ANALYSES OF THE POTATO. 37 



from either half. The acetic solution, however, must be first neutralized by carbonate 

 of ammonia, when the albumen goes down, and from which the liquid must be freed. 

 It may then be evaporated to a small bulk, and alcohol added in a large quantity, when 

 the dextrine appears in flocculi which must be left to subside. It may then be filtered 

 upon a prepared filter, and weighed. The remaining liquid is now evaporated in water, 

 in a cup whose weight is accurately determined, until it ceases to lose weight : this matter 

 is called sugar. The fibre which had been obtained in an uniform state, is freed from 

 fatty matter and gluten by means of alcohol in a retort. Ether is afterwards employed 

 to free the gluten from fat, which is cautiously distilled off or evaporated in a weighed cup. 



My readers will now be prepared to set a proper value upon the labors which have been 

 performed in the laboratory. The foregoing statements, I hope, have also prepared the way 

 for entering upon a detailed account of the results which have been obtained. I shall, in 

 the first place, give the analyses of the potato plant ; and I may again say that the order 

 of arrangements is governed by necessity, being obliged to give in the first place the 

 analyses of those substances which are in the greatest state of forwardness ; and as analyses 

 are still in progress, and will be for three months to come, those which are made hereafter 

 will be placed in an appendix. 



The analysis of the potato plant is extended to the stalks, leaves and tubers ; they have 

 not been confined to the tuber. All the varieties which I could obtain have been analyzed. 



I. MERCER POTATO. 



Color white or grayish white ; flesh white ; form elongated, much longer than wide. 



The potatoes analyzed were raised in Cortland county, by N. Salisbury, Esq. Length, 

 5 inches ; thickness, 2\ inches. 



1. Analysis of the ash of the whole "potato. 



Silica * 4-400 



Phosphates • * » - * - - 38-500 



Lime * * 0-150 



Magnesia 0-800 



Potash - 13-263 



Soda - - ... . . - - 24-925 



Sulphuric acid -•■--.-. • . 6-254 



Carbonic acid ..... ^ trace. 



Organic matter ....»».. 2-536 



102-434 S. 



