MUSCLES. 279 



when kept, it exhales an urinous odour, especially when ammo- 

 nia is added to it When heated in an open dish it gives out a 

 very strong urinous smell ; it is then charred, and gives out a 

 smell exactly similar to that of burnt tartar, and finally swells 

 up, as happens to a vegetable acid united to an alkaline base. It 

 dissolves in water, and the solution has a yellow colour. Infu- 

 sion of nutgalls and corrosive sublimate throw down a very scan- 

 ty precipitate ; and this is the case also with acetate of lead and 

 nitrate of silver. Diacetate of lead throws down a very copious 

 precipitate ; oxalic acid throws down oxalate of lime ; lime- water 

 throws down nothing. But if we mix the extract with a good 

 deal of hydrate of lime, and boil for a long time, a disagreeable 

 ammoniacal smell is disengaged, the hydrate becomes yellow, and 

 a great proportion of the extract is decomposed. If it be now 

 treated with animal charcoal, little remains but lactic acid and 

 salts, which may then be separated. Nitric acid occasions the 

 formation of no nitrate of urea, but after some weeks crystals of 

 saltpetre make their appearance, from the decomposition of lac- 

 tate of potash. 



The extractive matter soluble in absolute alcohol contains at 

 least two substances, which were separated from each other by 

 Berzelius in the following manner : 



(1.) Corrosive sublimate threw down a yellow precipitate, 

 which was mixed with water, and a current of sulphuretted hy- 

 drogen passed through the mixture. A yellow solution remain- 

 ed, which had an acid reaction. When saturated with carbonate 

 of lead and evaporated, it left a deep yellow matter, from which 

 neither absolute alcohol nor alcohol of 0*833 is capable of dis- 

 solving the extractive which remains combined with the chloride 

 of lead. But it readily dissolves in water, and the solution is 

 precipitated by corrosive sublimate, but not by acetate of lead or 

 protochloride of tin, and very little by diacetate of lead. Ni- 

 trate of silver throws down the extractive matter combined with 

 chloride of silver. This portion of extractive matter possesses 

 the following properties : its colour while in solution is light- 

 yellow ; it has no taste, and has a great tendency to combine 

 with salts, on the nature of which depends its solubility or inso- 

 lubility in alcohol. Its compound with corrosive sublimate is 

 orange. It is slightly soluble in water, but not in water con- 

 taining an excess of corrosive sublimate. It is this substance^ 



