and we get first the metallic phosphorus, which you see here, which must be burned to get the phosphoric acid, in contra-distinction to the usual method for the manufacture of phosphates, which is by a treatment of the rock with sulphuric acid.

After the phosphoric acid is obtained, it is easily possible to add the nitrogen, in the form of ammonia, and potash, to it and get such materials as the potassium and ammonium phosphate such as I show you here.

Another line of work which has been very productive of results is the ammoniation of organic substances. We have found that by taking such substances as peat, of which there is a very large acreage in the United States, and treating it with anhydrous ammonia under heat and pressure, we can actually get as much as 21 percent nitrogen in the peat. We find that when this is used for fertilizer purposes the nitrogen is available, and furthermore the peat breaks down and acts like other organic matter in that case. Normal peat does not decompose readily in the soil, but after it is ammoniated it does decompose, and you get a very fine nitrogen carrier in the ammoniated peat. That [indicating] is some that has been ammoniated to the extent of about 10 percent.

We find that other organic substances will also act in the same way. Here [indicating] is a sample of leather and a sample of tankage that has been ammoniated. You will notice the large amount of nitrogen. that has been injected into this material, running about 12 percent in the case of the leather, and I think around 10 or 12 percent in the case of the tankage.

We have done considerable work in the placement of fertilizer. We find that fertilizers can be made much more efficient and the amount of fertilizer necessary for a crop may be reduced considerably, at least 10 percent, by the proper placement of the fertilizer. With certain crops like cotton we find that by placing the fertilizer to one side, and about at the depth of the seed, we get a much higher efficiency than if it is placed on the surface or directly below the seed.

Now, if you would like to have further details in regard to this work, I will be glad to have Dr. Kunsman go over these projects.

Mr. SANDLIN. All right, Dr. Kunsman; we will be glad to have you take up these projects and tell us what is being done."

Dr. KUNSMAN. Mr. Chairman, with your indulgence I shall proceed to outline briefly the work of the fertilizer investigations unit as carried out under its seven major projects or lines of work.

CATALYSTS IN NITROGEN FERTILIZER INVESTIGATIONS

Our catalytic laboratory was the first and is still the only catalytic laboratory in the United States for agriculture and industry. In this laboratory was developed a nitrogen fixation catalyst equal to any existing throughout the world. This catalyst, together with tests on the properties of gases at temperatures and pressures at which they are carried on industrially (work now carried on in the physics and chemical fertilizer investigations project), as well as with certain mechanical and engineering development, formed the basis of a nitrogen fixation industry in this country now adequate for both peaceand war-time demands. Important developments have taken place in obtaining cheaper and purer hydrogen from water gas, which is a mixture derived from treating coke with steam. A cobalt catalyst

is the basis of this process, while an iron aluminum oxide mixture forms the basis of the catalyst used to convert a mixture of nitrogen and hydrogen into ammonia. Within the last year a catalytic problem has originated in connection with the oxidation of phosphorus to P20, or phosphoric acid. This has direct application to our high temperature or blast-furnace project for the production of phosphoric

acid.

TRANSFORMATION OF NITROGEN COMPOUNDS

With 4-cent to 5-cent ammonia (wholesale price paid for ammonia by fertilizer manufacturers this last year) the utilization of this fixed nitrogen in fertilizer salts is of great importance. Urea is such a salt. It is a high nitrogen carrier and a very desirable compound in the soil because it leaves no undesirable residues on being assimilated by the plant. Some of the first and basic work on urea synthesis was carried out under this project, which proved so promising that it was further prosecuted by industry with the result that during the past year a considerable tonnage of urea ammonia mixture has gone into the fertilizer industry. This was accomplished through the use of the mixture in the ammoniation of superphosphates. You will see from the exhibit that the product has excellent physical properties and is a desirable fertilizer ingredient. This accomplishment resulted in the reduction of the amount of urea and calurea imported during the last year to about half. Another project of considerable importance is the ammoniation of peat. From the samples that Dr. Knight has just shown to you, you will see that an abundant and widely distributed deposit such as peat can be transformed into a nitrogen carrier containing up to 21 percent by weight of nitrogen. We believe that this material, which has excellent physical properties, may become an important factor in the fertilizer trade. The material is now being manufactured on a laboratory scale and distributed to experiment stations in small quantities for vegetative tests. This synthetic product should furnish a substitute for the more expensive organics, such as cottonseed meal, fish scrap, etc., now extensively used as cattle food. The average wholesale price of these has been about 10 cents a pound this last year as compared with the average price of nitrogen in fertilizer salts of from 5 to 6 cents a pound.

