1815.] Scientific Intelligence. 155 



which have a crystallized appearance, and which at Canton are 

 called cho yeip, or bamboo leaf, from their resemblance to that leaf, 

 are formed from tin in the same way. They are not made in the 

 neighbourhood of Canton. 



IX. Haiiy's Crystallography. 



It gives us great pleasure to state, that Mr. Larkins, N° 14, Gee 

 Street, Somer'sTown, has commenced teaching the mathematical 

 part of Haiiy's theory of crystallization. It is scarcely necessary to 

 observe, that without a correct knowledge of the mathematical 

 principles from which this most beautiful theory has been deduced, 

 very little progress can be made in the study of crystals. Mr. 

 Larkins has likewise cut in wood very beautiful models of all the 

 crystals described by Haiiy in his System of Mineralogy. Complete 

 sets of these models are sold at the rate of from thirteen pounds to 

 fifteen pounds sterling, according to the kind of wood from which 

 they are cut. 



X. Table of Temperatures. 



M. Guyton Morveau has been employed for many years in con- 

 structing a pyrometer of platinum to measure the higher degrees of 

 heat. He was induced during his experiments to compaie it with 

 the mercurial thermometer, and with Wedgewood's pyrometer. 

 The following table * exhibits the result of his experiments. 



Mercury melts . . » . . . 



Water freezes 



Water boils 



Bismuth melts 



Tin melts 



Lead melts 



Mercury boils 



Zinc melts 



Antimony melts 



Silver melts 



Copper melts 



Gold melts 



Welding point of iron 



Cast-iron melts 



Porcelain melts 



Manganese molts . . . . 

 Macquer's furnace . . . 

 Fourneau a trois vents 

 Malleable iron melts . 



Nickel melts 



Platinum melts 



Degrees of 

 ■Wedgewood. 



oo 

 3 



7 



27 



32 



95 

 130 

 155 

 160 

 1C5 

 170 

 175 



175 + X 

 175 +x 



Degrees of Fahrenheit. 



-39° 

 + 32 

 212 

 475-99 

 512-48 

 CI 1-98 

 642*75 

 705 -2G 

 955-25 

 1822-67 

 2205-15 

 25 1 7-63 

 650S-88 

 8696-24 

 9633-63 

 10517-12 

 10829-60 

 1 1 142-08 

 11454-56 

 11454-56 + X 

 11454-56 + X 



* Aiuialci dc Chimic, it, I'i^, 



