1818.] their Combinations with Alkalies. 289 



tity ; whether it was really formed during the process, at the 

 expense of the fatty matter, or whether it was detached fixm 

 some substance which previously concealed its colour, it was 

 peculiarly developed by the action of potash. It was observed 

 that the process of saponification developed the leathery odour 

 which the substance had lost by fusion. 



3-6 parts of the coloured fatty matter, having been saponified 

 by an equal weight of potash, produced a soap which was decom- 

 posed by tartaric acid. 1. The aqueous Jiuid was distilled, and 

 the residuum was treated with alcohol. The alcohol dissolved 

 about 0-25 of a yellow syrup, the taste of which seemed at first 

 to be bitter and astringent, but afterwards became slightly sac- 

 charine. The product of the distillation had a slight smell of 

 leather and a little acidity ; being neutralized by barytes, 0*03 

 of a salt was obtained, which had rather the smell of delphinic 

 acid than of leather. 



2. The saponified fatty matter contained two substances, 

 which were easily separated from each other : the one which 

 was the most abundant constituted 3 - 06 parts ; it was of an 

 orange yellow colour ; the thermometer plunged into it, after it 

 was melted, fell to 79 - 5 c , and rose again to 82*6°. This sub- 

 stance, which was very soluble in the water of potash, appeared 

 to M. Chevreul to be entirely formed of the margaric and oleic 

 acids. The second substance, which constituted only 01 4 parts, 

 was brown, infusible at 212°, completely soluble in boiling alco- 

 hol, and left no fixed matter when it was incinerated. From this 

 experiment, 100 parts of the concrete matter contain 



Fatty saponified matter 88*9 



Matter soluble in water 1T1 



100-0 



The properties of the concrete substance which is separated 

 from the common fish oil seem to indicate that this substance 

 belongs rather to stearine than to cetine, or to the crystallised 

 substance which is obtained from the oil of the Delphinus. But 

 it is possible that this substance may not be essential to this fish 

 oil ; and besides, it exists in so small a quantity, that its nature 

 could not be very exactly ascertained. 



Upon the whole, we may conclude that the fish oil which was 

 examined resembles the oil of the Delphinus in its odour, but 

 that it differs from it, 1. In yielding ouly a trace of the volatile 

 oil after being saponified ; 2. In not furnishing any crystalline 

 substance analogous to cetine ; 3. In its being more easily sapo- 

 nin ed than that substance, and without producing any matter 

 which is not acid; 4. In containing much more of the colouring 

 principle. 



Besides the delphinic acid which exists in the oil of the Del- 

 phinus and in common fish oil, M. Chevreul thinks that we must 



Vol. Xll. N° IV. T 



