JOURNAL 



OP 



NATURAL PHILOSOPHY, CHEMISTRY, 



AXD 



THE ARTS. 



NOVEMBER 1797, 



ARTICLE I. 



Experiments m,d Obfervatiom on the Nature of Sugar. By IVilliam Cjiuickshjnk, Chevujl 

 to the Ordnance, and Surgeon of Artillery. 



OUG AR has been fuppofed to be a fubftance intermediate between mucilages and ve- 

 getable acids, containing more oxygene than mucil.ge, and lefs than the acids. To afeertain 



tins and fome other circumftances, the following experiments were inftituted • 



Two ounces of refined fugar were introduced into a retort, and expofed to a heat gra- 

 dual y mcreafed until its bottom became red-hot : there came over into the receiver feve,,- 

 drachms of a fliarply acid liquor, which required .32 grains of a folution of pot-afii to h- 

 turnte it: this liquor was mixed with a Httle empyreumatic oil: the charry refuluum 

 which remained in the retort weighed feven drachms ; the quantity of gas which efcape.l 

 during the operation muft tlierefore have amounted to two drachms : fome of this was ex 

 amined, and found to confifl of a mixture of carbonic acid gas and hydro-carbonatc 



Two ounces of gum-arabic were introduced into a retort at the flime time, and cxpof.d 

 to a heat in every refped fimilar : the quantity of acid liquor which came over into the re. 

 ce.vcr amounted to feven drachms and 15 grains ; this contained a little more empyreu- 

 matic 0,1, but was not fo fliarp as that obtained from the fugar, and required only , r^lrain. 

 of the fame foution of pot-a,h to faturate it: the charry refiduum which remained hi ,hc 

 retort weighed five drachms and 45 grains; the quantity of elaftlc ftuld or gas which cf- 

 caped during this proccfs muft therefore have amounted to three drachms: it confided 

 like the former, of a mixture of hydro-carbonate and carbonic acid gas; but towards thJ 

 end of the operation the proportion of hydro-carbonate was more remarkable. From thefe 

 experiments It would appear that fugar yield, by diftillation more pyromucous acid thair 



VOL. I. NOVEMBEU 1707. Y V 



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