A BARN-FLOOR LECTURE. BY DR. J. R. NICHOLS, OF MASSACHUSETTS. [Though the accompanying lecture is not new, it is of value, and is published with permission of the author, by the request of farmers who are unable to obtain copies.-SECRETARY.] GENTLEMEN :—I have invited you here to-day in fulfilment of a desire long entertained, of bringing around me for a couple of hours, on my farm premises, a body of practical men-workers in the field—that I might illustrate and explain to them methods of procuring, manufacturing, and combining those important elements of plant food which modern science has brought to view within the past quarter of a century. We meet under peculiar circumstances and in a peculiar place, but in one most appropriate. We are under the same roof that shelters the products of these fields and the animals we so highly prize, and here around us are the implements of husbandry; and it is here that for a period of sixteen years I have studied and experimented upon improved methods of farm management, and the fertilization of crops. It is here that as long ago as 1863 were commenced systematic experiments with what are known as chemical fertilizers, and probably there is no farm in the country which has been so long an experimental one as this to which you have been called to-day. During the time it has been in my possession, Lakeside farm has more than trebled its productiveness; and when I tell you that not a load of animal excrement has been purchased, and that the only animals maintained the first five years were a couple of cows and two horses, and that during the past five years but six animals, all told, have been kept to supply excrement, you will understand that I must have maintained fertility through some other sources than the manure heap. During the intervening period between 1868 and 1872, a herd of seventeen animals, mostly cows, was kept at the farm, and the use of chemical fertilizers was suspended except upon experimental fields. The productiveness of the farm diminished during that period, and my anticipations were verified by the results. The farm is now mainly devoted to raising hay, as the soil is well adapted for the growth of grass. Our crop the present season is probably not far from fifty tons. The present is the first season that a corn crop has not been raised. There is a field upon the hill yonder from which have been taken two fine corn crops and one of rye in the past three years, using only our farm-made chemical fertilizers. The land was rough pasture, covered with stones and briers, before it was put under the plough. The field opposite this barn is an experimental field, or rather was for a period of ten years. From that field have been gathered three crops of corn, two of rye, one of wheat, and four of hay, in ten consecutive years, and the dressings have been solely chemical food, such as the crops required. At the expiration of ten years it received a thorough dressing of barnyard manure, eight cords to the acre. A diminution of crops followed, and it is not now in satisfactory tilth. A good illustration of the value of chemical fertilizers, properly adjusted and compounded for grass, may be seen in the richness and luxuriance of the lawns connected with the stone mansion in view on Winnekeni hill. These lawns are four acres in extent, and no part has ever received any barnyard or stable dung. The soil was common pasture, and never probably received any manure other than the droppings of the animals feeding upon its grasses. At the close of the meeting I trust you will find time to examine the grounds. But, gentlemen, this is not properly a field meeting, it is a farmer's barn meeting, or, for the time being, we will call it our agricultural college, and I promise to graduate you all in about an hour, without diplomas. You are to learn how to prepare, combine, and use the new fertilizers about which so much talk is made in these modern times. I have always taken the ground that farmers can and should prepare their own fertilizers on their own premises. This has been advocated in addresses before our State Board of Agriculture, and in all my writings upon husbandry, and now it is designed to show you here how it is or can be done. Probably never before in the history of agriculture in our country has a meeting like this of farmers been held in such a place for such an object. It is new, it is an experiment, but there can be no doubt of its entire success. I have great confidence in the eye-I believe in seeing: sight is the readiest avenue to the mind. At the close of the lecture, Mr. Davis, the efficient superintendent of this farm, will call you into the barnyard contiguous, and then, with apparatus and implements such as are used on the farm, will proceed to prepare, not simply an ounce or a pound, but five hundred pounds of superphosphate of lime, the most important of all forms of plant food. He will also show you other combinations of fertilizers, a knowledge of which it is important to possess. You have seen the room or laboratory below, simple, plain, and without machinery, in which the fertilizers for the farm are prepared. In that room, Mr. Davis, during the past winter, made about twelve tons of superphosphate of high grade, analyzing sixteen per cent. of soluble phosphoric acid, and also several tons of other compounds used in the various crops on the farm. He will use three hundred and eighty pounds of bone charcoal, and a carboy of oil of vitriol of