the following amounts of digestible constituents :
Lh) OU TIIE T gan c n a e avE Pa e a 213 lbs. MRO eR oa ans Reh Rh aaiet aint lane g Pal, 6 Syne « akc diet as 42 lbs ry OEALOR, fo tinsss tisk riz gins bie stags eg aha 706 Ibs UMM rs SEG EN pe RS eka HS so eee Pay Raa A ctety the 82 lbs. First reduce the fat to its equivalent in starch (250) ON os IMMEG I re Re ER 42 Ibs. Pitiply by seek Laas 2.4 4 168 168 Bao aie ge eM The fat is equal in starch...... 102.48 lbs. Add digestible carbohydrates.. 706 Ibs. And digestible fibre........... 82 Ibs. 890.48 lbs.
*In this instance it is necessary*to reckon all the nitrogenous
126 SCIENCE IN FARMING.
Which gives us the feeding value of the digestible non-nitrogenous constituents of a ton of branas equal to 890.48 lbs. To get the proportion between this and the albuminoid, we divide it by the number of pounds of albuminoids. Thus:
213)8 9 0.4 8(4.18 852
384 213
1718 1704
We thus get the proportion of one to four and eighteen one-hundreths, which is written thus: 1: 4.18.
259. When the proportion of albuminoids in afood is large, it is said to have a high albuminoid ratio. When the proportion is small, that food is said to have alow albuminoid ratio. Thus the albuminoid ratio of decorticated cotton cake is1:1.5; that of wheat straw 1: 64.4; cotton cake is said to havea high, and wheat straw a very low, albuminoid ratio.
260. To Determine the Albuminoid Ratio of a Mixed Diet.—This is a matter of great importance, as it ena- bles the farmer to know whether a mixed diet is prop- erly proportioned to meet the desired object.
261. Rule.—Ascertain the number of pounds of each digestible constituent in the amount of each food used in the mixture; add these and calculate the al- buminoid ratio of the product, the same as in any other case.
262. Illustration.—Suppose a farmer wishes to use
matter in the bran as albuminoid, as the per cent of amides contained in the digested portion of bran has not been fully de- termined.
FOODS. 197%
a mixed diet arranged in the following proportion:
WEG MIEV I ile oc tatec fe oases es oak Bane edeee es 100 lbs. CDSE TS 1 el ie aE Se 20 lbs. Rea Ti ee on i so oc 2 su pe 20 lbs
By reference to the table in paragraph 239, we learn the amount of each digestible constituent in one ton of each food named, and by a simple calculation we obtain the number of pounds of digestible substance in: Nitrogenous pay Carbohy- Bibrat
Matter. drates.
100 lbs. meadow hay... 5.45 1.15 25.40 15.00 20-1bs., corn meal. :..... 1.64 .87 fe 7 a seca Beetes. DEAN... cao | bs a 13 .42 7.06 .82 Total in whole ration... 9.22 .44 44.93 15.82
Reducing the fat to its value in starch (250), we get the value of the digestible non-nitrogenous con- stituents in the diet:
eee ee OSs CQUISL TO: Si be ru ea, So ele wee 2 5.95 lbs. eR RUE OR 5c a cciines hake oo 3's safes nnn giess Ain kt 44.93 lbs. Py POE) ee ee pete eer eas UT Pea ar 15.82 lbs.
Remi yamerequal-tot Yar estate. Cea 66.70 lbs.
From which we find by the usual rule (257) that the albuminoid ratio of the mixed diet is 1 : 7.23.*
263. The following table gives the albuminoid ra- tio ef various foods, calculated from the digested por- tions only. The first column gives the ratio as deter- mined by calculations made on the supposition that all the nitrogenous substances in the food are true al- buminoids. The second column gives the ratio as de- termined by estimating only the true albuminoids. The figures given in the first column for cakes and grains are nearly correct. The true ratio for turnips
*It will be noticed that this calculation is made on the sup- position that all the nitrogen is in albuminoids, and the ratio thus obtained is therefore rather above the truth.
128 SCIENCE IN FARMING.
would probably be about 1:12, and of wheat straw not more than 1: 100; for clover hay about 1: 9.
ALBUMINOID RATIO OF THE DIGESTED PORTION OF FOODS. Reckoning all Ni- Reckoning on-
Name of Food trogenous matter ly the true asalbuminoids. albuminoids.
Cotton cake decorticated ......... ] ba Cotton cake undecorticated....... 1 1.8 Haingpeedsedke pratt daue se he 1 2B SCAG ete dice eer ere hag ede ] 2.4 PEAS Aah Re MTR BES tar od ] 2.9 Wy neat joram: os ite cet oe ee lies Ae 1 7 LODE ATS.» Sha 08 BGP AE OR NOE 2 Sea See 1 55 Barley. oS ae va ate anaes 1 aie Indian corn..... Ty Sth Meee 7 si oS Deco) Clowerthigy xe 6 ute saa a jateal 5.9 Mieadioweliay sc.104 52). coir ise sk bat 1 eae) 1: ee PURER Sart ha ec nite, et try Oce BN Wes OE. ’=) fan a ce Meo UA iN pen ey” a eas 2S See POtatos ly era Pee aa let le 1 hO6 Le ee Wea SER 24 ree aoe ee ne ee 164.4:
264. The same food may have a different albumi- noid ratio when fed to different animals, as one may digest a larger proportion of the albuminoids, and the other a larger proportion of the carbohydrates. In one experiment a horse and a sheep were fed on the same meadow hay. The portion of the hay digested by the horse had an albuminoid ratio of 1 : 6.7, while the portion digested by the sheep had a ratio of 1: 9.1. This difference was due to the fact that the horse di- gested as large a proportion of the albuminoids in the hay as the sheep, but the latter animal digested a larger proportion of the carbohydrates and crude fibre.
CHAPTER. X. SCIENCE IN FEEDING.
§ 1. General Principles.
265. The practical objects to be attained in feeding are:
1. To cause growth—development of bone and mus- cle—in the young animal.
2. The production of milk.
3. The production of fat.
4. To furnish material from which the animal can derive energy to be employed in useful work.
A fifth might be added—namely, the production of manure, but this will be considered in the next chapter.
266. While food is being supplied for these pur- poses, a sufficient amount must also be furnished to repair the wastes of animal substance (206), maintain the heat of the body, and furnish the energy required in the vital processes (212).
267. We have seen (203) that the plant is the ma- chine by which inorganic substances are converted into forms that can be used by the animal. To the farmer, the animal is only a machine for the conver- sion of vegetable substances into flesh, fat, milk, wool ee and for the development into useful work of the
130 SCIENCE IN FARMING.
energy which the plant has obtained from the sun and stored in the food.
268. Ifasteam engine attached to a mill requires 20 Ibs. of coal per hour to overcome the resistance of the machinery and only that amount is supplied, no useful work can be accomplished. If the supply of coal is increased to 30 lbs. per hour, the energy de- rived from the 10 lbs. added would be available for grinding. If 401bs. per hour is supplied, the available power will be that of 20 lbs. of coal. Thus by the last increase of 10 lbs. the work which can be accom- plished is doubled.
269. The same principle applies to the science of feeding. Ifan animal which requires 20 lbs. of food per day to repair the waste of tissue and carry on the vital processes receives only that amount, no part of this food can be applied to growth, production of fat or milk, or in useful work. If a larger quantity of food is supplied, the additional food can be used for profitable increase.
270. The animal is, in fact, engine and mill com- bined. Into the same hopper is put the grist to be ground and the fuel to drive the engine. Only that which is furnished in excess of the amount required to keep mill and engine running and in repair pays any profit to the owner. Of this excess part is ground up and worked over into profitable forms, and part is used to supply the additional energy needed for the purpose.
Underfeeding is therefore extravagance.
271. Adaptation of Foods.—It is not only necessary that the animal should have sufficient food, but it must be adapted to the object desired. If the food supplied to a growing animal is composed chiefly of
FEEDING. 131
non-nitrogenous matters, these cannot be converted into muscle, and either growth will be checked or an excess of food must be supplied—and a portion of the carbohydrates be wasted. If on the other hand the food contains a larger proportion of albuminoids than is needed, while the animal will not suffer, as the al- buminoids will meet all its needs (210), yet as they are much more expensive than carbohydrates, the farmer’s profits will be greatly diminished.
272. Effects of Exercise—We have seen that the physical energy in the animal is derived from the combustion of the carbon of the food in the blood (211). The greater amount of physical effort required the greater amount of the food consumed will be used for this purpose.
It has been ascertained by experiment that a man when doing a fair day’s work, gives off from his lungs one-third more carbonic dioxide than in an equal time when at rest, which proves that when at work one- third more food was burned in the system.
Hence all unnecessary exercise on the part of an animal causes a waste of food. When cows are driven long distances to and from pasture, are com- pelled to roam over closely cropped fields in search of food, or worried by flies, or chased by dogs and boys, the farmer may know that the energy,thus,ex- pended is obtained by the combustion of food that would otherwise be converted into milk and butter.*
*The greatly increased production of butter and cheese claimed by the advocates of soiling, is partially explained by the fact just given. The cows kept in a quiet and*comfortable stable, protected from annoyance by flies and spared all un- necessary exertion, can put into the pail a quantity of butter, that, were they roaming over a large pasture and fighting flies, they would be obliged to burn~for the production of physical
132 SCIENCE IN FARMING.
273. Effects of Cold—Exposure to cold results in loss to the farmer in much the same manner as excess of exercise. The animal heat must be maintained and food will be burned in the system in proportion to the demand for this purpose. Food which the an- imal should be manufacturing into fat, flesh or milk, is burned to keep the animal warm. A farmer would be considered extravagant who would put up a stove to warm his stable and feed the fire with butter, but when he leaves his cows exposed to cold and storms, they have to keep warm by burning the butter which would otherwise go into the milk pail.
274. In some experiments with sheep made to as- certain the amount of food required to produce one pound increase of live weight, it was found that 150 lbs. of turnips were required to produce this amount of increase when fed to sheep which had no protec- tion from storms and cold, but that the same result was obtained by feeding 100 lbs. when the sheep were protected.
275. The Kansas State Board of Agriculture re- cently made some experiments in fattening pigs. A number were put in pens and fed and treated alike, with the exception that part of the pens were in the basement of a barn and part were out of doors. It was found that one pound of increase was made from 5.15 lbs. of corn fed to the pigs in the barn, but that
energy. Men who have had no experience in soiling, often wonder how it is possible that the food grown on an acre should produce any more milk and butter when cut and fed to animals in the stable, than when the same animals gather it for themselves. They do not see the butter burned to enable the cow to wander after her food, and fail to appreciate that it is burned as truly as if put into the fire-box of an engine.
FEEDING. hoo
5.48 lbs. corn were required to make one pound of increase in the pigs fed outside.
Too great heat is also wasteful, as it occasions per- spiration and food must be consumed in its evapora- tion.
276. Effect of Water in Food.—A certain amount of water is necessary to the life of the animal, but if an excess is contained in the food waste will be oc- casioned, as the water must all be warmed to the temperature of the animal and a part must be evapo- rated through the skin. Considerable food must be burned to produce the heat thus required.
277. The proper proportion of water is, for sheep about two parts to one of dry substance; for cattle, four parts to one. Cows giving milk require a still larger proportion of water.
278. In feeding grains and dry fodder;there is lit- tle probability of supplying too much water, but in feeding roots alone the quantity of water is liable to be greatly in excess of the animal’s requirements. When an animal is fed exclusively on turnips, a large part of the dry substance consumed will be used in raising the temperature and evaporating the surplus water.
- 279. Hence, roots should usually be fed in connec- tion with dry food, and when fed in this manner, will give much better results than when fed alone.
§ 2. Proper Food for the Young Animal.
280. The chief object of the food supplied to the young animal is to produce bone and muscle, as the production of a large amount of fat is not desirable. The food, therefore, should be rich in albuminoids, phosphoric acid and lime. The milk —called colos-
134 SCIENCE IN FARMING.
trum—which Nature furnishes for the young animal at birth, is exactly fitted for the purpose designed. The following table gives the analysis of the colos- trum of the cow:
Water ee ice Te ee dee CD emt Mie) ies BS Ue i 716 PAT SIMA RATOT Bt oe capa Me Fit tapas tc-Liaig ce ce eehyle anaes 207 C2 pees he Sat ESTO iy hn AM Dot SA ¢ om ae ria Ue Ok AE 34 OEE PES DN ager RL ta yamine aE a teed Sly Sie hs Pai ice aia 25 NCSL TUM Gs Aer gad NOOR NSS Vo I ae a COs ana Miedo PCO RS YI fo 18 1,000
The albuminoid ratio is about 1: 0.5. The ash, which is also in large proportion, is principally calcic phosphate. This food is therefore specially adapted for producing bone and muscle. During the first few days of its life the animal takes but little ex- ercise; consequently the amount of carbonaceous food required is not large. The character of the milk soon changes, as the needs of the animal change. The milk contains more fat and sugar, and less albumi- noids and ash. The following is the average compo- sition of cow’s milk:
PUN EE iP Bt ORI ise Si a eae na highest 07 Cm 870 A TD UMN OLAS 2c iy eae. ecaigee eee) ALY emcee aka Me Poe 40 Ch Eat eer TM ADIL aeL OER Ae snied Ui eer) aR eet. oy os 37
Ne LDF) semen Bern DEMS Me TUG AME easel amen NODA ae fia Scag TA 46 UA ST eer MAN ay SIERO Wes ttae cea ile ald act aed os Oe a 6 1,000
The albuminoid ratio is now only 1 : 3.3.
The composition of milk gives the key to the proper food for the growing animal.
281. It should be readily digestible and contain a fair proportion of fat. Carbohydrates can take the place of fat; but as 2.44 lbs. carbohydrates are re- quired to equal 1 lb. of fat, a less bulk of carbona- ceous food will be required when fat is provided, and the animal will thus be able to consume more albu-
FEEDING. 135
minoids, which are essential for the development of bone and muscle. The food must also contain a due proportion of phosphoric acid and lime.
282. By reference to the table of foods (230), it will be seen that young clover and grass are rich in albuminoids. They also contain a considerable per- centage of phosphates, and therefore form a suitable diet for the growing animal. Bran makes a good ad- dition to such a diet, and a little linseed cake will supply the fat and albuminoids.
283. Many of our best farmers have adopted the plan of putting their growing pigs on grass or clover pastures, and feeding but moderately with corn. This enables the pig to grow and develop a large, bony and muscular carcass, with capacious digestive organs. When the time arrives for fattening such an animal, it can consume large quantities of food, and produce a proportionately large amount of fat.
284. The proper albuminoid ratio for a growing animal is 1:5 to 1:7 When all the nitrogenous matter has been reckoned as albuminoid, in determin- ing the ratio, it should not be less than 1: 5.
§ 3. Proper Food for Producing Milk.
285. As milk contains a large proportion of albu- minoids and phosphates, the food must contain enough of these substances to meet the demands for milk in addition to what is required to supply the wastes of tissue. Ifthe food does not contain enough of these substances, the flow of milk will be diminished, or the cow must use her own tissues for its production. The food should also contain some readily digestible fat, as we have seen that this is contained in milk in considerable quantity (280).