Ammoniated peat may also be one of the substitutes for the acidforming fertilizer materials now more extensively used due to the lower cost and increased use of ammonium sulfate.

BIOCHEMICAL AND ORGANIC NITROGEN FERTILIZER INVESTIGATIONS

You are no doubt familiar with the fact that growing plants fix a great deal of their own nitrogen from the air. To give you an idea of the importance of this, it has been estimated that about 90 percent of the nitrogen used in plant growth has its origin in bacterial fixation, the remaining 10 percent coming from commercial fertilizers. One of the objects of this project is to discover nature's method of fixation. with a view to using these facts in increasing the efficiency of our present application of commercial fertilizer. In this connection, the importance of calcium, strontium, iron and soil humus in bacterial fixation was demonstrated. The isolation of a nitrogen fixation enzyme was an important discovery during the past year. This enzyme has properties in the bacterial fixation process similar to the

vitamin characteristics in the human diet. In the organic investigations interesting results connected with the organic constituents of ammoniated peat and other proposed synthetic organic nitrogen carriers have been obtained. This work is also directed toward a synthetic organic compound to replace the more expensive organics now being used in fertilizers.

PHYSICS AND CHEMICAL FERTILIZER INVESTIGATIONS

In the physics and chemical fertilizer investigations we aim to determine the fundamental steps involved in how nitrogen, phosphorus and potassium compounds combine into fertilizer salts. The X-ray, spectroscopic, high-temperature, and high-pressure laboratories all play a very important role.

These laboratories are available and are becoming more important in connection with other projects in our own as well as other bureaus of the Department of Agriculture. This last year considerable cooperative X-ray spectroscopic and photochemical work has been carried on with the Bureau of Plant Industry, with minor services rendered to a number of other bureaus. Some of the most up-todate methods and equipment have been developed during the last few years and are now being more broadly applied throughout the Department. The X-ray analysis method of classifying soils has been determined; also the crystal structure of phosphate rock showing fluorine as an integral part of the molecule. A knowledge of this structure has shown why many attempts to free fluorine from phosphate rock were not successful, with a savings in effort and funds. X-ray analyses of fertilizer salts have been used where other methods failed to clarify certain properties of these mixtures, as hygroscopicity and caking on storage. Types of compounds present in superphosphates, and the state of hydration of calcium phosphate in relation to the hygroscopic properties of superphosphate in mixtures is now being actively investigated. The spectroscopic method is the only method of studying chemically active states in comparison with the inert states of nitrogen. Properties of the various nitrogen oxides were determined. The spectroscopic determination of impurities in plant residues and traces of metals in bacterial fixation are being investigated. An experimental and mathematical analysis of the physical properties of nitrogen, hydrogen, carbon dioxide, methane, and other mixtures, over a wide range of temperatures and pressures, under conditions in which these gases are used industrially, is being continued. This is the only Government laboratory, as well as the only laboratory in the country, where much of this information can be obtained.

PHOSPHATE FERTILIZER INVESTIGATIONS

Our phosphate fertilizer investigations have comprised a survey of the occurrence, production, reserves and chemical composition of phosphate rock existing in the United States, which was completed during the year. A method of extracting fluorine from phosphate rock at 1400° C. in the presence of steam and silica was perfected. The relatively low plant food value or nonavailability of natural phosphate rock is attributed to the fluorine content. This process has very important industrial possibilities and when applied commercially should produce a phosphatic material at prices comparable with or

lower than the cost of producing superphosphate by the sulphuric acid, or batch process. Indications are that approximately 75 percent of the fluorine in the phosphate rock can be recovered by this new process as compared with 20 percent recovery in the present method of manufacturing superphosphates. The fluorine compounds are becoming of increasing importance as insecticides and agricultural poisons. The superphosphate produced by this method should ultimately be a partial substitute for bone meal, a mineral supplement for livestock feeding, with a proportional saving to the domestic livestock industry. Here we have a sample of the calcined phosphate prepared by heating phosphate rock at 1400° C. in the presence of steam. This mixture contains about 30 percent available phosphoric acid for plant food. Considerable work was also carried on on the properties of ordinary superphosphate and double superphosphate. The exhibits of superphosphate and double superphosphate, together with the ammoniated product, are furnished for your inspection. You will see from the analyses of the samples that ammoniated superphosphate contains about 18 percent P2O, and 2 percent to 3 percent of ammonia, while the double superphosphate contains 43 percent to 45 percent of P2O, and 6 percent to 10 percent of ammonia.

