Chemical Science, 225 



fourth of its bulk, and have a specific gravity of 0.8. The bladder 

 of an ox or a calf is to be used, prepared by being steeped some time 

 in water, washed, blown out, freed from fat and adhering vessels, 

 the two ureters effectually tied, and then turned inside out, that 

 both sides may be cleansed. Being then blown up and dried, the 

 surfaces are covered with a solution of isinglass ; one layer is put 

 upon the internal surface, and two upon the exterior. The texture 

 thus becomes closer, and the alcoholic concentration proceeds 

 better. 



The bladder should not be filled, but a small space left. It does not 

 become moist to the touch, and allows no odour of alcohol. If the 

 alcohol have a greater specific gravity than 0.952, the bladder softens 

 and feels moist. Bladders prepared as above, may be used a hundred 

 times or more : they gradually acquire a yellow brown colour and 

 become stiff, but they are improved by a slight change. The air- 

 vessel of the salmon will not produce these effects : alcohol of spe- 

 cific gravity 0.856 being put into one for 32 hours, lost a third 

 of its volume, and was very much weakened. The air-bladder did 

 not become moist, but the odour of alcohol was perceived near it. 



Weak alcohol in bladders lost its water more rapidly than stronger 

 spirit. In an experiment between water and alcohol, two equal 

 bladders were chosen, and eight ounces of water put into one, whilst 

 eight ounces of alcohol were put into the other. Both were equally 

 exposed to a moderate heat : in the course of four days all the water 

 had disappeared, whilst the alcohol had lost only one ounce of its 

 weight. 



If artificial heat is properly employed, absolute alcohol may 

 be obtained in from 6 to 12 hours. Even solar heat will produce 

 absolute alcohol. 



Wine put into the prepared bladders acquired no bad odour ; it 

 took a deeper colour, had more aroma, a milder taste, and generally 

 became stronger. Oil of turpentine, put into a jar and covered by 

 a bladder, lost nothing in four years. Concentrated vinegar lost 

 half its volume in four months ; the other half was thick, and had no 

 acid taste. Orange-flower water, under the same circumstances, lost 

 a third of its bulk in several mouths, but had acquired a stronger 

 odour, and had evidently lost none of its volatile principle. — Menu 

 de Munich, ix. 103. — Bull. Univ. A. ix. 322. 



45. Formation ofAdipocire. — Dr. Harlan of Philadelphia relates, 

 that having occasion to macerate a cranium in the summer of 1824, 

 he directed the head of a large fat negro, who had died of acute 

 fever, to be placed in a barrel half filled with water and closely 

 covered over. On examining the process about six weeks after- 

 wards, he was surprized to observe the head floating buoyantly on 

 the surface of the water, lying on one side. The gas disengaged 

 during putrefaction, and detained within the cranium, had probably 

 produced this effect. The upper surface, or that which floated 

 above the water, presented a tumid appearance, and on cutting into 



JULY—SEPT. 1828. Q 