136 SCIENCE IN FARMING.
286. Ifa food is deficient in albuminoids, the cow may be fed all she can eat, and yet be unable to yield a liberal supply of milk.
287. As the bulk which a cow can eat is limited, the food should be tolerably concentrated; otherwise it will not be possible for her to obtain a sufficient amount of nutritive substances in the quantity she is able to eat
288. For example. By reference to the table in paragraph 239, it will be seen that a ton of wheat straw contains only 12 lbs. of digestible nitrogenous matter. Not more than half of this is in the form of true albuminoids. As 25 lbs. of milk contain about 1 Ib. albuminoid, it would be necessary for a cow fed on wheat straw alone, to consume (in addition to the amount required to repair the wastes of her tissues) 3334 lbs. straw in order to produce 25 lbs. of milk. It is true that a cow could not eat such a quantity of straw in a day, but it would be as possible for her to do so as it would be for her to give a liberal flow of milk on such a diet. This explains why farmers who winter their cattle at the straw stack find it impossi- ble to make butter in winter.*
289. Pea and bean meal, linseed and cotton cake are rich in albuminoids. Bran and clover are also ni- trogenous foods and contain a considerable proportion of phosphates, Mangels supply valuable carbohy- drates. A diet of good clover or meadow hay, with
*A cow could hardly keep alive, much less give milk, fed on pure wheat straw. Practically a straw pile always contains a little grain and some other substances, and the cattle ‘ pick up” alittle food besides. The usual condition in spring of cattle wintered at the straw stack, is, however, a sufficient evi- dence of the correctness of the scientific principles that have been laid down.
FEEDING. 137
mangels, bran and a small amount of linseed or cot- ton cake, bean or pea meal would be a good milk diet from a scientific stand-point, and practical expe- rience has approved it.
290. The value of young meadow grass as a milk diet is well known. The fact that cows on pasture decrease in flow of milk as the season advances, is also a familiar one. This is caused by the decrease of albuminoids in the older grass. By reference to the table in paragraph 2438, it will be seen that 100 Ibs. of hay, cut May 14th, contained a little over 11 lbs. of digestible albuminoids, while the same quantity cut June 26th, contained but 4 lbs. The cow cannot eat more grass in summer than in spring, and therefore if at each period she has all the grass she can eat, she will by June 25th get but four- elevenths as much albuminoids as she would May 14th.*
291. Wolf gives the albuminoid ratio of a milk diet as 1: 5, reckoning all the nitrogenous matter as albuminoids. Reckoning only the true albuminoids, a ratio of 1:6 or 1: 7 will be sufficient.
292. Meadow grass cut May 14th has a ratio of 1: 4.14 (reckoning all nitrogenous matter). That cut June 26th has a ratio of only 1:10.76. The first, there- fore isa rich milk diet, while the latter falls far below the requirement.
293. Analysis of aftermath hay shows that while it is no richer in albuminoids than the first crop, it is very considerable richer in fat. The following table
*This further explains the advantages claimed by the adyo- cates of soiling. Under this system the cattle are kept con- stantly supplied with fresh young grass and fodder, cut at the time when it is richest in nitrogenous constituents.
138 SCIENCE IN FARMING.
gives the number of pounds of food constituents in a ton of aftermath hay :
Wie ter foe 252i) Ge pm mane MIO 2g oid sete gta 237.4 Ibs. NITTOREMOUS IMaAtLeR elem ae dk, fas soweher ie 196.8 lbs. poluble-carbohiyedeates were ee se se Ss es 845.0 Ibs. ae Wey OK AG ane N CME NEN AE CC 0 wd Kies 136.8 Ibs. Cirle MBG re vo ee PE ANS. ae ce MS 395.4 Ibs. PALRIEL AM BS Rte ee PMMA OEE ng gnc ID 188.6 lbs.
2,000.0 Ibs.
Such hay if fed with sufficient nitrogenous food to secure a proper albuminoid ratio, would make a bet- ter milk diet than the first crop.
294. Mr. I’. Horsfall, of England, made some of the most complete experiments on the diet of milk cows. He first calculated a diet from scientific prin- ciples, and then applied to this the test of practical experiment. The ration for each cow per day con- sisted of:
cada Day. Facil cert sawn aa era ge mre ae 9.33 Ibs. EVAR HO RIRD 2 lu Sy OC snGe er as 1 a ee Ae ee ea Gio Wles NTE CORA IOS ota hn a ohne Uh ns Una an sie ame 1b. tee Wiheatibrain 072 oe yo ce SDI oe Rae 1.57 sie: Rear ae e ty ith tuts ee i ae Ne apse, 9h Ulan ae ees Leb. ose CE TECTIAOGGEE fr oo rs Pek eee Age chee GEREN S eee 34... dbs CALTSETUIR Ee Wee een eee tee ER ee ae ee 8.33 lbs. Beam IStha Wer sss eee os eRe Chita hi. DN aie ate Pe lbs
PROBA A Gate ote Seth Ce ae Aa ee oc en Mlb a 63.16 lbs.
The rape cake, malt combs, wheat bran, beans and bean straw made this a highly nitrogenous diet, the albuminoid ratio being 1:5.4. The rape cake fur- nished a considerable quantity of fat. In some parts of the country rape cake and malt combs cannot be obtained. Linseed or cotton cake can be substituted, and a diet fully equal to Horsfall’s be obtained. If neither of these can be had, an approach to the ration could be made by increasing the proportion of bran —using clover or Hungarian grass and some corn meal.
FEEDING. 139
Mr. Horsfall’s cows on this diet gave a large quan- tity of milk, of which 16 quarts yielded from 24 to 28 ounces of butter. And the cows gained in weight.
§ 3. The Fattening Animal.
295. The chief constituent in the increase in a fat- tening animal is fat. In experiments at Rothamsted it was found that the increase of weight in a fattening sheep consisted of:
ST Ui en tae Aah Sy rn bry Weta ahs Saag ee 22.0 PRO SeNOUA MAIER Hos fee on Keer bd ee foie ae he 7.2
MM secs an nk A bint LL Rigi BRA Aces Sp auee st a 68.8 EP SNE PTR ER ala A BO a Pe eR cnr 2.0
The increase contained nearly ten times as much fat as muscle.
296. Theoretically, therefore, the fattening animal requires a diet containing but a small proportion of albuminoids. Practically, however, it is found that when the ratio falls as low as theory would indicate could be used, the digestibility of the food is im- paired and the health of the animal suffers (247).
297. The albuminoid ratio* of food for a fattening animal has been ascertained to be:
Gr OMG ee Bee vee ek as sya EW oe ig eminee ae ce Bye a a tes) PR EOE Le teh AE Od Sade ee ot aes Ba eau Foe 9 1ST R a SA OA an AR a lL gi ee Nt AU ae 1 Tey's
298. A diet richer in albuminoids may often be used with advantage when not too expensive. Food excessively rich in albuminoids, as cotton cake, is liable to produce disease if fed in large quantities. Such substances should always be fed moderately and in connection with other foods.
299. Experiments in Fattening.—The following ta- ble shows the result of some experiments made by
*Reckoning only the true albuminoids.
140 SCIENCE IN FARMING.
Messrs. Lawes & Gilbert, of Rothamsted, England, for the purpose of determining the amount of food required to produce an increase of a pound of live weight, and the relative capabilities of different ani- mals for converting food into meat. In the experi- ment, the oxen and sheep were fed on linseed cake, clover hay and sweedes; the pigs on barley meal:
RESULTS OBTAINED PER HUNDRED POUNDS LIVE WEIGHT PER WEEK.
Oxen. Sheep. Pigs. Dry food received per week per
hundred pounds live weight.... 12.5 16.0 27.0 Which contained of digestible sub- SLANGE Le Oe ial, | See eee Red ele 8.9 12.3 22.0
Amount of food expended per week
in production of heat and energy
for each 100 lbs. live weight.... 6.86 9.06 12.58 Gain in live weight per week for
each 100 Ibs. of live weight of
AMS Mt enh ins hee eee 1.13 1.76 6.43
The student will understand from the above table that an ox weighing 1,000 lbs. consumed per week food containing 125 lbs. of dry substance, of which he digested 89 lbs. 68.6 lbs. of this was used in the pro- duction of heat and energy, and 11.3 lbs. stored as in- crease in live weight. The remainder of the digested matter was expended in repairing the wastes of the body.
300. The table also shows that a sufficient number of pigs to weigh 1,000 lbs consumed per week food containing 270 lbs. dry substance, of which they di- gested 220 lbs. 125.8 lbs. of the digested matter was used in the production of heat and energy, 64.3 lbs. stored up as increase, and the remainder expended in repairing waste of tissue.
301. These experiments show that the pig eats more in proportion to his weight than the ox, but he also
FEEDING. 141
makes a larger amount of increase in proportion to food consumed.
RESULTS OBTAINED PER HUNDRED POUNDS DRY FOOD USED. Ox: Sheep. Pig.
Received by animal............. 100 100 100
LD le Sto) 203 DUET RS ae SG Se a 72.2 76.9 81.5 Used for heat and energy ....... 54.9 56.6 46.6 Laid up in increase............. 9 ih 23.8
By the term 100 Ibs. dry food is meant an amount of food containing 100 lbs. dry substance.
302. It will be noticed that the pig digested a larger proportion of his food than the ox. This was not due to the better digestive powers of the pig, but to the fact that his food contained a larger proportion of digestible material. Calculating therefore only on the digestible portion of the food, we get the follow- ing table, showing the amount of increase in live weight produced from 100 lbs. digested dry substance —thatis, from an amount of food containing 100 lbs.
of digestible dry substance: | Ox. Sheep. Pig.
Increase in live weight per 100 Ibs. CUseRLeO LOOM 2.5. .:e2 65 eae wie 12.7. 14.8 29.2
It will be seen that the pig produced a far greater amount of increase from a given amount of digestible food than either the sheep or the ox, showing that he is the most profitable machine which the farmer can use for the conversion of his crops into meat.
303. The table in paragraph 299 shows that even in these experiments, where the animals were care- fully treated, and no unnecessary food expended in the production of heat and energy, the amount of food consumed for this purpose was far greater than that stored in the increase.
304. The fact that the pig uses a larger proportion
142 SCIENCE IN FARMING.
of the food he consumes in production of increase than the ox, and less for heat and energy, explains the reason why he requires a diet richer in albumin- olds.
305. The fattening animal does not make the same rate of increase, nor yield the same profit on food consumed during the whole fattening period. As the animal increases in size and weight, it can eat less food in proportion to its weight, and probably digests a smaller proportion of what it does eat. It also uses a larger proportion of the digested food for production of heat and energy and repair of waste.
306. Anexperiment was made at Rothamsted with 16 pigs, averaging 135.8 lbs. at the commencement of the fattening period, and 276.3 lbs. at its completion. The food consisted of 7 lbs. pea meal per day for each pig, with all the barley meal in addition that they would eat. The pigs were fed for ten weeks and weighed every two weeks. The following table gives the result. The number of pounds of food refers to the food in its ordinary condition—not to the dry sub-
stance:
Food con- Food consum’d Food consum’d sumed per per 100 lbs live to produce 100
head. weight. Ibs increase. First two weeks .... 60.1 Ibs. 39.7 lbs. 386 lbs. Second two weeks .. 67.5 Ibs. 36.7 lbs. 388 lbs. Third two weeks ... 66.4 lbs. 30.9 lbs. 502 lbs. Fourth two weeks .. 66.0 lbs. 27 4s. 511 Ibs. Fifth two weeks .... 69.6 lbs. 26.3 Ibs. 618 lbs. Average for ten w’ks 65.9 Ibs. 32.0 Ibs. 469 lbs.
307. During the first two weeks 3.86 Ibs. food pro- duced 1 lb. increase; but during the last two weeks it required 6.18 lbs. to produce that amount. Calcu- lating that 90 per cent of the increase was butcher’s carcass, it required during the first two weeks only
FEEDING. 143
4.29 lbs. food to produce a pound of pork; but during the last two weeks 6.88 lbs. to produce that amount. The pork made during the last two weeks therefore cost 60 per cent more than that made the first two.
308. In experiments made in feeding pigs in the United States, it was found that 5.33 lbs. corn was re- quired to make 1 |b. increase in live weight, while in the English experiment just given, the average for the whole period was 1 lb. increase from 4.69 lbs. food. The difference in favor of the English experiment was probably due to the fact that the food used—a mixture of pea and barley meal—had a much higher albuminoid ratio than corn.
309. Corn does not contain a sufficient proportion of albuminoids to make a perfect diet for fattening pigs. Consequently the addition to a corn-diet of a small amount of some highly nitrogenous food, as linseed cake,* or bean or pea meal, greatly increases the value of the whole food.
310. Skim milk is a highly nitrogenous food. Its percentage composition is about:
SPE LAS MT DERE Say CA ie ae e AER gC a ey erg a 90. PCEDENTIBII OLS Feo Se SRS le a ge Ae kta eee ae re cree eee EO SRN OL COMIN oe WN TRY hal Ra 0.8 Rrrn eee eet he Bei tad SS La eee ae Rain tLe cen hae 4.8 SUNT eS ee Rede ed Oe Cone EN eee Oe Wo RD, tls sei Bi 0.7
157.4 Ibs. skim milk contains as large an amount of albuminoids as a bushel of corn. We have seen that a pig requires a diet having an albuminoid ratio of 1:7, and that the ratio of corn is only 1:9. Ifa pound of skim milk is fed with every pound of corn,
*Linseed cake can only be fed in small quantity, or it will injure the flavor of the pork. +The nitrogenous matters in milk are all true albuminoids
144 ~ SCIENCE IN FARMING.
the albuminoid ratio of the whole diet would be 1:6.4 —a ratio sufficient to secure the best results.*
311. The entire increase of live weight in a fatten- ing animal is not useful carcass. As the animal grows the digestive organs also grow. The increase of offal is not as great proportionally as the increase of butch- er’s carcass, and consequently the highly fattened animal contains a larger percentage of carcass and less percentage of offal than the animal in “store” condition only.
312. In fattening a sheep, from 68 to 77 per cent of the increase is carcass.
318. Of the fatted animal, about 60 per cent of the fasted live weight is carcass in the ox, 58 per cent in the sheep and 83 per cent in the pig.
§ 4. The Working Animal.
314. A working animal, if it has been properly grown, will contain a large amount of muscular sub- stance and a comparatively small proportion of fat. To replace the waste of this muscular tissue will re- quire a fair amount of albuminoids in the food. Be- yond this, carbohydrates and fat meet the require- ments of the working animal. It has been found that an albuminoid ratio of 1:9 is sufficient for an adult horse at work.
315. It would seem that a horse not at work would require about as large an amount of albuminoids as a working horse, but a smaller amount of carbohy
*This explains why persons who have but one or two pigs and give them the skim milk and scraps from the table, are so successful. The small quantity of food rich in albuminoids added to the corn, raises the character of the whole diet, and better results are obtained from all the food given.
FEEDING. 145
drates, and that therefore the albumiinoid ratio of his diet should be higher.
316. In growing an animal intended for work, the object is to produce the largest possible development of muscle, and but a small development of fat. There- fore the food for the young animal intended for work should be rich in albuminoids—bran, oats, peas, beans,
clover, etc. S6.. Summary.
