20 Messrs. Buckton and Odling on Aluminium Compounds. [Jan. 12, 



siderable interest from the bearing it would necessarily have upon the posi- 

 tion of aluminium in a natural classification of the elements ; upon the 

 molecular formulae of chromic, ferric, cuprous, and perhaps mercurous 

 compounds j and consequently upon Laurent and Gerhardt's general law of 

 even numbers. Moreover a satisfactory investigation of the organo- 

 compounds of a metal certainly not belonging to any one of the recognized 

 classes of metals with whose organo-compounds chemists have become 

 familiar, seemed likely to furnish a useful contribution to the common know- 

 ledge of organo.metallic bodies. Cahours, in an admirable paper on the 

 organo-compounds of tin, published early in 1860, observed incidentally 

 that aluminium was attacked by the iodides of methyl and ethyl at the 

 temperatures 100-130, and that the crude ethylated product reacted 

 violently with zinc-ethide to form a very inflammable liquid, which was 

 doubtless aluminium ethide. Our experiments in confirmation of Cahours's 

 results have been as yet merely preliminary ; but by acting on aluminium 

 with mercuric methide and ethide at the temperature of 100, we have ob- 

 tained pure aluminium methide and ethide without difficulty, and in not 

 inconsiderable quantity. This mode of experiment was obviously suggested 

 by Frankland and Duppa's recently described processes for making methide 

 and ethide, and for transforming these compounds into zinc methide and 

 zinc ethide respectively. 



Aluminium Ethide. 



Mercuric ethide with excess of aluminium-clippings contained in sealed 

 tubes was heated for some hours in a water-bath, when the mercury was 

 found completely displaced by the aluminium, thus, 



A1 2 + 3 Hg Et 2 = Hg 3 + 2A1 Et 3 , or AL, Et 6 . 



After distillation off fresh aluminium and rectification in an atmosphere of 

 hydrogen, the resulting aluminium ethide boiled steadily at 194. It 

 occurred as a colourless mobile liquid, which did not solidify at u the tempe- 

 rature of 18C. It evolved dense white fumes on exposure to air, and 

 when in thin layers took fire spontaneously, burning with a bluish red- 

 edged flame, and producing an abundant smoke of alumina. On analysis 

 it yielded 61 '4 per cent, of carbon, 12'9 per cent, of hydrogen, and 24-0 

 per cent, of aluminium, numbers which accord reasonably well with the 

 formula Al Et 3 , or A1 2 Et e , the carbon and hydrogen being slightly deficient 

 from some unavoidable oxidation of the substance analyzed. Its vapour- 

 density, taken by Gay-Lussac's process at the temperature 234, was found 

 to be 4-5, the theoretical density calculated for the formula AlEt 3 being 

 3'9, and that for the formula Al 2 Et 6 being of course 7'8. Hence alumi- 

 nium ethide would appear to have the simple molecular formula Al Et 3 ; 

 for the difference between the experimental number 4*5 and the theoretical 

 number 3*9, is an obviously necessary consequence of the extreme oxidiza. 

 bility of the compound. Water effected a complete decomposition of alu- 

 minium ethide with explosive violence. Iodine reacted upon it, to produce 

 iodo-derivatives and iodide of ethyl. Oxygen in the form of dry air was 

 simply absorbed with production of a body apparently analogous to boric 