one hundred and sixty-five pounds, in making the superphosphate; and you must observe all the proceedings, observe how he handles the carboy so as to avoid spilling or slopping, how he mixes the bone with the acid and water, how he manipulates the mass with his wooden hoe. The box in which he will make the mixture is of wood, four feet square and one foot deep, and it is lined with thick sheet lead, the lead in one piece, soldered at the corners strongly with lead solder. A tin solder will not do, as the acid will act upon it. This box is the result of much experiment, and is the best and cheapest vessel that can be devised. Its capacity is just right for making one fourth of a ton of superphosphate at a time, and it requires a whole carboy of vitriol, so that no fractional parts of acid are left to cause trouble. He will use in the manufacture, 1 carboy oil of vitriol, Water, 165 pounds. 380 pounds. 10 gallons. The water is first placed in the trough, and the acid is added to it; then the bone is gradually added causing a great boiling, with evolution of heat and steam, as you will see. You observed in the laboratory that there were roof windows that could be opened for letting out the steam: these are necessary. It takes about an hour for the reaction to become complete, and then it will soon dry and be free from moisture. It needs no grinding; it is ready for the field as soon as cool. Specimens of each lot as made here are taken to the analytical laboratory, and analyzed You have vis to ascertain how perfect has been the reaction. ited the laboratory, up stairs, at the end of the building. This is necessary for the chemist, as it is there all his results are worked out, but it is not needed by you. You will need a cheap room with good ventilation for the manufacture, and the simple implements you see here are all that are necessary. In order that you may understand the nature of the materials and compounds we prepare, I will now proceed to state the chemical constitution of bones, and what changes bone structures undergo when subjected to chemical treatment. The bony framework of men and animals is essentially alike, and the molecules of which they are composed come from the foods consumed. The bones which hold up the muscles and integuments of our animals come from hay, grain, green forage, &c. It is necessary for cows to procure a much larger amount of bone material than they need for the repair of osseous waste in their bodies, for the composition of milk calls for a large amount of the phosphates. When you learn that in about every thirty gallons of milk there is one pound of tribasic phosphate of lime, or bone material, you will have some idea of the importance of this substance in the food of cows. The bones of the infant, fed on milk, come from this principle; and hence we learn the medium through which human or animal structures are built up. Permit me to remark in passing, that it must be obvious to you that an animal in milk, like a cow, cannot yield excrement of high value. Most of the rich material obtained from the pasture, or from any form of food, goes to the milk, and hence little is left of value to return to the soil. We often hear farmers say they keep cows and sell milk so as to maintain the fertility of the farm. This is absurd, on the principle that you cannot eat your pudding and have it too. A cow in milk requires about eighty pounds of bone material a year, and consequently a herd of twenty-five cows will carry off from our pastures and the barn a ton of bone materials each year. It is apparent that this process of exhaustion cannot continue for a very long period without rendering our fields sterile. We must return to them the bone material they have lost: we must, in other words, feed our hungry plants upon the soluble phosphate of lime, and thus give to them renewed vigor; and they in turn will yield the same back to our animals, and from them our own bodies will be nourished. Plants cannot assimilate bone in its ordinary condition; it must be rendered soluble in water before it can enter plant structure. How this is accomplished it is important to understand. Phosphoric acid, the element in bone which plants require, and which therefore becomes what we call a fertilizer, is not the only kind needed to render our fields productive. It is one of the three great essentials of plant food, for there are but three that we need trouble ourselves particularly about. The others are nitrogen and potash. It is proper to remark here that the great bulk of all vegetable structures comes from the air, and is therefore furnished abundantly and gratuitously. What concerns us directly is the matter of furnishing proper supplies of phosphoric acid, nitrogen, and potash to our fields and crops, and it is our business to learn how to obtain, prepare, and apply these substances. Now, first let us consider phosphoric acid, what it is, and how we are to fit it for plant nutrition. I shall use in the experiments this afternoon what is known as bone charcoal, for the purpose of developing or setting free phosphoric acid, and here it is in the vessel before you. It is, as you see, a black, granular substance, resembling coarse black sand. This substance is simply burned bones, bones charred or changed into animal charcoal by heat. The animal portion, or the gluten, is carbonized, and the bone structure destroyed. It is a substance largely employed by sugar refiners to decolorize syrups, and after it |