HALF PLASTER. 



339 



per cent — of both fertilizers consisted of gypsum : the re- 

 maining portion was, apparently, in the main, ashes, salt, and 

 some acid sulphate of soda. Their conposition proved so 

 much alike, that it is quite safe to assume, that no serious 

 changes in results will be produced in case the carrot-fertilizer 

 should be used for the production of corn, and the corn-fer- 

 tilizer for that of carrots. 



Improved Poudrette. 



The material which served for the following analysis was 

 furnished by a gentleman in the eastern part of the State for 

 the purpose of ascertaining the amount of its essential con- 

 stituents as compared with that of other fertilizers, to 

 secure a basis for an approximate valuation of their respec- 

 tive merits from a merely commercial stand-point. 



Per cent. 

 Organic and volatile matter 65.60 



Ash-constituents 34.42 



Moisture at 100° C 34.58 



Nitrogen, partly in form of ammonia . . . 2.00 



Total phosphoric acid in ash .... 2.07 



Soluble " « « 1.98 



Insoluble " « « .09 



Potassium oxide .18 



Calcium oxide (lime) 7.46 



Sulphuric acid 13.03 



Matter insoluble in diluted acids .... 16.62 



Chlorides, &c Not det. 



The article, which, according to information received, 

 came from an establishment near Newark, N.J., was sold at 

 a depot in New- York City at sixteen dollars per ton of two 

 thousand pounds. The price charged for the poudrette fer- 

 tilizer compares quite satisfactorily with the present market- 

 prices of its essential constituents as specified in the above 

 analytical statement. Its application had produced satisfac- 

 tory results in the estimation of its purchaser. One of the 

 noticeable features of this fertilizer consists in its large per- 

 centages of gypsum, and of earthy, insoluble matter, — from 

 three hundred to four hundred pounds of each per ton. 

 Both substances are apparently added to serve as absorbers 

 of moisture ai\d ammonia, for which the calcined gypsum in 

 particular is well adapted. Taking every thing mto consid- 



