INDUSTRIAL PROGRESS DURING THE YEAR 1873. cxxix 



interest by all who give the subject of illumination even 

 passing attention. 



Several of the large depots of Vienna are illuminated, with 

 satisfactory results, upon the modified plan here described. 

 Open, unprotected flames, fed with oxygen, illuminate the en- 

 trance and exit galleries, and the vast interior of these build- 

 ings, with a light of exquisite mildness, brilliancy, and white- 

 ness of color, with none of the glare whicli, with the central 

 burners of the old plan, produced a painful impression upon 

 the eye. 



It is to be hoped that the success which the oxygen light 

 has met with in Vienna will stimulate its American advo- 

 cates to emulate so desirable a consummation. 



Another very decided advance in the field of illumination 

 is afibrded by the dynamo-electric machine of M. Gramme, 

 which, though for some time before the scientific W' orld, has 

 only during the last year attracted the attention which its 

 remarkable capabilities deserve.' The description of the ma- 

 chine belongs properly in our department of Physics, where 

 it will be found. The luminous efiects produced throuo:h its 

 instrumentality leave little to be desired. A large Gramme 

 machine, which was exhibited in London, produced a light 

 equal to about eight thousand candles, and still larger ma- 

 chines are being made which Mr. Crookes expects to give a 

 light equal to twenty-five thousand candles. 



A seeming solution of the problem of electrical illumina- 

 tion for city and domestic purposes, which shall avoid the 

 difticulty of the concentrated brilliancy, trouble of adjust- 

 ment, and complication of various forms of the electric light, 

 is furnished by Mr. A. Ladiguin, of St. Petersburg. The ma- 

 chine is driven by an engine, the luminous efiect being pro- 

 duced by a single piece of carbon, or other bad conductor, 

 connected with the machine, and placed in a glass tube ex- 

 hausted of air, filled with some gas which will not combine 

 with carbon at a high temperature, and then hermetically 

 sealed. The carbon is gradually and equably heated, and is 

 said to emit a soft, steady, and continuous light. One ma- 

 chine, driven by a three -horse -power engine, is said to be 

 capable of lighting many hundreds of such lanterns, which 

 Avill burn under water, and in mines as well as in the house. 

 Should the claims made for it prove to be literally true, the 



