124 Report of Farmers' Institutes 



2. Method of Manufacture. There are at least three different 

 processes of making lime nitrate, but all are based on the same 

 general principle, differing only in some of the mechanical de- 

 tails. Briefly stated, the general process consists of the following 

 operations: (1) Ordinary air is passed through a powerful elec- 

 tric arc or flame, resulting in the combination of more or less 

 of the oxygen and nitrogen in the form of nitric oxide. (2) This 

 nitric oxide, on exposure to air, combines with more oxygen to 

 form nitrogen dioxide. (3) By treatment with water this last 

 oxide is converted into dilute nitric acid. (4) The last step is to 

 concentrate the nitric acid and treat it with calcium oxide and 

 carbonate, fonning calcium nitrate. 



There have been reports of the organization of factories in this 

 country, one in South Carolina and one in California, but little 

 definite infonnation is yet available. 



3. Cost. Nitrogen in lime nitrate is estimated to cost about 

 15 cents a pound at the factory. 



4. Availability. Calcium nitrate is easily soluble in water and 

 its nitrogen is taken directly into plants. 



5. Effects of use of calcium nitrate. Calcium nitrate leaves in 

 the soil, after the nitrate has been absorbed by plant-roots, cal- 

 cium, which becomes carbonate under normal conditions, and on 

 this account is a more desirable compound to use than sodium 

 nitrate, which leaves sodium carbonate — a compound which in 

 sufficient quantities may destroy the granular structure of the 

 soil. 



It is of interest at this time to know that the development of 

 this method of making nitric acid has made it possible for 

 Gei-many and Austria to be wholly independent of all outside 

 supplies of nitric acid, which is an absolute essential in the 

 manufacture of all high explosives as well as gunpowder. 



NITROGEN COMPOUNDS PREPARED IN THE WET WAY 



Within a few years fertilizer manufactureirs have found a 

 method of making legitimate use of various waste materials, rich 

 in nitrogen, which in their original form contain practically no 

 available plant-food. Chief among such wastes and refuse are 

 hair, garbage, tankage, leather, scraps, etc. 