The only profit which the farmer can secure in feeding, is that from food supplied in excess of the amount required to keep the animal alive and in health.
It is not only necessary that the food be sufficient in quantity, but its character must also be adapted to © _the purpose desired. Lack of care and judgment in this respect is likely to result in injury to the animal, waste of some of the food constituents supplied, or the use of unnecessarily expensive foods.
In arranging a mixed diet, the effect of the mixing upon the digestibility of the food must be carefully considered, otherwise, much of the food supplied may remain undigested, causing waste and loss.
The greater the amount of food, a fattening animal can be induced to eat and digest, the greater will be the profit obtained in proportion to the amount of food consumed. Therefore the flavor of the food, and the degree in which it is relished by the stock, have an important influence on the profits of feeding.
Exertion, and exposure to cold require a large consumption of food which gives no returns in flesh or fat, therefore, economy requires that fattening stock be protected from the weather, and spared all un- necessary exercise.
146 SCIENCE IN FARMING.
The increase of weight produced from a given amount of food is greater in the young animal than in the old, and greater in the beginning of fattening than towards its close. Therefore, a careful estimate should be made of the cost of the food and the value of the meat produced, so that the farmer may know at what time to sell his stock in order to secure the largest profit on food used.
In fattening pigs, improvement in their health, and, therefore, in the profit of the farmer, has been secured by keeping them supplied with a mixture of 20 lbs. sifted coal ashes, 4 lbs. salt, and 1 lb. superphos- phate of lime.
CHAPTER XI. Ss SCIENCE IN FERTILIZERS.
§ 1. General Principles.
317. <A fertilizer is a substance which, if added to the soil, will increase its capacity for the production of acrop. The science of fertilization includes all methods of rendering the soil more productive.
318. ‘The production of a good crop depends on the soil and the season. Over the former, only, the farmer has control, and it is his business to provide a condi- tion of soil that will secure the largest crop the sea- son is capable of producing.
The conditions of soil necessary for this are: A sufficient amount of plant food, in a form that can be used by the crop;
Such a mechanical condition of the soil as will en- able the roots of the plants to reach and use the avail- able plant food present.
319. Nature and Cultivation—We have seen (145) that in a state of nature the amount of plant food in the soil tends continually to increase. Under cultiva- tion where crops are carried away, the amount must
148 SCIENCE IN FARMING.
decrease, unless in some manner the plant food taken away from the soil is restored.
320. Favorable mechanical conditions of the soil are obtained by cultivation, drainage, and sometimes by plowing under green crops (See ‘ Soils,” sections 5, 6, and 7).
321. Plant food in the soil is rendered available by drainage, cultivation, the use of lime, bare fallow, and by plowing under green crops (See “ Soils,” par- agraphs 161-163).
322. The amount of plant food in the soil is in- creased by the addition of manures.
323. The methods necessary to secure favorable mechanical conditions of the soil also tend to increase the amount of plant food by favoring absorption from the air, and to render that which is present available, by favoring nitrification and the solution of mineral substances.
324. The methods necessary to render plant food available, also usually improve the mechanical condi- tion of the soil, and by favoring absorption, tend to increase the total amount of plant food in the soil.
325. The addition of manures frequently improves the mechanical condition of the soil, and may also, by starting chemical action, render the plant food al- ready present, more available.
It is therefore impossible to draw a strictly accu- rate line between these different methods. The farmer must usually employ all three, and in order to attain the best results, their judicious combination is necessary.
The methods of improving the mechanical condi-
FERTILIZERS. 149 tion of soils have been considered in chapter six. § 2. Rendering Plant Food Available.
326. Bare Fallow.—This is one of the oldest meth- ods of improving the condition of soils. It is often called “ resting the land,” but the term is unscientific and misleading. In a bare fallow the land is allowed to remain one season without a crop, and is contin- ually cultivated in order to keep down weeds, and ex- pose the soil to the action of the air. Except by fa- voring the absorption of ammonia from the air, it does not increase the amount of plant food, but by favor- ing oxidation, a portion of the mineral substances is rendered soluble, and by nitrification the nitrogen contained in the humus of the soil is converted into nitric acid. Under favorable circumstances, a large amount of nitrogen—sometimes as much as 35 to 55 lbs. per acre—will be converted into nitric acid, and the soil be able to produce a double crop the year suc- ceeding the fallow.
In some experiments at Rothamsted, one part of a field was cropped with wheat four years in succession; another part was cropped and fallowed alternately. The soil was the same and no manure was used. The following table gives the yield per acre for the four years, the field that was cropped continuously being marked No. 1, and the field fallowed each alternate
year, No. 2: Field No. 1. Field No. 2.
LATS) oc ae i Be ae 15.87 bu. Fallow Dec VOUE i eer sec. 2 13.81 bu. 37 bu. PENCE VERT oi cll ios ees 15.81 bu. Fallow PPR VERE Sse 1s) Se es Sie 21.06 bu. 42 bu.
Total in four years........ 66.55 bu. 79 bu.
In this experiment the field that was alternately
150 SCIENCE IN FARMING.
cropped and fallowed, produced in the four years a total of nearly 124 bushels per acre more than the other. As, in this case, one-half the seed and nearly one-half the labor of harvesting were saved, the fal- lowed field was the more profitable.
Producing a heavy crop alternate years by means of a bare fallow, simply draws on the supply of plant food in the soil.
If heavy rains fall on a bare fallow, much, or in some cases all, of the nitric acid formed may be washed out. The constant use of the bare fallow as a means of securing large crops therefore tends, un- der ordinary conditions of soil and climate, to the ul- timate exhaustion of the nitrogen in the soil.
327. Lime.—The principal effect of the application of lime is to favor the decomposition of humus in the soil. The amount of plant food furnished is unim- portant, as nearly all soils contain sufficient to supply the needs of any ordinary crop. The use of lime is therefore classed among the methods adopted for rendering plant food already present in the soil available. Its principal value for this purpose is on soils that. are over-rich in humus (174). The persis- tent use of lime without other manures, therefore, tends to greatly reduce the total amount of nitrogen in the soil. While valuable when properly used, many farms have been almost ruined by its injudi- cious application. Lime is also sometimes useful on clay soils, by improving their mechanical condition (170). In this manner it may not only render a clay soil more easy to work, but also increase its capacity for absorbing and retaining fertilizing elements.
328. Green Manuring—Growing green crops and plowing them under is properly classed as one of the
FERTILIZERS. 151
methods of rendering plant food available. It is true that a large portion of the crop was obtained from the air, but that portion is not of value as plant food in the soil. The nitrogen* and mineral elements in the plant were obtained from the soil, and the actual quantity of these elements in the soil is, therefore, not increased.
829. Green manuring renders the plant food in the soil available:
By gathering that which is already present, form- ing it into organic substances which are left near the surface, and as they decay, give up to the succeeding crop that which they have gathered.
By taking up the nitric acid as rapidly as formed by nitrification, and thus preventing it from washing out in the drainage water.
By shading the soil, keeping it moist, and loose, and thus providing the circumstances favorable for nitri- fication.t+
*The leaves of plants absorb from the atmosphere some am- monia (142), and the nitrogen contained in this is gained by the soil when the crop is plowed under. The quantity thus obtained is, however, so small and so uncertain that it cannot be taken into consideration in practical estimates.
+Numerous experiments appear to indicate that under cer- tain circumstances the free nitrogen of the air which is con- tained in the pores of the soil, may be oxidized into nitric acid. The circumstances necessary are, a porous soil, rich in humus, a certain amount of moisture, warmth, and the presence of some base with which the nitric acid can combine as rapidly as formed. The presence of ferric oxide in considerable quan- tity seems to aid the action by catalysis (122). Should future experiments demonstrate that this oxidation of free nitrogen can be accomplished to any considerable extent under the in- fluences which the farmer can control, the present views of the operation of green crops will require serious modification. It will then appear possible, by green manuring, not only to change the nitrogen in the soil into more available forms, but
152 SCIENCE IN FARMING.
By attacking plant food existing in the soil informs of combination not available for other crops. Legu- minous crops (clover, peas, beans, etc.) appear to have the power of feeding on nitrogenous substances in the soil in forms that are not available for cereal crops. This nitrogen it leaves in forms of combina- tion that readily undergo oxidation with production of nitric acid. Hence clover, even when the crop is cut for hay and seed, leaves in the roots and stubble a large amount of plant food that can be used by the succeeding crop.
§ 3. Manures,
330. The plant takes from the soil a large number of substances, but in practice only three have to be considered. These are:
Nitrogen.
Phosphoric acid.
Potash.
The other mineral elements of plant food are equally essential, but they are usually contained in the soil in sufficient quantity, and most manures that contain nitrogen, phosphoric acid and potash, also contain these other substances. These three are the ones to be considered in estimates of the fertility and exhaus- tion of soils and in the valuation of manures.
331. We have seen (158) the amount of these sub- stances in a very fertile soil. The following table
also to add to its quantity. With our present knowledge on this subject, however, it will not be safe for the farmer to de- pend on increasing his store of nitrogen by this means; what- ever future discoveries may be made, the wise farmer will still carefully save and return to his soil all waste plant food,
FERTILIZERS.
shows the amount taken from an
153
acre by an average
crop: re
S 23
° a 2
s 2 5
4 a = 20 bushels wheat........-- 22 ibs. 9.5" lbs: 6.4 lbs. 2000 Ibs. straw.........--- 9.6lbs. 5.2Ibs. 11.6 lbs. aval: GEO oviside Hee </< 31.6 lbs. 14.7 lbs. 18. lbs. 30 bushels barley......--- 26.2 lbs. 12.1 lbs. 7.3 Ibs. 18000 lbs. straw........--- 9 Tpst 3:6 lbs. 17.4 bs: Popal CVO. om bes oe = 35.2 lbs. 15.7 lbs 27.7 Ibs. 30 bushels oats.....-..:.-. 25.3 lbs. 7.9 lbs 5.7 lbs. 1800 Ibs. straw: >... ..-2-- 9.0 lbs. _ 4.5 lbs. 18.7 lbs. Vota erop. ii e2 2s. i. 34.3 lbs. 12.4 lbs. 24.4 Ibs. 20 bushels rye .....------- 19.7 Tbs. 9.4 Ibs. 6.3 lbs. 3240 lbs straw ......----+. 13.0 lbs. 6.8lbs. 25.2 Ibs. Wotal Crop 2.94246 .9->>" 32.7lbs. 16.2 lbs. 31.5 Ibs. 50 bushels Indian corn .... 41.4 lbs. 12.8 lbs. 10.8 lbs. 8000 lbs. cornstalks........ 88 4]lbs. 424]bs. 76.8 Ibs. Total. Grop:.., 2: s<)-15+. 6 79.8 Ibs. 55.2 lbs. 87.6 lbs. 2 tons meadow hay.......- 62.0 lbs. 15.2 Ibs. 67.2 lbs. 2 tons clover hay......---- 78.8 lbs. 22.4lbs 78.0 lbs. 15 tons turnips..........-- 54.0 lbs. 18.0 lbs. 87.0 lbs. 9000 Ibs. tops..-... «.---- 388. 6lbs. 8.4]bs. 31.7 Ibs. Potal GvOpec. j2: 3-22 92.6 lbs. 26.4 lbs. 118.7 lbs. 20 tons mangels.......---- 76.0 lbs. 28.0 lbs. 156.0 lbs. 16000 lbs. tops .......---- 44.7lbs. 13.3]bs. 62.7 Ibs. otal Crop ict. ssn. shee <> 120.7 Ibs. 41.3 Ibs. 218.7 lbs. 100 bushels potatos......-- 20.4 Ibs. 10.8 lbs. 33.6 lbs. 2000 Ibs haulm...... .---- 9.3 lbs. _ 3.0 lbs. 8.1 Ibs. Mahal GLOW. sis « 0,0 ec > 99.7 lbs. 13.8lbs. 41.7 lbs.
332. It would require a great many years to re- move all the nitrogen, phosphoric acid and potash from a soil (even were it possible to continue to grow crops until the whole amount was exhausted) but that
154 SCIENCE IN FARMING.
which is in an available condition may be exhausted in a few years.
333. It is also necessary in order to produce a full crop, that the soil should contain considerably more of these substances in an available form than the crop will require, for no plant can gather all the available plant food in the soil. Thus we see that a crop of wheat of 20 bushels to the acre, contains only about 32 lbs. of nitrogen, but such a crop cannot be grown unless the soil contains at least 65 lbs. available nitrogen.
334, The means employed to supply the required available plant food, and prevent the deterioration of the soil by too heavy drafts on the supply it contains, are the application of farm-yard manures and com- mercial fertilizers.
030. Farm-Yard Manure consists of the excrements of the animals fed upon the farm, mixed with the straw used for litter, and other waste products of the farm.
336. Commercial Fertilizers consist of various im- ported and manufactured articles with the refuse from slaughter houses, ete., worked up into a condensed form ready for immediate application.
$4. Harm-Yard Manure.
307. Composition.—This varies greatly, depending on the kind and amount of litter used, the character of the animals producing it, the food used, the length of time the manure has been kept, and the treatment it has received.
338. Water forms the greater part. The remainder consists of carbonaceous matter With a small amount
FERTILIZERS. 155
of nitrogenous substances and mineral salts. The fol- lowing table gives the composition of one ton of av- erage fresh farm-yard manure.
Niet eye Og ee Te Tire ON 0 oS en oe ar 1,420 Ibs. LATICES ORR ge i Ss ag 9:1 be. Le USC To Ge 0 UA, ara een 4.2 lbs. ORES Sn ae eet i Toe ane eno ee 10.4 Ibs. Carbonaceous matter, lime, sand, etec., ..... 556.4 Ibs.
Siete es Ft ee Oo es Oak kek 2,000 Ibs.
This represents an average sample of fresh manure. It will be seen that one ton contains only 23.6 lbs., of valuable plant food. Farm-yard manure from ani- mals fed on rich food may contain a much larger amount.
339. Fermentation of Manure.— When fresh manure is allowed to remain in a heap, decomposition soon ‘commences. The carbon combines with oxygen from the air, producing carbonic dioxide which is given off. The nitrogen combines with hydrogen of the water forming ammonia. If the manure has become dry, this ammonia combines with the carbonic dioxide forming carbonate of ammonia (112), which escapes in vapor. Ifthe heap has been kept moist, it com- bines with the organic acids formed by the decompo- sition of carbohydrates, producing soluble but not vo- latile salts.
340. Considerable heat is produced during this process, which drives off much of the water in the manure. By fermentation of the manure, the amount of water and carbon in the heap is decreased, while the amount of nitrogen and mineral salts (if the pro- cess has been properly conducted,) remains un- changed. The manure, therefore, contains a larger proportion of these substances than before fermenta- tion, and more of the nitrogen is in an available form.
156 SCIENCE IN FARMING.
341, Manure Fermented in a Heap in Open Yard.— The following table shows the weight of a ton of ma- nure fermented in a heap in an open yard, and the amount of nitrogen contained in the heap at different
dates: Total Weight
of Manure. Nitrogen. November arduetnwe nk agit ces 2,000 lbs. 12.9 lbs. fa Ug bce O13 i Rn ead a ea’ Morar 1,428 lbs. 12.8 lbs. ANI UIStEAardi ms Oia lee) 3 1,405 lbs. 9.3 lbs. November? loth. (552) fj. bos 1,391 lbs. 9.2 lbs.
