OF THE SOILS OF NEW-YORK. X'35 



matter is dissipated. It is then boiled for half an hour in strong hydrochloric acid, or until 

 the soil becomes light gray 01 white. After dilution with pure water, the whole is thrown 

 upon a double filter, and washed till it is tasteless. The silex upon the niters is ignited and 

 weighed, and the niters are burnt, and their ashes weighed one against the other. The 

 filtrate is then wanned, and a few drops of nitric acid added to ensure a peroxidation of 

 the iron. Caustic ammonia throws down the alumina, the iron and the phosphates. The 

 precipitate is washed upon a double filter until the ammonia is removed, and then ignited 

 and weighed as usual. When it was deemed advisable to separate the iron and alumina, 

 caustic potash was resorted to. Frequently the whole was set down as peroxide of iron 

 and alumina. For the separation of the phosphates, pure acetic acid was employed. 

 From the remainder, the lime and magnesia were separated by oxalate of ammonia and 

 phosphate of soda. Sometimes a trial for manganese was made with hydrosulphuric acid. 

 Very few instances only occurred where even a slight trace of manganese appeared, but 

 some of the soils of the taconic rocks gave indications of its presence. Many of the analyses 

 went no farther than the process for obtaining magnesia. When a more exact determina- 

 tion of the organic matter was required, an equal quantity of the same soil was submitted 

 to the action of carbonate of ammonia, by which the soluble organic matter was separated 

 from the insoluble. 



In many instances, however, two hundred grains of soil were infused in six or eight 

 ounces of rain water for forty-eight hours, or even longer, during which time it was often 

 shaken. The whole was then filtered, and evaporated in a platina capsule. When it 

 was reduced to half an ounce by measure, it was finished in a balanced platina capsule, 

 in which it was weighed while still warm. By this method, the true amount of soluble 

 matter was determined in any given soil. The product was examined and separated into 

 its components, lime, silex, alumina, etc. : even phosphate of alumina was repeatedly ob- 

 tained from this solution. 



In conducting an analysis, we have been sensible that great care was necessarv, and 

 that each should be carried to an exact determination of all the components, especially the 

 alkalies, the phosphates, and the saline matters which are known to be essential to vege- 

 tables. Many persons express a doubt whether the analysis of soils is of any service at 

 all, but we regard such an expression as altogether too sweeping in its declaration. The 

 determination of the existence of lime and magnesia in a soil is certainly important. It is 

 true, that so far as silica and alumina are concerned, analysis is of but little use ; but every 

 other determination is of some utility. There are, moreover, other reasons for pursuing 

 analytical investigations of the soils of this State. No one has ever taken up the subject 

 with reference to the soils of sedimentary rocks, the limestones, slates and shales. Presi- 

 dent Hitchcock has analyzed many of the soils of Massachusetts, and Dr. Jackson those of 

 Rhode Island and New-Hampshire ; but these are principally soils of primitive formations : 

 they could not throw much light on those of this State ; and hence we could not but feel 

 that the work of analysis would be attended with useful results, though in many instances 



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