450 Miscellaneous Intelligence. 







also referred to, as being in the possession of Dr. Kersh, abstracts of 

 whose correspondence, as well as a letter from Mr. McKeown, will be 

 presented hereafter in my description of this iron. 



I have already ascertained that it contains about 5 p. c. of nickel, 

 besides traces of chromium, cobalt, and nodular masses of magnetic 

 pyrites, which latter substance, when dissolved, exhibits fine, but very 

 brilliant scales of plumbago. 



lis most remarkable peculiarity consists in the appearance of its pol- 

 ished surfaces when treated with dilute nitric acid. In one spot, it then 

 shows scattered, but distinct characters, resembling Chinese letters ; in 

 another at wide intervals, a series of short, straight lines, with square 

 ends, precisely like dashes in printing; again the brilliant markings 

 are arranged across an uniform ground, so as to simulate the course of 

 a river on a map, or the meshes of a cobweb. The spaces between 

 the raised lines above described are filled up with shining points and 

 fine Widmannstattian figures, presenting on the whole, a surface strik- 

 ingly similar to that produced in silver when cooled from fusion. It is 

 very dense, and takes a brilliant polish ; but its etched surface imme- 

 diately distinguishes it from every other iron hitherto described. 



2. Staile's Electric Light. — We have just received in the Mechanics 

 Magazine, the specification in full of Mr. Staite's patented improve- 

 ments in the production of galvanic light for illumination. 



The question of the economical and successful application of gal- 

 vanic light to the purposes of general illumination, has of late excited 

 considerable interest, and some brief notices of Mr. Staite's labors on 

 this subject have already appeared in the public prints. 



One of the principal difficulties in the way, has been the inconstancy 

 of the light of the carbon points or electrodes used, in consequence of 

 the variations in the strength of the current. This difficulty Mr. Staite 

 has endeavored to overcome, how successfully remains to be seen, by 

 means of mechanism for regulating the interval between the carbon 

 points. This he has done in various ways, one of which, we believe, 

 was specified in a former patent granted in July, 1837. One of the 

 simplest specified in the present patent, and that by which we can best 

 illustrate the operation of the others, consists in connecting the lower 

 or negative carbon point or electrode with an iron rod or bar moving 

 vertically in a coil of wire, through which the galvanic current is made 

 to circulate. The iron rod rises by a counterpoise till it brings the car- 

 bon point connected with it, into contact with a fixed carbon point above, 

 when the current instantly passes and the coil acts on the iron rod and 

 draws it down and thus separates the two points, and continues to sepa- 

 rate them until the current is reduced to a standard quantity, deter- 

 mined by the weight of the counterpoise. If the current begins to fail, 

 the diminished action of the coil allows the counterpoise to bring the 

 points nearer together ; if the points approach too near, the current 

 becoming stronger immediately separates them again. To prevent 

 injurious vibrations or sudden movements of the iron rod, it is furnished 

 with a rack, wheel work and fly. 



Another improvement consists in giving the upper electrode the form 

 of a circular disc, made to revolve slowly in contact with a fixed scra- 

 per which keeps the edge of the disc clean and free from the particles 

 of carbon projected upon it from the lower electrode. 