The manure used in this experiment contained con- siderably more nitrogen than that of which the analy- sis was given in paragraph 338. It will be noticed that during the first six months the weight of the ma- nure was reduced nearly 29 per cent, while the loss of nitrogen was immaterial. A ton of the manure ana- lyzed April 30th would have contained 20.2 lbs. of ni- trogen. During the next 6 months the decrease of weight was very small, but the loss of nitrogen was quite serious. A ton of the manure on November 15th would only contain about 13 lbs. of nitrogen. By fermenting for six months in winter the weight of manure that would have to be handled to obtain a given amount of nitrogen was decreased, but by fer- menting six months longer nitrogen was wasted and the amount of manure required to contain a given weight of it was as great as at first.
342. Manure Fermented Under Shed.—T'he follow- ing table shows the result of an experiment in fer- menting manure under a shed:
Total Weight
of Manure. Nitrogen. Novyeriberard soe so eh ark 2,000 Ibs. * AZ OAs: Api aO Tiss). iia ie ds Sk Le 992 lbs. 10.2 lbs. AUQTISG ZAvOs Oy oe a eats cals lara? 800 Ibs. 10.2 lbs.
November Loti. =... eke lee 758 lbs, 11,4 lbs,
FEEDING. 157
In this case the manure lost more than half its weight in the first 6 months, but it also lost 2.7 lbs. nitrogen per ton. This was probably due to the heap having been allowed to become too dry. During the next four months the heap lost in weight but not in nitrogen. On August 23rd the heap contained nitro- gen at the rate of 25.5 lbs. per ton. It will be noticed that the last date shows an actual increase in nitrogen. This must have been due to error in the analysis, un- less sufficient free nitrogen was oxidized in the heap to cause the increase. We have not sufficient facts at present to warrant this last supposition.
343. Manure Spread in Barn-Yard.—The following table gives the result of an experiment with manure left spread in an open barn-yard:
Total Weight
of Manure. Nitrogen. Wovember Sra? . 05.051. oo: 2,000 lbs. 12.9 Ibs. BAPTA EN cc bias Sy ve whee «Sd 1,730 lbs. 9.2 lbs. MPU EEL es se de een 1,226 Ibs. 5& Ibs. November 15th. 20). oo 1,150 lbs. 4.5 lbs.
In this case nitrogen was constantly lost, so that at the end of the year but little over one-third remained. The loss of nitrogen was in greater proportion than the loss of weight, so that the manure at the close of the experiment contained a smaller proportion of ni- trogen than at its commencement.
344, Leaching.—When manure is exposed so that the rain which falls upon it leaches through, great loss of its most soluble, and therefore most valuable constituents is incurred. A heap of ordinary manure containing a ton of dry substance contains only 31 lbs. of nitrogen and 35 lbs. potash, while sufficient of the dark colored drainage from the manure heap to contain one ton of dry substance would contain about
158 SCIENCE IN FARMING.
166 lbs. nitrogen and 554 Ibs. potash. The nitrogen in the drainage is also entirely soluble, and hence much more valuable than that which remains.
345. Evaporation of Ammonia.—We have seen (339) that the evaporation of ammonia may be prevented by keeping the heap sufficiently moist to insure the production of organic acids. It can also be prevented by the addition of gypsum or land plaster (109). Sulphuric acid diluted with water and sprinkled over the manure heap also prevents this waste by the for- mation of sulphate of ammonia, but it is neither as cheap nor as convenient as land plaster.
346. Care of Manure.—From the facts already given the following practical applications may be made:
By the fermentation of manure it loses carbon and water, causing considerable loss of weight and bulk, but if the fermentation is properly conducted there will be little or no loss of valuable constituents. —
If the manure while fermenting is allowed to be- come dry, serious loss of nitrogen will ensue.
If so much water is allowed to fall on the manure that it leaches through and escapes by drainage, great loss of all the valuable constituents will result, and the exhaustion may be so complete that what re- mains will not be worth hauling to the field.
By the use of gypsum loss of nitrogen by evapora- tion can be avoided.
347.—Concentration.—It costs as much to haul and spread a ton of poor manure as a ton of the best; con- sequently there is economy in having manure as con- centrated as possible. If a farmer has two heaps of manure, one weighing five tons and containing plant food worth $2.50, and another weighing only one ton but containg the same amount of plant food—and if
FEEDING. 159
the cost of hauling and spreading is 50 cents per ton, the net value of the two heaps will be as follows:
Five-ton heap containing plant food worth ........ $2 50 Less cost of hauling and spreading at 50 cents a ton 2 50 Mer wala dermenmsi ested oa i SEE Re es $0 00 One-ton heap containing plant food worth......... $2 50 Less cost of hauling and spreading at 50 cents a ton 50 PURE OCR GOIN: 7. Shem. yy ho kde ents ole sae tiw dig so 4 ae $2 00
$5. Manure from Different Animals.
348. There is quite a difference in the manure pro- duced by different animals. The following table gives the average amount of water, nitrogen, phosphoric acid and potash in a ton of the fresh manure from different stock, the manure including solid and liquid excrements mixed with litter: —
Phosphoric Pare
Water. Nitrogen. aa ierses. >)... 1,426 lbs. 11.6 lbs. 5.6 Ibs. 10.6 lbs. Cattle: «i= ;.. 1,550 Ibs. 6.8 lbs. one LOS: 8. Ibs: mheep ..4.. 1,292 Ibs. 16.6 Ibs. 4.6 lbs. 138.4 Ibs. Swine ..... 1,448 lbs. Te lpss 3.8 lbs. b2e- lpg:
Poultry*... 1,120 Ibs. 32.6.lbs: 30.8 Ibs. Ley lbs:
The manure from cattle and swine contains much more water than that of the horse and sheep, and con- sequently ferments less rapidly. In popular language, the one is said to be cold and the other warm. To se- cure the best results in fermenting manure, it is well, when possible, to have the manure of all the different animals mixed in one heap. This gives a composi- tion that causes fermentation to progress favorably.
349. Solid and Liquid Manure.—There isa great dif- ference in the composition of the solid and liquid ex crement of animals. The former contains the greater part of the phosphoric acid; the latter usually con-
*Fresh, but without litter.
160 SCLENCE IN FARMING.
tains more of the nitrogen and potash. The manurial constituents in the solid excrement are mostly insolu- ble ; those in the urine are entirely soluble.
The following table gives the amount of plant food contained in one ton of the fresh solid and liquid ex- crement of different animals:
. Phosphori Nitrogen. ee ae Potash.
Horse, solid excrement... 8.8 lbs. 7 Ibs. / loge eh ag MOREE, Wa eas 2s a eas ale i Wn | oY. ee emery 30 Ibs. Cattle, solid excrement... 5.8 lbs. 3.4 lbs. 2 Ibs. Ret a OMA RS ae Lip Ibs... “cyvbeeoe 9.8 lbs. Sheep, solidexcrement... 11 lbs 6.2 Ibs. 3 Ibs : PINGS Son Al cutee: 39 Ibs. .2lbs. 45.2 lbs Swine, solid excrement... 12 lbs. 8.2 lbs. 5.2 lbs. Jobin) Sh igh ct: Meee ee De a Rone 8.6 lbs. 1.4lbs. 16.6 lbs.
The respective values of the different manures will be considered in a later portion of the chapter.
The composition of manure varies with the consti- tution of the animal and its food. Analyses can there- fore give averages only.
§ 6. Relation of Food to Manure.
350. The plant food in the manure must come from that contained in the food supplied to the animal. In the animal body a portion of the carbonaceous matter is burned up, and the product thrown off by the lungs (207), but nitrogen, phosphoric acid and potash are not disposed of in this manner. All of these sub- stances except what is used by the animal in the pro- duction of milk or increase, will be found in the ma- nure.
_ 851. If an ox is given food containing 100 lbs. dry substance, he will produce manure containing about 364 Ibs. dry substance, and in this manure will be the greater part of the nitrogen, phosphoric acid and pot- ash that was contained in the food supplied. As the
FEEDING. 161
quantity of dry substance in the manure is much less than that in the food from which it was pro- duced, while the quantity of plant food is nearly the same, it follows that the dry substance in the ma- nure will contain a larger proportion of plant food than is contained in the dry substance of the food. The amount of plant food in the manure, however, cannot be greater than that contained in the food from which it was produced.
302. Cause of Difference in Manure.—If a ton of corn is fed to an ox, and another ton to a sheep,* and all the manure collected, there will be exactly the same amount of plant food in the manure produced by each animal while feeding on the ton of corn’; but as the ox will have produced the larger quantity, his manure will contain the smaller proportion of plant food.
303. The difference, therefore, in the value of ma- nure produced by different animals is due to the fact that some remove more of the carbonaceous matter from the food supplied, and leave the manure propor- tronally richer. But no animal can furnish in the ma- nure any more plant food than is contained in the food it receives.
Manure produced by animals fed on poor food will therefore be poor, while that produced by those fed on rich food will be rich. A ton of clover hay con- tains four times as much nitrogen as a ton of wheat straw ; therefore, other things being equal, the ma- nure made by feeding a ton of clover hay will con- tain four times as much nitrogen as that made by feeding a ton of wheat straw.
*In this example it is supposed that neither animal is in- creasing in weight. 11
162 SCIENCE IN FARMING.
354, Proportion of Manure to Food— When an ani- mal is neither increasing in weight nor giving milk, the manure produced will contain exactly the same amount of plant food that was contained in the food consumed.*
This is evident from the fact that the solid excre- ment contains all the nitrogen, phosphoric acid and potash of the undigested portion of the food; and all of these substances contained in the digested portion, except what is used in the production of milk, stored up in increase of weight, and used for the repairs of the waste, is carried off in the urine. If the animal is neither growing nor giving milk, the urine will con- tain all these constituents except the amount used in repairing waste. The wasted substance is taken up by the blood and removed by the kidneys, and ex- actly balances the amount used in repair.
395.. When the animal is giving milk a portion of the nitrogen and phosphoric acid will be removed in the milk, and the manure produced will not usually contain more than from 50 to 75 per cent of the amount of these substances supplied in the food.
356. When an animal is growing rapidly a consid- erable portion of the nitrogen and phosphoric acid contained in the food is used in the production of bone and muscle, and the manure contains a propor- tionally smaller amount of these substances than the food.
357. The fattening animal takes comparatively little valuable material from the food, as the greater
*This, of course, includes all the manure both solid and liquid. In the manner in which manure is often saved, or rather wasted, it would contain but a small portion of the plant food furnished the animals.
FEEDING. 163
part of the increase is fat, which contains no plant food. The following table shows the proportion of the nitrogen supplied in the food, that is stored up in increase, the proportion voided in the solid and liquid excrement, and in both, in fattening oxen, sheep and pigs:
Oxen. Eber Pigs.
Per cent nitrogen stored in increase ... 3.9 14.7 Per cent nitrogen voided in solid excre-
PDE Vea RA Ma emer set. eee | CLO. Cat) BE Per cent nitrogen voided in urine...... fae Ato 64.3 Per cent nitrogen voided in total excre-
PIES Reh eee tes Ow ate cata ee OG:1" * O77) 85.38
With the fattening ox and sheep the manure con- tained about 96 per cent of the nitrogen supplied in the food. As the pig uses a larger proportion of the food he receives in production of increase, and less for heat and energy, the per cent of nitrogen supplied that goes into the manure is less than with either of the other animals.
358. Of the phosphoric acid and potash contained in the food of a fattening animal, from 95 to 100 per cent will be found in the manure.
359. The proportion of nitrogen received in food that is voided in solid and liquid excrement will vary with the kind of food supplied, and the table just given will therefore only be correct in this respect when the diet is the same as that on which the table was calculated. As the manurial ingredients in the di- gested portion of the food are voided in the liquid ex- crement and that in the undigested portion in the solid, the more digestible the food the larger pro- portion of manurial ingredients will be contained in the liquid excrement. Thus, we have seen that a ton of wheat straw contains 60 Ibs. nitrogenous matter (230), but that only 12 Ibs. of this is digested (239).
164 - SCIENCE IN FARMING.
If an animal were fed on wheat straw alone, there- fore, the solid excrement would contain at least 80 per cent of the total nitrogen voided. By the same tables it will be seen that of the nitrogenous matter in beans, 88 per cent is digested, and therefore when an animal is fed on beans, the greater part of the nitro- gen voided will be in the urine.
360. As the plant food contained in the solid ex- crement is mostly insoluble, while that in the urine is soluble, a pound of nitrogen in urine is worth more than the same amount in the solid excrement, and therefore the more digestible the food the more valu- able will be the plant food in the manure produced.
361. We obtain from the foregoing facts the fol- lowing rules:
The proportion of plant food in the manure will depend principally on the proportion in which it is contained in the food supplied to the animal.
The plant food in the manure will be more valu- able in proportion as the food supplied to the animal is more digestible.
Manure produced from working or fattening ani- mals will contain from 90 to 95 per cent of the manu- rial constituents contained in the food.
Manure made from milk cows and young, growing animals, will contain from 50 to 75 per cent of the ma- nurial constituents contained in the food.
362. Animal Food as Manure.—At one time rape cake was largely used in England as manure, it being sown with the seed. In this country cotton seed meal has been used for the same purpose, and some experi- menters have tried bran as a manure.
363. We have already seen that the greater part of all vegetable substances is carbonaceous matter,
FEEDING. 165
valuable as food for animals but not as food for plants. For example, a ton of bran contains 1,044 lbs. of di- gestible food for the animal (239), but it only contains 138.2 lbs. manurial constituents (372). If this ton of bran is fed to fattening oxen, the manure, if all saved, would contain about 152 lbs. of manurial constituents, while the remainder of the food might produce an in- crease of weight in the oxen of 130 lbs. There would therefore be a gain of 130 lbs. of weight in the oxen to compensate for the loss of six pounds plant food. The plant food inthe manure would also be in more available forms than in the bran, and the actual value of the 132 lbs. in the manure would probably be greater than that of the 138.2 lbs. in the bran.*
364. Plow Under or Feed.—The same principle will in some cases determine the question whether it will pay better to plow under a green crop or feed it to stock and return the manure. If on an acre of land there is a crop of clover that will make two tons of hay, it will contain plant food worth $17.52. If the clover is plowed under, this is all the value that will be obtained. Ifitis cut and fed to fattening cattle and the manure carefully saved and returned, the loss of plant food will be only 88 cents. The ques- tion of profit and loss will therefore be on the one hand the value of clover as food; on the other, the cost of cutting, curing and feeding the clover, and of saving, hauling and spreading the manure, and the 88 cents’ worth of plant food lost.
*It must be remembered that all such calculations as these are based on the supposition that al/ the manure is saved. Where the liquid manure is allowed to escape and the solid portion wasted by leaching and evaporation, such calculations will be very wide of the truth.
166 SCIENCE IN FARMING.
Any farmer, therefore, who can determine these points, namely :
The feeding value of the clover, The cost of cutting and curing, The cost of hauling and spreading manure,
Can readily determine whether it will pay best to plow under a crop of clover or feed it and return the manure.*
§ 7 Valuation of Manure.
