78 BOARD OP AGRICULTURE. [Jan., 



In 1820 the first cargo was sent to England, but was tlirown 

 overboard in harbor because the duty was so high that it would 

 not pay to pass it through the custom house. In 1830 a cargo 

 came to the United States, but there was no sale. In that year 

 18,700 tons were exported from Iquique ; in 1840, 227,300 tons; 

 in 1850, 511,800 tons: in 18G0, 1,370,200 tons; in 1870,2,743,400 

 tons. In 1872 the amount had risen to 4,000,000 tons, and in 

 the following year the Peruvian government took the matter into 

 its own bands and decided to export only 4^ million tons annually, 

 so as to keep the price constant. 



At present the region is in the hands of the Chilian govern- 

 ment, and is likely to remain there. 



Till now only one grade of nitrate of soda has appeared in our 

 market, and that has never shown any fluctuation in composition, 

 running from 94 to 96 per cent, of pure nitrate of soda with from 

 I to H per cent, of salt, 2^ per cent, of water, and a very little in- 

 soluble matter. 



In Germany a manufacturing bye-product called potash-soda 

 saltpeter has been introduced and found favor with farmers. It 

 has 34 per cent, of potash-saltpeter and 6 1 percent, of soda-saltpeter, 

 equivalent to a little less nitrogen than the pure soda-saltpeter, but 

 contains 15.9 per cent, of potash, which replaces an equivalent 

 amount of soda. It has not yet appeared this side the water. 



Owing to the high prices of amraoniacal matters which have 

 prevailed the last season, it is probable that saltpeter will be very 

 considerably used by manufacturers in the goods sold this winter 

 and the coming spring. It is important in using manures contain- 

 ing nitrates that they should be applied immediately before the 

 crop is put in. Nitrogen from a nitrate may waste more by di-ain- 

 ing in a few weeks than from fish or blood in all the winter 

 months. 



Another source of nitrogen is the ammonia salts, particularly the 

 sulphate of ammonia, which is now chiefly obtained as a bye-pro- 

 duct in the gas manufacture. "When of fair quality it should con- 

 tain from 16.5 to 20 per cent, of nitrogen, or from 77.7 to 94 per 

 cent, of the pure salt. 



I understand that lately there has come from England and been 

 offered in our market a crude sulphate of ammonia, said to con- 

 tain ^^ to 8^ per cent, of nitrogen. Its general look does not cre- 

 ate a favorable impression, and low-grade ammonia salts are quite 

 apt to contain sulpho-cyanide of ammonia, a substance rich in ni- 



