Mr. J. Glaisher on the Meteor of February 11, 1850. 221 



The formula of the non salt, dried at 212°, would there- 

 fore be j,^5 ^y 12 3 j^Q p^5 ^ g ^Q 



Nitroprusside of Zinc. 

 17. This salt is prepared by precipitating one of the soluble 

 salts of zinc by a nilro-prusside. It is a salmon-coloured 

 precipitate, of a more fleshy colour than the iron salt. When 

 formed slowly, as when muriatic acid and zinc are made to act 

 on nitroprusside of soda, it is of a deep orange colour. 



Nitroprusside of zinc is very slightly soluble in cold water, 

 rather more so in hot water. In its behaviour to reagents it 

 acts exactly like the iron nitroprusside. It was analysed by de- 

 composing it with sulphuric acid, separating the iron by suc- 

 cinate of ammonia and determining the zinc as a carbonate. 



I. 24-14 grs. gave 6*92 grs. peroxide of iron and 670 grs. 

 oxide zinc. 



9-43 grs. gave 7*10 grs. carbonic acid and 0-335 gr. water. 



Calculated. 



Iron 20-07 5 140 20-11 



Zinc 22-26 5 160 22-98 



Carbon . . . 20-53 24 144 20-69 



Hydrogen . 0-39 2 2 0-28 



100-00 696 100-00 



This analysis would lead to the formula 

 FeSCy^2 3NOZN5 + 2HO. 



[To be continued.] 



XXVIII. On the Meteor iiohich appeared on Mofidai/^ the 1 1th 

 of February 1850, at about 10^ 45"^ P.M. By James 

 Glaisher, Esq., F.R.S. 



To the Editors of the Philosophical Magazine and Journal. 

 Gentlemen, 



THE magnificent meteor which was seen all over England 

 on the night of February 11, 1850, was so remarkable 

 in many respects, that I beg to send you the following par- 

 ticulars of it. 