When it is demonstrated commercially that the ammoniated double superphosphate can be manufactured as cheaply as the ammoniated superphosphate you will have a fertilizer with approximately twice the plant food content with the same excellent physical properties. This is a development which should result in a proportional saving to the farmer in freight and handling.

In our blast furnace project for the production of phosphoric acid, a 500° F. increase in temperature was obtained which resulted in the consumption of less coke and therefore cheaper phosphoric acid. Advances have also been made in collecting the elementary phosphorus.

POTASH INVESTIGATIONS

Within the past year appreciable advances have been made in freeing the country from the domination of foreign potash producers. This country produced 50 to 60 percent of the actual requirements of potash this past year, which is about 30 percent of the normal requirements for the country. About $9,000,000 was paid to Europe for potash in 1932. For the last few years particular attention has been devoted to that phase of the potash problem designed to provide cheaper potash for the Middle West and Northwest, from the abundant vocanic lavas of Wyoming. These deposits, fortunately, are situated closely contiguous to the world's greatest known phosphate deposits located in Wyoming, Utah, Idaho, and Montana, and to cheap coal and other raw materials. The development of a fertilizer industry for this section of the country will ultimately be of the first order of importance as the cost of fertilizer salts and materials is largely affected by transportation rates. Our blast furnace project plays an important role in this development. The project contemplates a complete fertilizer with the lowest possible production cost and of the maximum. plant food concentration with the lowest distribution charge. The results of these researches are also applicable to other sections of the country, for example, Muscle Shoals. Extensive investigations have also been carried on with a view to producing potassium sulphate. This for years has been the preferred form of agricultural potash,

demanding a higher market price, and is an essential in the manufacture of chlorine-free fertilizers. For the past 10 years the United States has imported from Europe on the average of 3 million dollars worth of potassium sulphate annually. The possibility of obtaining potassium sulphate from our natural polyhalite deposits in New Mexico has also been investigated and is showing promise.

CONCENTRATED FERTILIZER INVESTIGATIONS

The concentrated fertilizer investigations are carried on from the point of view of developing new and improved fertilizer mixtures; a study of the chemical reactions in fertilizer mixtures; investigation of methods for increasing the efficiency of fertilizers by improving their physical and chemical properties; development of formulas of concentrated fertilizer mixtures with satisfactory physiological quality; compilation of fertilizer statistics, and the development of new and improved methods for the preparation of concentrated fertilizer materials. You will notice from the tables and charts now before you that since 1900 considerable changes have taken place in materials used in the manufacture of mixed fertilizers. The most striking trend has been the increased use of ammonia nitrogen and the decrease of nitrate nitrogen or sodium nitrate. The average mixed fertilizer sold in the United States in 1913 contained 2.2 percent nitrogen, 8.9 percent P2O, and 3.9 percent K2O, or a total of about 15 percent plant food; in 1931 the concentration of mixed fertilizers had increased so that the average analysis formula was nitrogen 3.3 percent, P2O, 9.5 percent, K2O 5.1 percent, making a total of 17.9 percent of plant food. If no filler had been used in making these mixtures they would have contained an average of 16.6 percent of plant food in 1913, and 21.1 percent in 1931. Very little filler is used at present in New England and the central and western States, but in the South where most fertilizer is consumed relatively large quantities of filler are used.

It is estimated that one State alone pays about $1,000,000 a year for filler. As seen from the data and curves the trend is towards fertilizers with increased plant food content. However, this may not be taking place as rapidly as the advances in fertilizer technology would indicate. An estimate of the savings in the South, brought about by the elimination of 20 percent of the unnecessary filler (by filler I mean those materials which are added that have no plant food value) would be from $1 to $1.25 per ton. This would result in an average saving on the farmer's fertilizer bill for the entire country of about $1 per ton. Since in 1932 about 4,362,000 tons of fertilizer were consumed in the United States, and a saving of that many dollars would result. When double superphosphate can be substituted for superphosphate at the same price an additional saving up to $2.75 per ton on fertilizers should be realized. Another development of utmost importance is the substitution in fertilizer mixtures of fertilizer salts which are slowly available as a plant food in contrast to those fertilizer salts which are immediately water soluble and immediately available. By the proper mixture of salts, those that are immediately available and those that are slowly available, the necessary plant food can be supplied to the germinating seed and growing plant. Magnesium ammonium phosphate is one of those materials now presented for your inspection.