Vepys's Gas -holder* — Natural Thilofophy, &c. 40*7 



iron. A decompofition takes place, and there is produced a 

 muriate of zinc and the amalgam of iron and mercury, which 

 by kneading and the aid of heat aiTumes the metallic luftre. 



The fame gentleman along with Mr. Allen has obtained a 

 regulus of tungrten, from the ammoniate of that metal, the 

 fpecific gravity of which is above 17*22. It is of an iron 

 colour and of great brilliancy, but not malleable. 



MR. PEPYS's GAS-HOLDER. 



We find by a line from Mr. Pepys, that a note has been 

 omitted in printing his article in No. 50. It related to the 

 regilter tube, and mentioned, that U it was added to the gas- 

 holder on the fuggeftion of Dr. MarceL" 



NATURAL HISTORY. 



One of the French journals contains the following article :— - 

 6i Snakes have increafed this year fo much in number in the 

 large commons, that the proprietors of fheep have fuftained 

 great lofs by them. Thefe reptiles, particularly in the fpring, 

 luck the milk of the fheep; and when the wound which they 

 inflict is deep, the two teats dry up ; fo that the fheep, which 

 continue to be fruitful, can no longer fuckle their young. 

 But, when the wound is flight, the wounded teat only dries 

 up. In feveral of the communes of the department of Landes, 

 there are flocks, the fheep of which have been fucked by 

 thefe fnakes in the proportion of four to one." 



NATURAL PHILOSOPHY. 



ValTalli-Eandi, profeffor of natural philofophy in the 

 Athenaeum at Turin, has invented and caufed to be eon- 

 ftru&ed a pneumatic apparatus, with which all experiments 

 in regard to the rarefaction and condenfation of air, and all 

 kinds of aerial mixtures in given proportions, can be per- 

 formed in an eafy and fimple manner by means of piftons 

 and cocks. This machine has been depofited in the phylical 

 cabinet of Turin. 



INDEX 