365. The determination of the comparative values of different makes of commercial manures can be ac- complished with reasonable accuracy, but the com- parative values of farm-yard manures can be deter- mined approximately only. They not only vary ereatly in the amount of plant food contained, but the value of that plant food differs according to the form of combination in which it may exist. A pound of nitrogen contained in urine is available for the plant, and is as valuable as a pound of nitrogen in nitrate of soda, or sulphate of ammonia. But nitrogen con- tained in half-digested straw is but slowly available, and may remain in the soil unused for years.
366. For convenience the experiment stations of this country have adopted certain figures to represent the market value of nitrogen, phosphoric acid and potash.t
*We have seen (171) that clover when plowed under may by the production of humus, serve other useful purposes in the soil besides furnishing plant food. In all cases where more humus is needed to improve the condition of the soil, a new element enters into the calculation of the comparative profit of feeding or plowing under. In such cases it will doubtless often be more profitable to plow under until the improvement in the condition of the soil has been accomplished.
+The mistake is sometimes made of supposing that these figures represent the value that these substances will be to the
FEEDING. 167
367. The valuations adopted by the Ohio State Board are:
Kind of Plant Food. Price per lb. PURGE er ee we le a a es 18 cts. Whichusequal to mitrogen..:.. 2.0... .g.4 2.0.6. 21.86 cts. Phosphoric acid in soluble compounds ........ 125 ete: Phosphoric acid in compounds insoluble in wa-
ter but available as plant food .............. 10%, ets.
Phosphoric acid in insoluble compounds which
have to undergo decomposition in the soil be-
fore they can be used by the plant .......... 5a! Cte: Potash in soluble compounds... 2.0. ....0... 2, 6 ets. The phosphoric acid in soluble compounds is called
in the official analyses ‘“‘ soluble phosphoric acid.” It is principally in the form of monocalcic phosphate (110). The phosphoric acid in compounds insoluble in water, but which can be used as food by plants, is called “reverted ;” it is principally contained in bi- calcic phosphate (110). The phosphoric acid in in- soluble compounds is called ‘insoluble phosphoric acid,” and is principally contained in tricalcic phos- phate.
In the estimation of the value of manurial constit- uents in farm-yard manures, we shall adopt the fol-
lowing standard: PLANT FOOD IN MIXED MANURES.
PURE ARE RAN re Po OS, te x any ogee ae sends tees 15 cents. MOM AO TUE CUCU DN? Soo: Yies cope o Rises ce tarde slate Db wad oN 8 cents. 120 STOR DENTE RSE eA OE OR Ae RC ORO ne OP aR 5 cents.
farmer when applied to his field. No general estimate of this value can be made, as it depends on soil, season and circum- stance. A hundred pounds of nitrogen applied to the soil might in some cases be worth to the farmer a dollar a pound, under other circumstances it might not be worth a dollar for the hundred pounds, or might even prove a detriment. There- fore when the statement is made that nitrogen is worth 22 cents a pound, the meaning is that it can usually be bought in the market for that price in forms that are immediately and en- tirely available for plant food. Whether the nitrogen will be worth that amount to the farmer in every particular case must be determined by other considerations.
168 SCIENCE IN FARMING.
PLANT FOOD IN SOLID EXCREMENT.
NabrO memo o/s ES eae ote 10 cents.
PHOSPROLic ACG, :.. ieee ON, ca oe eh 6 cents.
OUABIS oe 203/54. «eR ate eos eae 4 cents. PLANT FOOD IN URINE.
NOU PO RCI ini tte nL Re 22 cents.
Phosphoric acid’. jean ee: lie. ot ae nee 12 cents.
PO basic ee, ne ee eat Pen eC 2 Ss She te ea 6 cents. PLANT FOOD IN FOODS.
INGER OR EIT PA Aiko ted eh Rtn, Cake Nes ha te 15 cents.
PHOSp Orie Held Ge bys. ols cleiiaed chem, 8 cents.
Grainne! sewer hor oi bad: co Sie lela a ee ee ee 5 cents.
368. Plant food in ordinary barn-yard manure is not worth as much as in nitrate of soda, sulphate of ammonia, superphosphate, etc., on account of being in forms that are less readily available to the plant. The constituents of urine being already in solution are of the highest value. The determination of the value of the manurial constituents in foods is a mat- ter of difficulty and one in which strict accuracy is impossible. The more digestible the food the more valuable are the manurial constituents it contains. Therefore in the table in paragraph 372 the estimated value of poor and indigestible foods is liable to be too high, while that of rich foods is probably below the truth.
369. Tables of Values of Farm-Yard Manures.—These tables represent approximately what the same quan- tities of nitrogen, phosphoric acid and potash in equally available forms would cost in commercial fertilizers:
VALUE OF | TON FRESH FARM-YARD MANURE.*
Nubregen: Oe mu sy SU ie 9 Ibs, @ ~ 15'cents $1 35 Phosphorieacid.../.2 2). 4.2lbs. @ 8 cents 3 P@tAsh 35: hy etingc, Mees 10.4lbs. @ 5 cents 82
otal wealate pon os see ee eee $2 21
*As usually found in the barn-yard; composed of the mixed excrements of different stock with the straw used as litter.
FEEDING. 169
WELL ROTTED FARM-YARD MANURE.*
INIERORER ee ye ei4 weiss es «+ 11.6lbs. @ 15centst $1 74 Phosphoric acid 4.9.54... 6 lbs. @ 8 cents 48 Potash. Sa eae es ae. oa 10 lbs. @ 5 cents 50 fT al on 15) a er eee ee rere e272 FRESH HEN MANURE.} WVGLPOREN 22s wie le os +8. 32.6 lbs. @ 15 cents $4 89 Phospuoric acid... ...<. 30.8 lbs. @ 8cents 2 46 Mek ek kes ahs as 17 lbs. @ Scents 85 iste Wale OF lotOn Mic Se hee ele ee ee $8 20 AIR DRIED HEN MANURE. PNTENOROM 25 52. gen d's hes 65.2 lbs. @ 15 cents $9 78 Phosphoric acid.....:.<. 61.6 lbs. @ 8cents 4 93 Re mate ER Sis, earls ecersrae eran 34 Ibs. @ . 5cents 1 70 Sisal ont iadnGS. HOLOUIEIC «cc ictal e ecco eae © pee ees BE $16 41 FRESH SOLID EXCREMENT, HORSES. MUGPOPON S25). 5 ol a Se en 8.8 lbs. @ 10 cents $ 88 Phosphoric’ acid:......-. 8.4lbs. @ 6cents 20 eee ete. eet as 7 lbs. @ 4cents 28 Watak Value: OF L GOMM.:<)., oud AB swe Seo: Hoel Se $1 36 FRESH SOLID EXCREMENT, CATTLE. RPPORBIN fo. ia's pos «oe « -:e 5.8 lbs. @ 10 cents $ 58 Phosphoric. acid... -.:... 3.4lbs. @ 6cents 20 WIE Ae lc healer a onl oes 2 lbs. @ 4cents 08 Taraliwalae of One tO es ck se heise bee $0 86 FRESH SOLID EXCREMENT, SHEEP. ITGROSOTE fyo5 os, cscs ars apse 11 lbs. @ 10 cents $1 10 Phosphoric acid. i... ° 6.2lbs. @ 6cents ot WPEA Sie ho ste ee HE adh he 3 lbs. @ 4cents 12 Tatalivnlle GtONne TOM Acs ic. so esie ew ae oe $1 59
The manure from which this analysis was made must have been rotted in an open yard, and exposed to waste both by leaching and evaporation, otherwise it would show a higher value in proportion to the fresh. It is however, probably a fair representation of the rotted manure that will be found in most barn-yards.
+If the nitrogen in the fresh manure is worth 15 cents a pound that in the rotted manure (if fermentation is properly con- ducted) is worth more.
+Manurial constituents in hen manure are probably more soluble and therefore really worth more per pound than in the mixed farm-yard manure.
170 SCIENCE IN: FARMING.
FRESH SOLID EXCREMENT, SWINE.
INIGFOMEN GC ics ae aac aamee 12 lbs. @ 10 cents $1 20 Phosphoric acid......... 8.2lbs. @ 6cents 49 Potash Be gitar mae Cac iy 8 a 2.6lbs. @ 4cents 10 Total value-of one toner, ee 2 Se $1 79 FRESH URINE, HORSES. NTEPOR@ OM ili. Ree eae ola ibs. @ 22 cents $6 82 H E052) <1 6 Dra aeaamlgpat ess AN HS 30 Ibs. @ 6cents 1 80 Petal valve -Of OMe OMe meg as) aired. «a Wsk Naoma ile $8 62 FRESH URINE, CATTLE. INGLFOGER 22. rattan s 11.6 lbs. @ 22 cents $2 55 TO base O tidieaes tote Bhi ie 9.8lbs. @ 6cents 59 Total value, of One TON O22 Gi ae $3 14 FRESH URINE, SHEEP. NIETO ROTA Sota e 39 Ibs. @ 22 cents $8 58 Phosphoric acid......... 0.2 lbs. @ 12 cents 02 POtashiys ose ee ers 45.2 lbs. @ 6cents Zo 7A Total, valve of one ton. ia. 5. te eee ae eee $11 31 FRESH URINE, SWINE. Niko CEM heh eA as 8.6 lbs. @ 22 cents $1 89 Phosphoric acids oe! iesic: 1.4]1bs. @ 12 cents 17 POLAR hase ue we ee tee es 16.6 lbs. @ 6cents 1 00 Total value‘of one tonic. 4 fo ee ae ee eae $3 06
370. These tables should have careful study. Farmers who allow their liquid manure to drain away but carefully preserve the solid may be surprised to learn that while a ton of the solid excrement of a horse is worth only $1.36, a ton of urine is worth $8.62.
It is true that these figures represent only the com- mercial value of these substances, and not their value when applied to the soil, but the proportion will be correct, even if the actual value differs. Thus if a ton of solid horse manure under certain circumstances is worth to the farmer one-half more than the figures given, under the same circumstances a ton of the urine will also be worth one-half more than the figures given. If under certain circumstances the ton of urine is not worth $8.62, then, under the same
FEEDING. 171
circumstances a ton of solid will not be worth $1.36.*
Urine being rich in nitrogen in a form that is im- mediately available, renders it specially valuable as a top dressing for crops requiring this substance.
371. Valuation of Foods as Manures.—The knowledge of the manurial constituents of foods and their value, is of considerable practical importance, as it has much to do with the profits of feeding and the choice of foods. Two foods may have equal feeding value and cost about the same, but the manure produced from one be worth more than that produced from the other. By knowing the feeding value of each. food and the value of the manure produced from it, a farmer can often make a calculation whether it will pay to sell some article of food and buy another.
The question is often asked whether it will pay to sell straw, the opinion being held by many thata farmer who sells straw will impoverish his farm. By reference to the following table it will be seen that the plant food in a ton of straw is worth $2.44, while that in a ton of bran is worth $13.25. Then if a farmer can sell straw for $2.44 per ton and buy bran at $13.25 a ton, there would be no loss as far as elements of fertility are concerned. There would be in facta slight gain, as the plant food in the manure produced by feeding the bran would be in a more available condition than that in the straw.t
372. Sir J. B. Lawes, of England, many years ago prepared a table giving the value in money of the
*An exception to this rule may arise from difference in the character of the two manures. Urine is rich in nitrogen and potash, but contains no phosphoric acid. When this latter substance is the one needed by the soil, the solid manure will have the greater proportional value.
tIn this we have considered only the value of the plant food
172 SCIENCE IN FARMING.
manurial constituents in different foods. Since its publication this table has been the standard in this country as well as England. The following table is calculated on the basis of valuation given in para- graph 367, and differs slightly from that of Lawes:
AMOUNT AND VALUE OF MANURIAL CONSTITUENTS CONTAINED IN ONE TON OF DIFFERENT FOODS.
Pounds Pounds Phos- Pounds
Name of Food Nitrogen phoriec acid Potash Value. Linseed cake.......... 90.0 39.2 29.4 $18 10 Cotton cake, decorticat-
(2) yt SAA a ett teal ge a a: 132.0 62.4 30.0 26 29 Cotton cake, undecorti-
CHLOG sc a te Sere a 78.0 45.8 40,2 ikfaae Beans we) act cee os 82.0 23.2 24.0 15 36 Peas Cie) Ss tates eae 72.0 17.6 19.6 13 18 Pirate ee aa ee cee 44.0 64.6 29.6 13 25 ROLE etc dnits ee acess re tae 41.2 12.4 9.0 7 62 Barley aie ornare Ges. stent 34.0 14.6 9.8 6 76 Indian: corniss3:440 5.5 Bas 12 T2 6 32
HAY AND STRAW.
Clover hays eo. 228: 39.4 11.2 39.0 8 76 Meadow hay: ...:..... 31.6 7.6 33.6 6 94 Wheat ‘Straw. 020 ¢ ca. 9.6 5.2 11.6 2 44 Barley straw. J... 03 .. <. 10.0 4.0 19.4 2 79 Ostatraw.Aiorsevcas es 10.0 5.0 20.8 2 94 Pea straw, cutinbloom 46.8 13.6 46.4 10 28 Pea straw, ripe........ 20.8 7.0 20.2 4 69 Cofnstallis oc? 22 ieee: 9.6" 10.6 19.2 3 25 GREEN FODDER. GLASS ee ce ee Bea 10.8 3.0 92 2°32 edi clover 235-3 10.2 2.8 8.8 3 37 Peas ths oa see nS 10.2 3.0 10.2 2 50 Oat rive meee wae ee 7.4 3.4 15.0 2 ae Eye irchars uta oe ee 10.6 4.8 12.6 2 60 WOT on mos eae hee ee 3.8 2.6 8.6 1 2k Hungarian... ee oe. 20.0 2.5 17.0. 5 pana SOK eM ha Me ork ws bak 8.0 1.6 7.2 1 69 ROOTS | 6.12117 0) OM vane ee cas 6.8 3.6 11.2 1 87 Mangele..G iat ocak: 3.8 1.4 7.8 £207 SUITE Aleit ae tas eed oe 2.0 6.4 96 fii oi 7 Ren ane or 3.6 1.2 5.8 5 77
373. From this table and the rules laid down in
contained in the straw. When straw is used as an absorbent,
FEEDING. 173
paragraph 361, a farmer can calculate the value of the manure produced by feeding a given quantity of any kind of food to any class of stock,
Thus, a ton of hay with half a ton of corn meal, and 500 Ibs. mangels contains plant food worth $10.62. If this were fed to fattening oxen, 95 per cent of the plant food would be contained in the manure produced, which would therefore be worth $10.09. A ton of corn meal fed to fattening cattle would produce manure worth $6.00. Fed to fattening pigs the manure pro- duced would be worth $5.37. Fed to milk cows the manure produced would not be worth more than $4.74.*
§ 8. Commercial Fertilizers.
374, The use of commercial fertilizers has greatly increased during the past few years. Their composi- tion is often very uncertain, and in localities where there is no efficient fertilizer law in force, they should be purchased with caution. In Ohio and some other states the manufacturer is required to print the analysis on every package, and a heavy penalty is im- posed if the composition does not agree with the printed analysis.
