1889.1 Sir Henri/ Hoscue on Ahiiuinium. 451 



WEEKLY EVENING MEETING, 



Friday, May 3, 1889. 



Sir Frederick Bramwell, Bart. D.C.L. F.E.S. Honorary Secretary 

 aud Vice-President, in tlie Chair. 



{Sir Henry Eoscoe, M.P. D.C.L. LL.D. V.P.K.S. 



Aluminium, 



Chemists of many lands have c(mtributed to our knowledge of the 

 metal aluminium. Davy, in 1807, tried in vain to reduce alumina by 

 means of the electric current. Oerstedt, the Dane, in 1824, pointed 

 out that the metal could be obtained by treating the chloride with an 

 alkali metal ; this was accomplished in Germany by Wohler in 1827, 

 and more completely in 1845, whilst in 1854, Bunsen showed how 

 the metal can be obtained by electrolysis. But it is to France, by the 

 hands of Henri St. Claire Deville, in the same year, that the honour 

 belongs of having first j^repared aluminium in a state of purity, and of 

 obtaining it on a scale which enabled its valuable properties to be re- 

 cognised and made available, and the bar of "silver-white metal from 

 clay," was one of the chemical wonders in the first Paris Exhibition of 

 1855. Now England and America step in, and I have this evening to 

 relate the important changes which further investigation has effected 

 in the metallurgy of aluminium. The process suggested by Oerstedt, 

 carried out by Wohler, and modified by Deville, remains in princi23le 

 unchanged. The metal is prepared, as before, by a reduction of the 

 double chloride of aluminium and sodium, by means of metallic 

 sodium in presence of cryolite ; and it is therefore not so much a 

 description of a new reaction as of improvements of old ones of which 

 1 have to speak. 



I may perhaps be allowed to remind my hearers that more than 

 33 years ago, Mr. Barlow, then secretary to the Institution, delivered 

 a discourse, in the presence of M. Deville, on the 2)roperties and mode of 

 j)reparation of aluminium, then a novelty. He stated that the metal 

 Vs as then sold at the rate of 3/. per ounce, and the exhibition of a small 

 ingot, cast in the laboratory by M. Deville, was considered remarkable. 

 As indicating the jDrogress since made, I may remark that the metal 

 is now sold at 20s. per lb., and manufactured by the ton, by the 

 Aluminium Company, at their works at Old bury, near Birmingham. 

 The improvements which have been made in this manufacture by the 

 zeal and energy of Mr. Castner, an American metallurgist, are of so 

 important a character, that the process may properly be termed the 

 Deville-Castner process. 



The production of aluminium previous to 1887, probably did not 

 exceed 10,000 lbs. per annum, whilst the i>rice at that time was very 



