72 Farmyard Manure. 



In a similar manner the proportions of organic and inorganic matters in the 

 insoluble portion of the manure was ascertained. 



The nitrogen was determined in each portion separately by combustion with 

 soda-lime, and collecting the ammonia produced in sulphuric acid of known 

 strength, according to Peligot's method of determining nitrogen in organic 

 matters. 



Frequently two combustions were made with one and the same substance, 

 and invariably closely-agreeing results obtained. 



The ash-analyses of the soluble and the insoluble mineral matters of 

 manure, were executed according to the method described in Professor Wb'hler's 

 ' Handbook of Inorganic Analysis,' under the head '* Analyses of the Ashes 

 of Plants." 



The amount of free ammonia in the manure was ascertained by placing 

 into a wide-mouthed retort from 500 to 1000 grains of manure, adding about 

 8 ounces of water, and distilling off about 4 ounces into a glass bottle, con- 

 nected air-tight with the retort on the one hand, and on the other with the bulb 

 apparatus usually employed in nitrogen combustions. Both the bottle and 

 the bulb apparatus contained some hydro-chloric acid. The contents of both 

 were evaporated to dryness on the water-bath, and from the dried residue the 

 amount of free ammonia calculated. 



To the manure in the retort, from which the free ammonia was distilled off, 

 quicklime and a little more water was added, and the whole distilled nearly to 

 dryness into hydro-chloric acid as before. 



Distilled water was next poured upon the mixture of quicklime and manure 

 in the retort, and after some time the liquid filtered through filtering paper. 

 The insoluble portion was washed several times, and the washings added to 

 the first filtrate, and the whole clear solution evaporated to a very small bulk. 



This condensed liquid, which in most cases was coloured merely light yellow, 

 finally was tested for nitric acid with the usual tests. 



LONDON : PRINTED BY W. CLOWES AND SONS, STAMFOKD STREET, 

 AND CHARINO CROSS. 