375. Bone Dust.—This is bones reduced to a powder, and when pure the composition is the same as bones. One ton contains:
ISI CER2 ae cera ee giant Deer Sk ot a a pe ee 76 Ibs. ESP EIC CUR eo, Se ets Asis ele poms oak Oe wt 364 lbs.
The phosphorie acid is in the form of tricalcic phos-
and prevents the waste of liquid manure, it has a practical value greatly in excess of the plant food it contains. Thus, if a farmer sells a ton of straw, and in consequence of the lack of sufficient absorbents allows a ton of horse urine to be wasted, the total loss, direct and indirect, would be $11.06.
*All these calculations are made on the supposition that none of the manure produced is wasted.
174 SCIENCE IN FARMING.
phate, and is therefore not available as plant food until it has undergone decomposition in the soil. Grinding the bones by increasing the amdunt of sur- face exposed (164) facilitates this decomposition, but the action is comparatively slow, and the effect of a dressing of bone dust is spread over several years. On account of its insolubility, bone dust may sometimes be used with advantage on soils that possess but little power of retaining fertilizers.
376. Guano is the excrement of sea fowls, that has in some places been accumulating for ages. It is principally obtained from the islands of the Pacific. The valuable constituents are phosphoric acid and nitrogen. That which comes from countries where no rain falls, contains a large amount of nitrogen, some- times as much as 240 lbs. to the ton. Where it has been exposed to rain the nitrogenous matter has been mostly washed out, and little but the phosphoric acid remains. Phosphatic guanos are often converted into superphosphates by treatment with sulphuric acid.
Owing to the uncertainty of its composition no analysis of guano can be given that would apply to more than one sample. It should always be bought on the analysis of the particular brand.
377. Rock Phosphate.—Large deposits tricalcic phos- phate are found in some places, (110) and are called “rock phosphate.” These deposits are the remains of marine animals. The organic matter has wasted, and the calcic phosphate of the bones become com- pacted into a mass like rock. This is ground to a powder, as fine as flour, and in this condition used as a fertilizer. It is most valuable on soils rich in humus, as the organic acids they contain assist in its decomposition and solution. It is also rendered more
FEEDING. 175
soluble by composting with barn-yard manure. It contains no plant food of value, except phosphoric acid. Rock phosphate is often converted into super- phosphate by treatment with sulphuric acid.
378. Salts Containing Nitrogen.—Those in common use as fertilizers are the sulphate and chloride of am- monia, and nitrate of soda, (108, 109 and 115). They are valuable only for the nitrogen they contain. Be- ing entirely soluble they act very rapidly and will give nearly all their effect the same year they are applied. Lawes and Gilbert found that 45 to 50 per cent of the nitrogen in these salts was recovered in the increased crop the first year, when applied to wheat and barley ; but that the following year showed very little effect from their application.
Owing to their solubility these salts are very liable to be washed out in the drainage water, if applied at a season when the crop cannot make immediate use of them. They are best applied as a top dressing in the spring.
379. Superphosphate.—The composition of super- phosphate and the principles of its manufacture have already been given (111). Commercial superphos- phate is a mixture of monocalcic phosphate with gypsum. It also usually contains some free phos- phoric acid, and bicalcic, and tricalcic phosphate. When prepared from bones it also contains a consid- erable per cent of nitrogen. To increase the amount of nitrogen, blood, shoddy, leather waste, and the refuse of slaughter houses are frequently added. The character and composition of any particular brand can only be determined by analysis.
Many of the commercial superphosphates contain a large per cent of nitrogen and potash, while others,
176 SCIENCE IN FARMING.
especially those made from rock phosphate contain only phosphoric acid.
The advantage of converting bones and rock phos- phate into superphosphate is due to the greater solu- bility of the monocalcic phosphate. No plant food is added by the process.
380. Manufacture of Superphosphate.—The princi- ples of the manufacture have already been given (111). In practice it will rarely prove profitable for the farmer to manufacture his own. The proportions would be, theoretically :
B16) 002): PNY ee es bie SSO ane CMR eMTRL yy} cyt 100 lbs. Sulphuric acids: 7 656 cs edad ee eee 35 Ibs. Water. 54S cco asc t: uses Varta ee oe 13 Ibs.
Which would produce 148 Ibs. dry superphosphate. In practice, several times as much water would be needed to make it possible to mix the mass. The bones should be put in a wooden vessel, and the water poured over them. The acid should then be added, a little at a time. If all the acid is added at once the mixture will be so strong that it will be liable to de- strey the wooden vessel. Therefore time, between each addition of acid, must be allowed for it to com- bine with the bones. The decomposition of whole bones by sulphuric acid is a slow and tedious process.
§ 9. Adaptation of Manures to Crops.
-381. Different crops require very different supplies of food. The table in paragraph 331 shows the amount of different manurial ingredients removed by different crops, but the proper manure for each crop cannot be determined by such a table. Thus, it will be seen that acrop of clover removes from the soil. more than twice as much nitrogen as a crop of wheat, and yet wheat specially needs nitrogenous manures,
FERTILIZERS. 1
while clover does not. The reason of this is some crops have greater ability to obtain certain substances from the soil than others.
It was formerly taught that all the constituents of plant food contained in a crop must be added in the manure. This is no longer considered necessary. If each crop is manured with the particular substance most needed for its successful growth, and a judicious system of rotation followed, the best results will be ob- tained in proportion to the manures used, and no un- due strain will be made on the capabilities of the soil.
382. Cereal Crops.—These crops, in general, are spe- cially benefitted by nitrogenous manures. In the ex- periments at Rothamsted it was found that from forty to eighty pounds of available nitrogen to the acre se- cured a maximum crop. Potash is usually of little value. Phosphoric acid when used alone seldom pro- duces much effect, but is beneficial in connection with nitrogen.*
383. Indian Corn.—No satisfactory experiments have yet been made to determine the best manures for corn. Phosphoric acid appears to be beneficial in many cases, and when combined with nitrogen, good results are usually obtained. Land plaster is a fa- vorite manure for this crop.
384. Grass— Requires all the elements of plant food, and well rotted stable manure applied as a top
*It is the opinion in many parts of this country that phos- phoric acid is the manure specially needed for wheat. This opinion is probably due to the fact that throughout the West the superphosphates used have been mostly prepared from bones, and contain nitrogen, often in considerable quantity. The general result of experiments with purely phosphatic ma- nures are that, unless combined with nitrogen, they are seldom of much value for cereals.
12
178 SclENCH IN FARMING.
dressing to old meadows or pastures supplies this need. Bone-dust is also especially valuable for this crop, and can be sown broadcast.
385. Clover.—Although clover contains a: larger - amount of nitrogen than almost any other crop grown on the farm, it does not seem to need nitrogenous ~ manures. Potash and lime are the most valuable manures, the lime being best applied in the form of land plaster.
386. Turnips—Require nitrogen and phosphoric acid. They seem to have little ability to appropriate the phosphoric acid existing in the soil in insoluble combinations; hence fresh applications of superphos- phate in connection with farm-yard manure have a remarkable effect. In England superphosphate is chiefly used for turnips, which are one of the most im- portant crops grown there. Nitrogen without phos- phoric acid will not secure a full crop. :
387. Mangels—Obtain much less benefit. than.tur- nips from phosphoric acid, and require more nitrogen. Mixed farm-yard manure is suitable.
388. Potatos—Are similar to turnips, giving best results from use of phosphoric acid and nitrogen. In soils deficient in potash this is an essential constit-— uent in the fertilizer used; but soils that have been manured with farm-yard manure usually contain sufficient potash.
§ 10. Summary.
The problem of maintaining the fertility of the farm can only be satisfactorily solved by a considera- tion of all the principles taught in this chapter.
The farmer who drains and cultivates, but fails to restore to his land, in a measure at least, the elements
FERTILIZERS. 179
of fertility that have been removed in the crops, will, sooner or later, reduce the amount of available plant food in his soil to such a degree that the production will be seriously decreased. |
The farmer who carefully saves all his manure and returns it to the soil, but pays no attention to drain- ing, and but little to cultivation, who allows weeds to grow and rob the plants, will probably complain that manuring does not pay—for no amount of manuring will secure good crops on soil that needs draining, or where the proper mechanical conditions are nop pro- vided.
The farmer who builds his barns and stables on a side-hill, allows all the liquid manure to escape into a
ereek, and keeps the solid portion where the drip- pings from the roofs will fall upon and leach through it, will be very likely to reach the conclusion that manure is of little value and will not pay for hauling to the field. And his conclusion will probably be correct with reference to the manure he uses.
It has been shown (160) that when a judicious rota- tion is followed, a good proportion of the crops fed on the farm, and all the manure carefully saved and re- turned, that the drain upon the soil will be but small.
It would seem, in fact, that under such circum- stances, there is no need, at least at present, for pro- curing plant food from sources away from the farm. The farmer is not required to make provision for con- tingencies that may arise from seven hundred to three thousand years hence. If he uses care and judgment, he may not only produce on his farm the material needed for maintaining the fertilitity of his soil, but, by rendering soluble the plant food it already contains, actually increase its fertility. It should be ever borne
180 SCIENCE IN FARMING.
in mind that it is not alone the amount of plant food in the soil that determines its fertility, but also the forms of combination in which that plant food exists.
Most soils contain a great amount of plant food, and hence treatment such as drainage, cultivation, lime, fallow, and green crops, which do not add plant food, but only change the condition of that already present, are often successful in changing a compara- - tively barren soil into a fertile one. And if, after fer- _ tility has thus been obtained, the greater part of the crops grown on such a soil are fed on the farm and the manure produced returned to the soil, the fertility may be long maintained without the addition of plant food from sources outside the farm.
If, however, it is desirable to rapidly bring a poor soil to a condition of fertility, there can be no doubt of the value of commercial fertilizers, as these will enable the farmer to grow large crops with which to make much manure that can be brought back to the soil.
When the farmer wishes to make the growing of grain, to be sold off the farm, his principle business, the use of imported fertilizers will sooner or later be- come a necessity.
In many cases one of the most economical methods of obtaining plant food from outside sources, is to buy bran, linseed or cotton seed cake, etc., and feed it to stock, carefully saving the manure.
ENDEX.
Numbers refer to Paragraphs, not to Pages.
A ASH ETS Ty bie A Ae pe ae RCRD BEE 93 AICI Se TAME EG ts Oye Si a oe 101 Amides ........-........ esses, 5 La OR ES Aer eer eae 138 cannot be changed to albumi- DHOSPNGOVIG) ct ses we AE ee 100 noids ....-............ NS Fes 226 Pee ete hes 103 often classed as albuminoids 225 pai mbninie . 109 proportion of in different food . 240 ee a SS ee) 102 Ammonia, absorbed by soils ........ 153 Acids and alkalies distinguished ... 63 ubtorides. Beer US bap er Memb ee ; oe Acids, definition of .................. 62 er ULE caagion (ofan he gts A ETETELGH OSE) RN SR a ae ei me etl 124 contained in air .............. 138 Agricultural plamtss../.:...-¢.2.a0 * 166 ae aaah ari Unt aete Saher as 8 ie Adhesiveness of soils ................ 154 evaporation of, how prevented. 345 Affinity 59 forhouse plants 12... e402. 2 Os Ar COMPOSITION: 05..5.)..0 eet oe 133 quantity of inair............ a fitocminy OLE Rs ooh ee 134 retained in soils.............. 153 dried in a stoveroom............ 141 source Of Im air.-............+. a ho Wwawermed teas) cca men ae 52 sulphate... .... ..........-....-. 378 what the farmer gets from...... 143 SS ne the household... :..-..... " eee cone hs iat 197 ATI ONIC'CALDONALG, «. se ense eae. 112 AibaMUNoid Tato - 3 ...0200.65 5. 255-264 vena Pi Sap aurea rene cach ake Hy error in caused by amides 256 SERRE PON ge eect om for fattening animals............ 297 Seely pis of soils, value of) --.. et farsaalk 291 Animal cannot use inorganic mat- RE Ses ME Pee A I ‘ for workinicanimale: sata ter.. Gig ak: bc Bea Jace 203 EE SES Np eee 284 composition: Of 7. i... cen 2 198-202 Geandenadists 960-262 matter compared with vegetable 202 A utd a 4) «: oA7-258 Animals, the farmer’s machine. 267-270 Fort ESSAY ORG vay Se manent 126 Annual, process of forming seed.... 192 decrease in plants as seed forms 192 aia teaniy cs Loree Li l Gr Fees effect of insufficient in food ..... 218 ri <li ra heise pn sh Ree a 905 hich value in some cases _ 248 ssimila ion. tee ete eee eee eee eee: 2 : ere ade oer Re rereg 187 ATOMms ACGHNITION- Of ents oct 18 meet all needs of animals........ 210 Atomic oie Pewee a cee eG rhb - oxydized in circulation...... . 207 er ha hed As teed ace ae aa TOLMOM OW UNOU. ce hh es ese nee 225 i APPR Caton GBs oe: fe aes Sire s B used for repairing animal Beer ee ae eer ene RE 2 hO.NG) Sr 163 used in making new tissue...... 213 definiti 9 etl a ie 249 Basesvdeinition toss seta see 6 ee pee ae F ‘Bicaleie phosphate. so-. 5. ce helen cee 110 Aftermath hay, analysisof.......... 293 ies 3 ‘ - 1 ANaloids 129 TOTUNTAIS! 5 ib ok otos cl ciehe ae come hes wee 93 ik eh Nika neal eh eek Viel black leads nature. of... 4 eee ee *Will be found in foot note, (BORE GUSh iis). pct. homage tae miarranes 378
182
Bulbs, storehouse of food ........... 194 Burning putters eee ee 272-273 Cc Calcareous soils, how known........ 112 Calcic, carbonate <3). cee ee 112
OXIDE ee ee eee ee OF Caleiim (022 yea cae eRe eee 92 Capillary attraction ................. 150 Carbohydrates oa. ce a eee ee 118
do not exist in animals.......... 199
Wale Of MsitOoduasas war ween sae 249 CaRbon nce erence eet eee oe 88 Carbonate of ammonia .............. 112
OPA tee ter See Nake pees Sarees 112 CAEDON AEBS. cate ccc ceisae Sucker 112 Carbonic dioxide, amount in air.... 99
COMPOSITION sey eae eee 99
contained in spring water....... 99
NO WaplLOduUGed es aA eee 99
iMicellarOn pice sees ee eae 136
IMGhaATdswaterenalnas asserts 99
needed byaplants! tas. ceeee een: 99
POISONOUS tas cet oe ee 99
QuUantity.OL AMA esc. se se ee 139
removed by lungs............ 207-208
supplies carbon for plants....... 139
taken up by roots of plants...... 186
Carcass, proportion in increase. .311, 312 15 of live weight .. 313
Capeine tice eee orn eer eae 127 OBRtAIY RISING ties Met ee ont ReEe eo. 122 Ceallnloseas pam eas coer or eati an howe 119 Cereal crops, manure for............ 382 Character of food, meaning of term* 238 Charcoal) nature of 292.0. .0s22.ece 88 Chemical combination............... 57 FORCE as ws oes blk Coe aan eee 59 BY IM DOIN se. seer glee ee ee 80 Chemisimy eerie het er ee 59 Chemistry, its nature................ 56 of carbon compounds............ 114 Chemistry, agricultural ............ 11 value of to farmers ............. 10 Chilisalipetre sian stents .cicrseeorae 108 Chiorideammoniaiic. ocean 113 Chiorphyl ss ioke eel eae ee 187 CHIOLvIMNG 5.4 eee een he Re ae 87 Clay, characteniotissen. nc chicane 170 offectio£ LIMGION seca sske ate 170 origin and composition.......... 146 soils, how improved ............. 176 Clouds, protect from frost........... 54
SCIENCE IN FARMING.
