which it necessitates. Another chemist, Mr. Specht, even in 1860 decomposed Al2C16 by zine, and has the same report to make that he thinks the process will be some time advantageously practised on a large scale."

However, this method has not succeeded in being established in practice, probably on account of the high temperature which is necessary to drive off the zinc, in which operation some aluminium is lost.

Kagensbusch,* in Leeds, makes the singular proposition to melt clay with fluxes; then, by adding zinc or lead, to decompose it by an electrical current and isolate an aluminium-zinc or aluminium-lead alloy, from which the zinc may be volatilized or the lead cupelled.

Mr. Fred. J. Seymourt patents the reduction of aluminium by zinc, and makes the following claim: An improvement in extracting aluminium from aluminous earths and ores by mixing them with an ore of zinc, carboniferous material and a flux, and subjecting the mixture to heat in a closed retort, whereby the zinc is liberated, is caused to assist in bringing or casting down the aluminium in a metallic state, and an alloy of aluminium and zinc is obtained.

The only information outside of the patent claims

* Eng. Pat., 1872, No. 4811.

U. S. Pat., No. 291,631, Jan. 8, 1884.

which I could find in regard to this process is contained in the following newspaper article, which, although wordy and indefinite, will have to be taken in the absence of a more precise account.

"Mr. F. J. Seymour,* a well-known practical metallurgist, late of Bridgeport, Conn., has, as the result of several years' study, succeeded in producing aluminium at a low cost, and by the novel furnace just designed asserts that he can extract the metal on a commercial basis in large quantities. Not to go into all the technical details, which are extremely interesting to metallurgists, it is sufficient to say that Mr. Seymour has discovered that the close affinity existing between aluminium and zinc can be utilized in vaporizing, capturing, and depositing the aluminium, the separation being effected by the aid of heat in a furnace, or rather a series of furnaces, of peculiar construction. The charge for each furnace is zinc ore 100 parts, koalin 50, carbon (either anthracite coal or its equivalent in hydrocarbon gas) 125, pearl ash or its equivalent 15, NaCl 10; all intimately mixed. The retorts are of steel, 36 inches long, 12 inches diameter, sides inch thick. The heat necessary to produce the result is about 2500° F., or 1400° C. Properly handled, one furnace should make two charges in 24 to 30 hours. Four men can operate 50 retorts.

Cleveland Letter to the New York Times,' April 14,

The number of retorts can be increased to several hundred in a single system. Capitalists are already interested in this new process, and the prospects are that operations on an extensive scale will soon follow. Independent investigations in the same line in this city have resulted in the recent incorporation of a company for the extraction of aluminium by electricity. Thus far the secret of the process has been strictly guarded, and no details can be given."

Mr. Seymour has quite recently taken out another patent, the claims of which are hardly reconcilable with those of the former patent. The claim is as follows:

:

Patent to Fred. J. Seymour,* Wolcottville, Conn., assignor of one-half to Mr. Henry Brown, New York. The following is the claim: "The process of extracting aluminium from aluminous earths, consisting in subjecting such ore or earth with an ore of zinc, carbonaceous matter, and a flux, to heat, in a retort; wherein the oxides of aluminium and zinc are vaporized; collecting and condensing the vapors in a condenser, and afterwards subjecting the condensed product to heat with carbonaceous matter, substantially as herein described."

If Mr. Seymour can make a process work according to the details of the above extraordinary claim,

* U. S. Pat. No. 337,996, filed March, 1885, granted March 16, 1886.

he will certainly have a claim on the admiration of all scientific men. The idea of vaporizing the oxides of zinc and aluminium is certainly unique. I wrote to Mr. Seymour, asking for further details of his process, and if he was making any aluminium, but have received no further information than has already been given.

6

The American Machinist,' August, 1886, contains the statement that the American Aluminium Company has been organized at Detroit with a capital stock of $2,500,000; to use the patents of Dr. Smith for the United States, Great Britain and France. I was informed by a gentleman in the aluminium industry that this company were to operate Mr. Seymour's zinc process.

REDUCTION BY LEAD.

According to the invention of Mr. A. E. Wilde,* of Notting Hill, lead or sulphide of lead, or a mixture of the two, is melted and in a molten state poured upon dried or burnt alum. The crucible in which the mass is contained is then placed in a furnace and heated, with suitable fluxes. The metal, when poured out of the crucible, will be found to contain aluminium. The aluminium and lead can be subsequently separated from each other by any known means, or the alloy or mixture of the two metals

* Sci. Am. Suppl., Aug. 11, 1877.

can be employed for the various useful purposes for which lead is more or less unsuited.

Kagensbusch's process, using lead, is described on p. 218 under the reduction by zinc.

REDUCTION BY MANGANESE.

W. Weldon,* of Burstow, Eng., claims to melt together cryolite with CaCl2 or another non-metallic chloride or sulphide, and then to reduce the Al2C16 or A12S produced with manganese, which he claims is even powerful enough to reduce sodium.

REDUCTION BY ELECTRICITY.

The reduction of Al2C16 or Al2C16.2NaCl by sodium is the only process by which the pure metal is now made. However, many attempts have been made to isolate it by means of the electric current. The reduction may take place in either the dry or wet way. The reduction of fused A12C16.2NaCl by the battery was accidentally discovered simultaneously by Deville in France and Bunsen in Germany, in 1854, and is nothing else but an application of the process already announced by Bunsen of decomposing magnesium

* Eng. Pat., 1883, No. 97. Wagner's Jahresb., 1884.