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11. Jnahjl'ical Experiments and Olservai'ions on Lac. 

 % Charles Hatchett, Esq. F.R.S. 



[Continued fiom our last volume, p. 358.] 



§IT. 

 Auahjtkal E.i/}cri/}icn/s on Stick, Seed, and Shell Lac. 



X-iAC, when placed on a red-hot iron, at first contract?, 

 and then melts, emitting a thick smoke, of a peculiar but 

 rather pleasant odour; alicr which, a light spongy coal 

 remains. 



Dist'/llat'/on of Stick Lac. 



.100 o-rains of the best stick lac, separated as much as 

 possible from the twigs, were put hi to a glass retort, to 

 which a double tubulated receiver and hydro-pneun)atic 

 api^aratus were adapted. Distillation was then gradually 

 performed, with an open fire, until the bottom of the 

 retort became red hot. 



The products thus obtained were, Gruins, 



1. Water slightly acid - - - 10. 



2. Thick brown butyraceous oil - - 59. 



3. Spongy coal - - - - 13.50 



4. A small portion of carbonate of ammonia, with 



a mixture of carbonic acid, carbonated hy- 

 drogen, and hydrogen gas, which may be 

 estimated at _ - - - 17.50 



100. 

 Seed Lac. 

 100 grains of very pure seed lac were distilled in a similar 

 manner, and alforded, 



1 . Acidulated water - - - G. 



2. Butvraceous oil - - - 61- 



3. Spongy coal , - - - - 7. 



4. ^lixed gas nearly as before, but without am- 



monia, amounting by estimation to - 2C. 



100. 

 Shell Lac. 

 100 grains o: shell lac, treated as above, yielded, 



] . Acidulated water _ . - 6, 



•2. Butyraceous oil _ _ _ 65. 



3. Spongy coal _ - - - 7,50 



4. Mixed gas, amounting bv estimation to - 21.50 



J 00. 



The 