Clover, injured in curing............ 236 PHAMTOS TOL). 2)... 2.0... 2 eet ee ere 385 plow under or feed............... 364
Woldsottect.Of ...: is eh asseeaeee 2228 effect of in feeding ............... 273
Colostrum, analysis of.........::.::. 280
Combining proportions.............. 72
WOMMUSELON \3:-.52'-:sccct cc aes See 131
Compounds, how described.......... 82 how represented.......:.........- 81 proportion of elements in........ 96
Conduction, difference in............ 42
COPPeLAws scan, ea sks eRe cee 109
Corn, not a complete diet for pigs.. 309 Crops, require different manures ... 381
Crude fibre, meaning of ............. 228 Dark soils, absorb warmth.......... 152 DOGRY. ee ures & Shade eR ee eee 132 Decimals, definition of .............. 30 Dew=point e205... 2. kecs hic. ae eee 140 Dew, why none on cloudy nights.... 140 DORtTING |. i cls. Sees eee eee 120 DeEXtTORC iz .56 6.6 uk ae ee eee Tala, Diamond, nature\of. ..0. 4-4 ee 88 Diffusion ol Gases)... .2. eee ore 135 Digestibility of food, affects its char- acter’). sic aie see eee eee 238 of food affected by mixing... 244-247 oS ape ‘. SOMA unity. cca 243 $6 068 GTR oo teen eee 237 Digestion ceo5s ec oe eee oe 204 most perfect how secured........ 247 Disinfectant, copperas.............-. 109 Division, Ciectiok. ec... 7-4- eae 164 Drainwee,etlectiohs.. 4-24-41 es neces 166-168 Warme the soil 422. nace 50 Drought, prevented by drainage.... 168 Dry soils, become warm quickly.... 152 Dry substance, meaning of.......... 179 E Element, definition of ........... ee el Elements, list of agricultural....... 83 Energy, animal, source of........... 211 Original SOUTCE Of! eo. 37 Equivalents ....... Sire. sbylich yak Oe Eee 78 WINE@MACAUSIS .2 6 smc se eee eee 132 Excrement, solid, undigested food.. 208 MIR CTOtION: a 058s aw ae eae eee 208 Hxercise, effect Of 6. «4. 22a eee 221-223 effect of in feeding ............... 272
* +Will be found in foot note.
Numbers refer to paragraphs, not to pages.
INDEX, 183 HWxHaietiony OU SOUS acess... 159 | Food required to make 1 pound iM TrObaAtlONe te eee ets en 160 INCTLOASOS cn. od eect ete 299-302 F surplus how disposed of.......... 214 Fallow, LOE U2 htc; Be ee eee ne era ee 326 table of composition ............. 230 Farmer, a manufacturer........... 6 undigested how disposed of...... 217 need of knowledge .............. 7 used for production of heat and may prove injurious ............. 326 ONOREY <i baci Sere ete ce eestere 212 Mat how MiSeSbeds onstees eae carne - 204 uses of in animal body....... 209-211 how producedin plants ....... _ 187 valuation, comparative...... 248-254 not changed into albumin....... 210 valuation of manurial constitu- produced from albuminoids ..... 213 ENGR TD Ree asec ae alerted eri 371-372 mradnetion Of... . 0... -0ccces-e 214 value of not determined by anal- rule for reducing to value in car- VBIB ows een ete neeeen yet aeeene’ 237 bohydrates ................. 950-252 | Force, definition of ...,......-....--- 19 used for production of fat ....... o15 ; Formula, chemical................... 82 . valueofas food 22) we ttc. :eeee.. 249 | Free, meaning of term.............. 70 MR ae een _ 125 | Fungi, how they feed. ............. * 187 ¥attening animal, composition of G MMCHOARCET Ces oie eee ee DORM PASS avtakisind Geis oe ieee ueetier emacs 17-18 animals, variation in rate of in- Geelartinnsc ys vee at Sic ee pact 127 CEGRARG ete Leche eee 306 | Germination, chemistry OR 183 Experiments iM 61: ooh. ceas lo: 295-308 general summary ..........-...-- 195 Fertilizers, commercial ......... 374-380 MECESSITIES {ON eects ene eae 184 HOliNInLONG fo eee ae 317 ) temperature required for........ 184 Feeding, effects of coldin........ 273-275 G pee ae ig CORES Sea alan ey hake oo At a effect of exercise in............... 272 Glut Ole Ce oer a rope rae ee general principles of......... 265-279 rr tee erie nega ce tae ane ; : : : = Grass manure Lory vores estes: 384 objects to be attained in......... 265 i eae; 4 ; a: : Greenmanuring-o.c-e es eo: ee 328 Ferric oxide, retains fertilizers..... 151 Goan sos Fertility of soil, affected by its fine- EES NPT aR eet F (OATEIST Te} CA Ren Steep neh ERS es ncieinlaga Peete 121 LORS Rt alg Unseen mareues Pee 164 ee as eying as An ee aid ected 9 ROE ee: Se aes on aes ‘ Reena Gala 125 Use IN’ MaNure.......... 2.6 ses 109, 345 Flesh formers, use of term.......... 229 - ; Food, adaptation of 97] Hay, effects of methods of preparing 23 PAC ADUDtILOMY Of... 5 isa 6 sia crayeiest 2
best for young animals....... 280-284 comparative value of 254 composition affected by soil and
BEASOM str sae years aitemink sein ots 235 COMPOSITION Of. 3s. saree ssc 230-236 consumed for heat and en-
ONG Vere erie, he cooiues sles ea Ue GISesIDMTLY OL. -pokias) ae eol— eal, GISHOSLULON Of. 22 $855 20.0. ee ae 212-217
for producing milk 285-294 for fattening animals 295-298 insufficient, effects of........ 218-220
must contain all elements used
[anieneNr Ub ee Ce LN Maley aa es ie iene eile ey 210 Ol-w hat, COMMOSCO. | ici csecen sels te 224 pounds of digestible constituents
in ton 239
Fe eee eee ee eee eee yee
composition affected» by date of CUtTIN Gee eke ose Se see Pe Sys
Heat. absorption of 4.034 +. eee 46 animals SOUTCE Ofte 2c ettaton oe ee 211 cannot be destroyed.............. 37 Conduction: Of-- 2. vee see 41 CONVECULOMMOee ase one 43
excessive cause waste in feeding 275
needed for melting ice ........... 34 needed to boil water ............. 34 OLIFID OF se cenc Oc earache he 38 produced in freezing............. 36 produced in slaking lime ....... 35 producers, use of term........... 229 PLOtECtion {LOM soap bees eet 48 TACIAtOM Offs 2 baieiocrs cts suntan 44
*Will be found in foot note,
Numbers refer to paragraphs, not to pages,
184
Heat, same principle as energy.... 32-36 SNORING ae nom orem Wes 39 transference of- i... 2... 40-46
Horse, digestive power of ........... 241
Horsefall’s experiments in? feeding
GOS seeking yn Aas creniye hs es 294
How the plant grows ........... 185-190
Humus, power of retaining water.. 148
to estimate quantity in soil ..... 171 OLIPIMVOL EH a aes Ar alia any 146 retains fertilizers. oo... 45k 151 Waluelor-im SON s..088 ke ee 171 Hydrogen.......... Eee aes 85 Indian corn, manure for ............ 383 PPI OSs Fem aes te ten eee. i Terai 120 1 Uy eta boa a ete cae ea ent a fo HLM Sep 94 DlACK ORNGGt esos hoes ate eee 94 in soils, how rendered harmless. 94 TEGOXideeew esos eee eee 94 when injurious in soils .......... 94 ESOMELISMIA Ae otek ree ee 116 L WigevayOse ese s ts ae as WH ar Se 122 Dramdplan tery i277 ee eee es 109 Leaves, effect of removal......... .. 189 exhanstioninitalls....0.4. 3. 189 WORKIOF PAM a eerade Ron dn ier eMac 187 LIME, As IBANUTe soso eee 327 eect onvammoniai aye 107 ODVCLAY SOUS bese seas oscar Cine ake 170 CRTC ets a ak tA ay Tee aul Pent 107 GIA CIROM ree teen Lier Gd etn eanels 107 A OT VOCTE 6 Ieee sade ana ihe Jere ean Bas 17-18 Oa ei auiuocn es ete cn 147 M Magnesium \rier Soe is ver ae 92 MAN RANE eee eenie scone waren 95 Mangels) manure gor ao) se. cee 387 Manure, adaptation .........:... 381-388 affected by digestibility of FOOD ace. A Ae ee 359-360 amount produced from food..... 351 animal food used for......... 362-363 becomes rich by fermentation .. 340 cause of difference in ........ 354-355 comes prom :tood! ute. sere eee 350
composition of drainage from... 344
concentrationofis sus ee 347 farm-yard, composition ..... 37-338 fermentation of s..-2t. oe 339
fermented in open barn-yard.... 341 fermented under shed............
SCIENCE IN FARMING.
Manure, for cereal crops ............ * 382 POTICLOVEY. so cen dec att seo 385 OSE RIBS) fies iientere Dee ee ae 384 fomsindian COrme.. 2)..0 cS eaeaeee 383 POMNIAN LOIS 2'sacis,a neki. see 387
TOM POCATOS. 25. vised <ajcem eee 388
LOM CUTNIPS: :. sree cee eee 386 from animal giving milk ........ 355 from different animals....... 348-349 from fattening animals.......... 357 from growing animals....... ... 356 improve mechanical condition of BOM Seco. eet retires gaan eee 532 leaching Of 2m cena LS eee 344 left spread over the yard........ 348 poor from poor food ............. 353 proportion of to food............. 354 relation) of food! to 2.52 25...-- 350-364 rich) from rich fodd).2. + -assee 353 rules for care’! Of. 4.425... nae 346 solid and liquid..... Lean: co Be 349 tables:.of value. 0s 2e os eaeeee 369 Valuationvob ices eee 365-373 varies with food and constitu- tion-of ‘animals yccheeecere eee 349 Manures, plant food required in. ... 330 Matter, can change its form........ 15 cannot be createds..-- eee 15 cannot be destroyed.............. 16 definition: Of | sok cu eee eee 15 forms in which it exists ......... 17 properties'of: cose siaaacneeeee 20 Milk. analysis Of. )- sete eee 280, 310 best food forts... en eeeee eee 285-294 food used in production.......... 215 key to proper food for young an- IMAals 6.5. cawewncae ease ee 280 Molecular weight...\:..0c0 0.50: ¢ssneene 77 Masculine) .22)\.4ee0es oa een eee 127 N Nature and cultivation ......:...... 319 Nitrateof s0da: - 4... +.-.-.6-08oee 108, 378 ING rates i, win shies. sae ee ROe eee 101, 108 how saved in soils 3...) 2. ae ateer 156 INTERPRE AETON cee hee oe eee 163 NGEEOPZOD:, ccc sok ee eee ee 86 amount brought down by rain.. 138 lost in ferinenting manure ...... 339 oxydized in soil’... -2.....--ee- * 329, 378
proportion stored in increase.... 357 rendered,available by bare fallow 326
*Will be found in foot note,
Numbers refer to paragraphs, not to pages.
INDEX. 185 Nitrogen not used uncombined ..... 138 R Nitrogenous substances ............. 117 | Respiration, of plants ............... 190 Nutrition, animal................ 203-208 Of ANIMAIS).2 skis napoli ean eon eee 207 re) Rock, how reduced to soil. ......... 145 MENS ATER ssa. seas ca heen gana. hion, ses 51 DHOSRUALE Ag asshole oo eran 77 QEmANTE CHEMIBETY. 20.15 sje esos vier 114 | Roots, best use in feeding ........ .. 279 matter oxydized in soil...... ... 162 improve with maturity.......... 233 substances, classes of............ 117 WiODHRODS. 2.)-.teo5 etic: aback eal 186 substances, definition .......... 71 |} Rotation, exhaustion of soils in .... 160 substances, of what composed... 114 Sach 8 POT). GIN Pater eA tata te Ral on AS 84 Sal oe SE ALR ay ep ot apn A 122 TAN ORI EM cr rs ci eye, cies Sate ae 137 RECA TN wartie AEE - 118 P Saltpeterin a. eee 108 Parasitic plants, food of............ EISt, Wa pos ne one ee Salts, containing nitrogen .......... 378 Pectose group of substances ........ 123 ane ae definition of term... .... Bese 65 Per cent, definition) of 2). .4. 00:53 24. 27 Sand 146 Pp [renee use eS RS drudge x absorbs water but slightly ...... 149 oo age BOROHSE IEE (27a egine aioe determination of character and Perspiration protects from heat .... 49 anicant 169 : Be eel, Oe ROU Eto... oye gee ie Pig, neal increase from food 299 Le retains fertilizer but little ...... 151 ape ie FRRUOS So f eum: Kies aoe 249 retains water poorly ............. 148 abraded ithe - Bee ase “"“ | Sandy soils, how improved ....... .. 175 experiments in feeding .......... 806 : - i liable to burn out ........0..24.60- 152 the farmer’s most profitable : readily. warmed .:/o): poses 152 BEOOKS oe ciee ss WARE ee te tine aes, 302.1 cg: : SCIENCES, and practices .N os sce 2 Phosnhates sie. Si isos gehe este 110 wae definition.of sais asela tee 1 preparation’ Of) wan) cash sate es 111 2 3 : in common language............. 3 rendered soluble in soil .......... 162 fuaTAtionwak 22 Phosphoric acid, insoluble .......... 367 ice iw Leda WE omar teied aie taney 25 . . . > - o5, a nats Bp ae AS proportion of in solid excrement 858 Seed, composition uniform.......... 191 BOVE LOU ani tr ic, Mies eae hts. Fed), 367 3 A contains all elements of plant BOMMIDLG tc eset arctic eae eo leree 367 foud Eipantiorus 89 OOGE DD. fching alc iees Meats Parley 91 Sere PPS eee VO RTE a fOrmation of.....\............ 191-194 Potatos, manure for. ::.....<20). 2.0: 388 als OL swat COMPOSCG.. 30. e500 182 Plants composition of ....... ... 178-181 nae a oa a ( Silieie dioxide: <i ccc, far Ae ches cote 103 exhaustion with age.....-....... 192 : E HOWAGISSGl Veds.w.n fae serae en oeeee 103 in Ded=-roOmMs y: 25664. eines ee a ss : RO i PE Es 203 STC Oe cae os hss teva Se hare EN 91 Prep 2 ie OF re Oa her Skim milk, analysis of............... 310 supplied with carbon by leaves.. 188 : Plant food t of i i] 460 valneiol for pigs 63:2 east 310 Ber abe RR ck Smoke, as a protection from frost .. 55 available, an excess needed in : : ; os, SOGICEHLORLGS i227. feet re te oer chs 106 LELTCEtT= 091 eM RMA OR Sa Toc i 3 333 i fi bydrate’..,..c/5.- A Er eet ai yates 105 available, may be exhausted .... 332 z diti ae ae 161 Soaiany 40 as es ee eee ee 92 gee ee : ies SU San tate i Soil, absorption of water from air. 149 means for rendering available 326-329 analysisof. - 157 of what composed ................ 185 ki Pdalaee OR OE a I 165 areata 367-368 baking Ofer o2.08 Ae Pp D. ti La ee tah oe tees 104 capillary attraction............. 150 ore oe nee ‘fertili Seb hel Seah orate aa chemical changes in ............ 162 P Bont ae, fe STR TE Se 104 classification Of...-.......... ... 147 an = raha Fk RN lt aaa 2 composition) of 1/05.) 2 A 144 MSE ASATLEIED 2,0 tid ik eiecsie Peeters Asa esis lees 9 condition of necessary for crop 318 *Will be found in foot note. correcting defects in............ 178
Numbers refer to paragraphs, not to pages,
186
Soilvexhaustion Of... sess ees 159 exhaustion of under rotation .. 160 fertility of affected by drainage 168
OF Minnesotans. cos oa eee 168 retention of fertilizing elements 151 retention of water by .... ...... 148 PUD GOWAN eae ne deans ee Gee 161 VEIMPCTALULE ON aise caer ee 152 Soiling, how advantageous.. .* 209, *272 SOW arg ea Sai 17-18 Soluble carbohydrates, use of term 227 definition of word................ 67 Solubility, differencein ............ 69 SSOLUULOR: 4:55 sas ae debe atthe sre eee 66 SUaGvVaAtion yeu oles ee eee 220 Straw, best in bad season ...... 192, 231 aS @milk: diets) ie: .ccee cme ter 288 Sugar, maple how produced ....... 189 SUBAUS ies fan chase acai sani eae eee 122 Superphosphates..........0.0.00..-. 379 manufacture Of... assed see 3380 T Table Salty. es sess ok ele ee eee 106 Table, air, composition of ....... .. 133 absorption of water by soils.... 149 albuminoid ratio of foods....... 263
albuminoids, composition of.... 126 digestible constituents in foods 280 comparative value of foods.... 263 comparison animal and vegeta-
ble substance ........5..65..5-. 202 composition of colostrum....... 280 composition of farm-yard ma-
IVT OS. ck ccett oie Palen axes 338 composition of food ............. 230 composition of hay at different
GSteS eka eae ee 232 composition of milk............. 280 composition of plants before
and after maturity............ 192 composition of solid and liquid
EXCIEMENE 2. cctenses seeasver O40 concentration of manures...... “347 ClENTEMtS ye he ee Sees Bol ase 83 effects of fallow ............. eeee 320
germination, temperature of... 184 manure fermented in open DaPnq-Vardiieeacor ates 841 manure fermented under ashed 342 manure left spread over a yard 343 plants ash in one ton............ 180 plants dry, waterin,............ 179
SCIENCE IN FARMING.
