Messrs. Chamberlain & Hookham began, a few years ago, the manufacture of dynamos having permanent steel magnets, but they subsequently adopted the more usual type of electro-magnetic machines. Particulars are not to hand of this firm’s work, but the residences of Messrs. Walter Chamberlain and Herbert Chamberlain are amongst the examples of domestic electric lighting carried out by the firm, whose attention, however, has been directed principally to the manufacture of dynamos for electro-depositing purposes, where very heavy currents of low electro-motive force are required. The public supply of electricity was in 1882-3 the subject of much attention on the part of Messrs. Winfield & Crompton, under whose auspices the Incandescent Electric Lighting Co. Ld. was registered. An Act of Parliament was obtained, and plans and estimates were made by the writer for lighting a large district in Birmingham from central stations. Carefully collected statistics of the gas consumption in the proposed district afforded some interesting information, such as, for instance, that the average cost of gas per burner per annum, called the burner earnings, varied from 2d. to 43/6 per burner per annum, and showed a mean earning for the whole district of 10/2 per burner per annum, the average price of gas being about 2/3 per 1,000 cubic feet. From various causes, chief amongst them being the adverse restrictions of the Electric Lighting Act of 1882, the operations of the Company have remained in abeyance. The Birmingham Act is, however, still in force, and should the efforts which are now being made for the removal or substantial modification of the obnoxious clauses of the Act meet with the desired success, Birmingham may yet enjoy the advantages of a public supply of electric light, the luxury of which only those who have lived in an electrically lighted house can fully appreciate. =Flint Glass Manufacture of Birmingham.=--[A. C. OSLER.]--(B. 526.) Further inventions have been made with regard to furnaces. Frisby’s patent, the fuel inserted from below, instead of being thrown on the top of the fire, has met with some amount of favour, having been adopted by several Stourbridge houses. Bœtius’s patent, by which the earlier stages of combustion take place below the floor of the furnace, and a current of heated air is supplied to complete the combustion as the inflammable gases pass through an opening in its floor into the furnace itself, has now been in use at Messrs. Osler’s for many years. The process of etching by hydrofluoric acid, has been largely developed as a means of ornamenting glass, and has to a large extent superseded engraving. Highly artistic designs are produced by a combination of etching and engraving. Mechanical methods are adopted in producing many effective borders.