On Sea-Weeds as the sources of Acetic Acid. 25 



II. Twenty-four pounds of fresh Fucus nodosus, also in a moist 

 state, were suffered to ferment along with lime at a temperature 

 of 96° F. for about five weeks. Twenty ounces of crude acetate 

 of lime were obtained, which, when distilled with hydi-ochloric 

 acid, yielded 57 oz. of pretty pure vinegar, each ounce of which 

 saturated 43 grs. of anhydrous carbonate of soda. The amount 

 of the acetic acid in the whole quantity was therefore 2451 grs. 

 = 1'45 per cent, of the wet Fucus nodosus. 



III. Four pormds of fresh Fucus vesiculosus were left to fer- 

 ment in the open air along with quicklime, at the ordinaiy tem- 

 peratm-e, from the 8th of Jime to the 1st of September, when 

 the process was finished. The filtered solution of the acetate of 

 lime, after being evaporated to diyness, when distilled with hy- 

 di'ochloric acid, yielded 46 oz. of weak vinegar, each ounce of 

 which saturated 7 grs. of anhydrous carbonate of soda, amount- 

 ing therefore in all to 322 grs. of anhydi'ovis acetic acid =1*15 

 per cent, of the wet sea-weed. Tlius it is clear that when sea- 

 weeds are fermented at the ordinary temperature of Scotland, 

 during the summer months the process goes on much more 

 slowly, and yields a considerably smaller product than when the 

 temperature is retained at about 90° F. Should any person, 

 therefore, think of manufacturing acetic acid from sea-weeds, 

 either in Great Britain or in any of the northern countries of 

 Eui'ope, I would advise him to employ so much artificial heat as 

 to produce a constant temperature of from 90° F. to 96° F. I 

 should expect, however, that in the southern portions of Europe, 

 at least during the summer months, and in tropical countries, 

 artificial heat might probably be dispensed with. 



One of the chief uses to which sea-weeds are applied is in 

 manm-ing land; and with this application, then- having been 

 pi'eviously employed in the manufacture of vinegar would not 

 veiy materially interfere. For if the femiented weeds and the 

 salts remaining in the stills were spread upon the land, I ap- 

 prehend they would prove almost as useful in an agricultural 

 point of view as the fresh sea-weeds would have done. 



The vinegar obtained from the Fuci contained a very minute 

 quantity of butync acid. When it was therefore saturated vnih 

 carbonate of soda, evaporated to diyness, and the dry salt left 

 for some time in a moist atmosphere, a small portion of it deli- 

 quesced. This liquid portion was therefore separated from the 

 solid salt and was evaporated to dryness. It formed a sapona- 

 ceous looking, unciystallizable mass, which had the peculiar 

 odour of tlie butyrates ; and when it was digested with a mixture 

 of alcohol and sulphuric acid, yielded an lether which had the 

 characteristic odour and.propertics of butyric a>ther. A silver 

 salt, prepared from this supposed butyrate of soda by double de- 