Table, plants, fresh, water in...... 178 proportion of nitrogen in in- crease and excrement........ 357 soils, classification of ....... ... 147 soils, compositionof............. 157
soils, exhaustion of by wheat.. 159 soils, exhaustion of under rota-
LOU cess sicibis ae oe sia eke ree eae 160 soils, retention of waterin..... 148 soils, weight of an acre ......... 155 value of manureS................ 369 value of manurial constituents
AIDA OOG ier tee sites 372 value of plant food.............. 367 value of rich and poor manure. 347 water in animal substance..... 501
Transformation of organic sub-
StANCES) aches a eee te ee 130
Tricalcic phosphate,................ 110 Tubers, storehouse of food ......... 194 Turnips, manure a bales Soe a 386 Under-feeding extravagant........ 270
Urea, formed from albuminoids... 207 Urine more valuable than solid ex-
Grement ink. 4s dee ee . 370 rapid action as fertilizer... ..... 196 Vv Valley of poison... 0. casio) sees oar 136 WiOlatieiOlis. nto. tanacaeiss ere 125 WwW
Waste of fertility by drainage ..... 156 Of The DOGY ei sso aes eee eee 206 Water ace sashes 97 amountin plants............ 178, 179 Capillary: one scsee nario 97 effect: Of in’ f00G) ova: asscc ese 276
WY ArOStatics =>. c.iacsciacosa seer 97 NYEFTOSCODICH ce anecncune eee 97 PTOI Gee eons Copa Rhea 140
“« not absorbed by plants .... 141
‘* prevents radiation ........ 53 inJanimalfsubstances............ 201
in soils requires heat toremove 50
OL COMpPINnatOn 226 ewe 97 proportion to dry food.......... 277 Weeds, best time to kill ............ 195 Weight Of SOII8 2c Paccace cern sates 155 Working animal, food for .......... 314
Young animal, proper food for. 280-284 Young grass and clover, best for
THT ie Seis ciara y stese ets eke ot ae 290
why they give good returns.... 243
Numbers refer to paragraphs, not to pages.
fi] Im the proved @x m © i @ achi snow maz of ohinery h uts it creat 18 fen as red ithin or Le SO ee mm By ape at it gone 58 Pay Beet Boresas aaa all, . sass Sos ios SHS Xe %5 Si | t £8 Sse seth , EtsRes: : 4s Xv = fy HK ie | er wae & | 4 6 Be 8B oS ie arta Xa y | igi e Ne i) ay sa ee a oN) Le eee ve My fie f | SEES wa 4 = iS it Gi le WY i | Bee He = \ he aay sith (| na s28s88 J aK mo | hk Nie MX rout i erate J wy Oo. 4 ee ap 4). a eeerte > Re Pes) SEEITiSeE un yy (pal ea esas | fa OO nn ooo F nnn noe “ = es _& EE Fos * (A ON i Faure PS He oe ! Bee cS v ay, a Lar \ oe oe Gy ap eee: O one ! ier et ear, any i ey iceia! ty, yoy oo AN H hey ty. C) XY Ni o =P BS ; ae i Lit S34 awErE ‘ ot i £5 vegans fay 1 it 45 ro} Liye ed ‘i | F is ct 238 e ne (oe ‘| 235% mee C yet om es, = rae DOO NY i ei yae! q Lae cA any BE : i > ® hee pegs WAAAY | seer leas N + i ae i cgigptee ‘ jo ns Pv, g Pas eg ofl IB Meal Ad nu ad ‘y qs O ais . } 90u9 ia aa 8 28 wees J SI 8 90u gad gece 1} we qt ae g Pe is | 08 OABy = afin ges I eae om ~S 2.2 os SS 2385 ie SPR ®
MIAMI VALLEY HERD OF
POLAND CHINA SWINE
the property of J. L. Van Doren, Glen- dale, Hamilton county, O. Stock for sale at all times. Breeders all recorded in Ohio P. C. Record. A _ correct pedigree furnished with all stock sold, All correspondents promptly answer- ed. Special rates by express. Ad- dress as above.
Roses and Flowering Plants.
Sixteen for3$1!--Your Selection.
Our descriptive catalogue, contain- ing full list of NEW and desirable va- rieties sent FREE on aephcenen.
Address, EH. BONNER & Co.,
Xenia, Ohio.
J. H DENHAM, ST. CLAIRSVILLHE, Belmont Co., O., Breeds Registered
POLAND CHINA SWINE
Merino Sheep and Jersey Cattle. His- tory of P. C. Hog 25c. Calland see me. Latch string always out.
H. S. ROSS, SEVILLE, MEDINA CO., OHIO,
Breeder and shipper Improved Ches- ter White Swine, Plymouth Rock, W.
C.B., Polands, ‘S..S:) Polish, Pekin Ducks, Toulouse Geese and Bronze Turkeys.
Stock for Sale at Ege¢es in Season:
J. L. WHITON, AMHERST, Lorain Co., O., Breeder of
— Thoroughbred —
SHORT-HORN CATTLE.
all Times:
NORTH
JERSEY RED SWINE.
I can now fill orders for single pigs or pairs or trios, not akin. Also a choice lot of Boars, old enough for service, and Sows of all ages, bred or not, as desired. I purchased my stock from Petit, of New Jersey, the cele- brated breeder of Jersey Reds, and it is all thoroughbred. nae os promitt, ly answered. SAM
Grove City, renin Comes 0.
A. M. VORE, BUCYRUS, Crawford Co., OHIO, Breeder and shipper of pure
POLAND CHINA HOGS,
Of the most fashionable strains. All Breeding stock recorded in the O. P. CG. Record. Also Plymouth Rock Chickens. Correspondence solicited.
PAUL TOMLINSON, CEDARVILLE, Greene Co., OHIO. Breeder of
SHORT-HORN CATTLE,
Poland China Pigs, Bronze Turkeys, Light Brahma, Buff Cochin and Ply- mouth Rock Fowls.
D. J. WHITMORE, CASSTOWN, MIAMI CO., OHIO, Makes a
specialty of Devon Cattle, Poland China Hogs, Cotswold Sheep, Bronze Turkeys, Tent Brahmas, Plymouth Rock and Houdan Chickens, White Guineas, Bremen and Toulouse Geese.
BERKSHIRES For Sale.
Boars fit for service. Sows
stock is not as repre- sented, will pay return charges onit. Stock regis- tered.
JOHN M. JAMISON, SoS Roxabell, Ross county, Ohio.
A. 2. & C.D. FORNEY,
Breeders and Shippers of Pure
Poland China Swine
fs" Make a specialty of this breed.
Reliable pedigrees fur- nished. PLAINFIELD, OHIO. Coshocton county,
CHICAGO SCALE CO.,
147, 149 & 151 South Jefferson street,
MANUFACTURERS OF EVERY VARIETY OF
U.S. Standard Scales.
s(aF-The Best Quality at the Lowest Prices..268
2-Ton Wagon Seales (platform Gly ers, ees $40.00 3-Ton 7x13 - += + $50.00 | 4-Ton 8x14 - = $60.00
All other sizes in proportion. All scales perfect.
Iron Levers, Steel Bearings, Brass Beam, Beam Box, and pbuilding directions with each Scale.
‘The Little Detective,” For Family or Ofiice, $3.00. Family or Farm Scale 1-2 to 24 Ibs., $5.
A $23 Farmer’s Forge for S10.
Every Farmer His Own Blacksmith. A Forge, Anvil and Kit of Tools, ? So any Farmer can do his own Jobbing, ONLY $20.
Algo, all sizes of Anvils, Wind Mills, Fanning Mills, Farm and Family Grist Mills, Hay Presses, Corn Shellers, Farm and Garden Wheelbarrows. Save Money. Get the Best. Send for List. —
JUST WHAT YOU WANT! THE RANDALL HARROW.
The most Convenient, Effective, Durable and Reliable Harrow made. Economizes time,sSaves labor and money; se- cures the largest yield of crops by the_ r®ost perfect tillage. It has no equal as a Pulver- izer, Cultivator, Sod «, Cutter, and for tilling
all tenacious and tough soils. Itis often a sub- stitute for the plow, cutting from six toten feet in breadth. Less labor and increased crops are the certain results of the use of the Randall Harrow. Half the time saved by using it to prepare the soil for seed; and it adapts itself to every condition of surface and soil. Every one who has used it or seen it used, speaks in its praise.
IT IS NO EXPERIMENT, BUT A PROVED SUCCESS !
Do Not Tramp After and Lift Your Useless Old Drag. ide the Randall, and Save Many a Weary Mile.
TESTINMONIZTALS.
From E. C, Euuis, one of the editors of the Farmers’ Advance, and a prom- inent Granger:
Last summer I saw an advertisement of the Randall Harrow, and liking the description, I opened a correspondence with the manufacturers, which re- sulted in my procuring one from them. After removing the fodder from my cornfield, I prepared the ground for wheat with the harrow alone, and I never had a crop put in more satisfactorily. Ithen got Bro. Van Doren, of Wyom- ing Grange—one of the best farmers—to try it, which he did successfully, and on returning it pronounced it the “‘Boss Harrow.” This spring he used it again with the same marked success in pulverizing the soil. I also had a ten-acre field of clover turned under, then placed the Randall Harrow on it, and I have never before seen sod put in such perfect order for corn. At the last meeting of Wyoming Grange, Bro. G. W. Raymond, our ex-Master, stated that he had a clover field that he could do nothing with. Hehad tried all the harrows in the neighborhood and none could cutit. Bro. Van Doren said to him: ‘Get Bro. Ellis’ ‘Boss Harrow;;’ it will fetch it.” He came, got the harrow, and I learn from my son that it did the work well. After so thoroughly testing it myself, and having two No. 1 farmers like our ex-Masters Van Doren and Raymond subject it to seveie tests, and getting their testimony in its favor, I feel justified in saying that the Randall Harrow will do all that the manufac- turers claim, and do most cheerfully rascommend it as the best harrow I have ever seen. E. ©. ELLIS, Glendale, Ohio.
From M. W. DuNHAM, the largest breeder and importer of Norman and Percheron horses in the United States:
Inever bought a machine I was so well satisfied to pay for as the Randall Harrow. I have thoroughly tested it on nearly all kinds of ground, corn stub- ble, sod breaking and fall plowing. No other implement can approach it for completeness of work and economy of power in surface cultivation. I am sure you will have success, for the harrow needs only to be used to commend itself as the most valuable implement in use. All purchasers will find, as I have, that you conferred a favor by placing the Randall Harrow within their reach. M. W. DUNHAM, Oak Lawn Farm, Wayne, II.
We would be pleased to mail descriptive circulars to any one applying. Agents wanted in unoccupied territory.
J. W. STODDARD & CO., Dayton, Ohio, Manufacturers.
THE BIG GIANT AND MOUND CITY a) Ne.
OUR LATEST INVENTION.
The most rapid Grinder ever made. We make the only Corn and Cob Mill w ith
proof, will give you a “mill. Ten different = styles and sizes. The only mill that sifts ==> the meal. Grinds shelled corn, makes good and grinds all kinds of small grain.
family mea
STAR CANE weenere
Grinds twice as fast. Double the capacity. CHEAPEST MILL MADE.
WARRANTED in every respect. We man- ufacture TEN DIFFERENT pees of
-and
SUGAR MAKERS’ SUPPLIES.
(OG A boy 14 Years Old Can Operate It,
Saves fuel and LABOR, makes double the quanti- y, a perfect defecator, saves 90 per cent. of labor
= = = in skimming, produces a better quality of syrup. ce This Evaporator made the syrup that was awarded the highest premium—viz. $75—at the great St. Louis Fair in 1882.
f0@ Send for circulars and prices.
J. A. FIELD & Co., St. Louis, Mo., 1622 to 1628 N. Eighth St., and 714 to 724 Howard St.
— SHOULD SUBSCRIBE FOR THE—
FARM anv FIRESIDE,
The Leading Agricultural, and Home Journal of America.
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Given Those Who Get Up Clubs.
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UPON APPLICATION. Address, :
MAST, CROWELL & KIRKPATRICK, Springfield, Ohio, and Louisville, Ky.
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OUR YOUNG PEOPLE,
A Handsomely Illustrated Paper for Young People.
ONE DOLLAR PER YEAR.
Address, MAST, CROWELL & KIRKPATRICK, Springfield, O., and Louisville, Ky.
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