Salt to Fresh Water. 243 



-f Horse mackerel Crabs 



f Pollack + Oysters 



Prawns + Muscles. 



Shrimps 



There appears no reason why turtle should not also be culti- 

 vated, whether they would breed or not. The peacock, pintado, 

 pheasant, and common fowl, are the natives of hot climates, and 

 have long been naturalized to cold ones ; and there is far less dif- 

 ference between the temperatures of the water in different cli- 

 mates than between those of the air. An excellent turtle has 

 been taken in the Tamar at Saltash, after an unknown length of 

 residence. 



ART. X. On the Impurity of the* Pulverized Emetic Tartar 

 of the Shops. 



[In a Letter to the Editor of the Quarterly Journal.] 

 SIR, 



I AM induced to request your insertion in the Quarterly 

 Journal of the following facts, with regard to emetic tartar. Hav- 

 ing repeatedly noticed a portion of insoluble matter in making the 

 vinuna antimonii tartarizati, I purchased some tartar emetic in 

 crystals, and much to my astonishment was charged nearly double 

 what I had previously paid for it in powder. I procured samples, 

 from several respectable druggists, and found in all cases the same 

 inconsistency in price. Upon careful examination, however, of 

 the powder, this was explained, for I found in all the samples, 

 after the triple tartrate had been carefully washed out by cold 

 water, at least ten per cent, and in two or three much more, of a 

 powder comparatively insoluble, and which proved to be princi- 

 pally supertartrate of potash and tartrate of lime. I strongly sus- 

 pect the manufacturers are in the habit, after boiling the tartar 

 with the oxide of antimony and filtering, of evaporating immedi- 

 ately to dryness that portion which is to be sold in powder ; this 

 will explain its impurity, and also its cheapness, when compared 

 with that which has been carefully crystallized. As uniformity 



