hitelligence and Miscellaneous Articles. 231 



Thomson Cr CloV or Cr O^i CI 



Wdhler Cr G\ + 2 Cr Oo| 



Dumas Cr CI3 



Rose Cr CI + 2 Cr Oo^j 



There is an error also in the description of the properties of this 

 compound. Chloro-chromic acid does not detonate with phosphorus 

 unless that substance is moistened with water. 



Your obedient servant, 



June 29th, 1838. P. 



FALL OF METEORITES IN SOUTH AFRICA. 

 " I have forwarded to Sir J. Herschel a splendid specimen of a 

 meteor that exploded about 100 miles from Cape Town. The whole 

 mass could not be less than 4 cubic feet. A pretty sort of solidifi- 

 cation if it took place in our atmosphere ; such an origin is scarcely- 

 conceivable. You will no doubt hear of it from him, together with 

 its analysis*. We were at tea last Wednesday evening {&^ 37") 

 broad daylight, when a meteor passed over the Observatory from 

 the N.W., and appeared to fall a few hundred yards in front. We 

 simultaneously jumped up. It was as brilliant as a full moon, but 

 a more pungent X\^X,; no noise. The image of the window-sash 

 upon the opposite Avall was as bright as if the sun shone in front 

 of it. The apparent size of the body was equal to that of a full 

 mo^jn."— Extract from a letter {November 25, 1838) from Thomas 

 Maclear, Cape Town, to Captain Smyth, R.N. 



ALLOXANf. 



The erythric acid of Brugnatelli ; rediscovered by Wdhler and 

 Liebi'^. One of the products of the decomposition of uric acid 

 by nitric acid. One part of dry uric acid is added in successive por- 

 tions to 4 parts of nitric acid of sp. gr. 1'45 to 1-5, by which it is 

 dissolved with effervescence and the production of heat ; the pro- 

 duction of a high temperature must be avoided as much as possible 

 by artificial cooling, and by adding the uric acid slowly. Small 

 granular crystals of a strong lustre are thus formed, and by degrees 

 the whole liquid is converted into a solid mass. This should then 

 be placed in a glass funnel; and after the fluid parts have thus 

 drained oif, it should be spread upon a porous tile, where it is ren- 

 dered perfectly dry. It is purified by solution in hot water and re- 

 crystallization. 



Properties. — On the cooling of a warm but not perfectly saturated 

 solution of alloxan, it is obtained in large colourless and transparent 

 crystals of the right prismatic system, and of a strong adamantine 

 lustre ; these crystals eflioresce rapidly, losing 2-5 per cent. =6 eq. 

 water, and are converted when gently warmed, with the loss of 



• From a letter received, togetlier with a specimen of the meteorites, from 

 Mr. George Thompson, of Cajje Town, the date of the fall appears to have 

 been October 1.!, 1H3S.— K.W.B. 



■j 'J'his and the seven following notices are copied from Part FlI. of the 

 late Dr. Turner's Chemistry, recently published by Professor Liebig and 

 Dr. Wilton Turner. 



