LITHOFELLIC ACtD. 23 



posed gall-stone in the zoological cabinet of that place, labelled, 

 a gall-stone consisting of concentric layers. There was no ac- 

 count of its origin or history. It was oval, had a nucleus of al- 

 bumen coloured by bile, weighed 240 grains, and had a specific 

 gravity of 1*043 at the temperature of 68. It was insoluble in 

 water, muriatic acid, and acetic acid ; slightly soluble in ether, 

 and readily soluble in boiling alcohol, with the exception of a 

 little albumen coloured greenish-brown by bile. From this so- 

 lution it crystallized in hard pulverizable crystals, which Wohler 

 found to be short six-sided prisms. 



When heated in a platinum spoon it melted into a yellow li- 

 quid, which caught fire when the heat was raised, leaving a small 

 quantity of shining charcoal, which gradually burnt away without 

 leaving any residue. 



When heated with nitric acid it frothed strongly and the acid 

 was partly decomposed, then it dissolved in the surplus acid. 

 The solution being evaporated left a beautiful lemon-yellow mass 

 insoluble in water ; but when rubbed or heated in that liquid it 

 assumed the appearance of a white resin. 



When heated with potash ley it is saponified, giving out the 

 smell of ambergris. From this soap acids throw down a yellow- 

 ish white powder, identical with the crystals from the alcoholic 

 solutions, and constituting a new acid, to which Goebel has given 

 the name of lithofellic acid. 



To obtain this acid the concretion was dissolved in boiling al- 

 cohol of 99 per cent, and the greenish brown filtered liquid slow- 

 ly evaporated. The acid was deposited in crystals coloured 

 greenish yellow by bile. They were pulverized and washed with 

 cold alcohol to remove the colouring matter, and again dissolved 

 in boiling alcohol and crystallized. They were now nearly co- 

 lourless. The crystals were oblique prisms with oblique termi- 

 nations. 



At 68 it dissolves in 29*4 times its weight of alcohol, and in 

 six and a-half times its bulk of boiling alcohol ; 44*4 parts of 

 ether were required at 68, and 47 parts of boiling ether to 

 dissolve one of the acid. 



The melting point of the crystallized acid is 401. At that 

 temperature, if allowed to cool, it becomes solid, assumes a crys- 

 talline appearance, and becomes opaque. But if the temperature be 



