1 02 Dr. L. Playfair on a new Fat Acid 



at Cramlington, is sufficiently obvious : it appears by the ac- 

 counts given, that it was necessary for the water to be satu- 

 rated to such a degree as to have a deposit formed on the side 

 of the boiler ; that a high temperature is requisite as the ma- 

 chine is a high-pressure one ; that the electricity increases 

 with the deposit, and that it varies with the temperature. 



This phaenomenon only appearing when there is a saline 

 coat deposited, and its tension increasing with the thickness 

 of the layer, it will serve to make known the degree of in- 

 ternal incrustation and the sudden variations of temperature. 



XX. On a new Fat Acid in the Bidter of Nutmegs. By 

 Lyon Playfair, Ph. Z).* 



npHE butter of nutmegs has been the subject of several ex- 

 *- aminations; for the best account of its properties, how- 

 ever, we are indebted to Schrader, This chemist has shown 

 that it is a compound of three oils, two of them being solid, 

 the other volatile and liquid. He has also examined the pro- 

 portional quantities of these, and described the methods by 

 which they might be separated from one another. 



Lecanut observed that this butter possessed different pro- 

 perties from other vegetable fats, and approached more nearly 

 in character to those of animals. He remarked likewise its 

 partial solubility in aether, which had formerly been pointed 

 out by Schrader as a distinguishing mark. 



Pelouze and Boudet J described a method by which mar- 

 garine could be procured in a state of purity, and mentioned 

 that the same margarine existed in the butter of nutmegs ; 

 but they have given no experiments in proof of this, nor did 

 they state analyses of the products obtained. 



None of the chemists now mentioned have published the 

 numerical results of their examinations. Hence it was uncer- 

 tain whether the acid existing in the butter of nutmegs was 

 really margaric acid, or some other acid resembling it in pro- 

 perties. It was interesting to ascertain the exact composition 

 of this margarine,, and for this purpose the following examina- 

 tion was undertaken. 



When the butter of nutmegs is digested with alcohol of 

 the common strength, it is decomposed; the alcohol dissolves 

 a coloured fat, acquires a wine-red colour; and yields by 



* Communicated by the Autlior ; liaving been read before the Britisli 

 Association at the late meeting at Glasgow, 

 t Journal de Pkarmacie, t. xx. p. 339. 

 X Annalet de Chimit et de Phj/sique, t. Ixix. p. 47. 



