Improvement in Confstruction of Smelting: Furnaces. Messrs. Editors:—As a reader of your excellent journal I have been much interested in the various articles published DU the manufacture of iron, steel, etc. My object in writing to you is to call attention to the man-afacture of pig iron, and to get information and suggestions. [ believe there is yet much improvement to be made, but not iltogether in the direction now generally pursued. If I am right, the principal improvements of late consists Lu building the stack much higher than formerly, in order to utilize the heat and more thoroughly prepare the stock for melting; second, to greatly increase the temperature of the blast, in order to perfect the melting when the stock arrives it the pi oper point, or " bone," as I believe it is called. I have been engaged in melting iron in a cupola for a number of years, and for the past two years have changed the construction of the inner walls of the cupola and tweers, and for the past twelve months have accomplished much in utilizing the heat, and have consequently made a large saving Df fueh We use ninety graduated tweers in a cupola 36 in in diameter. This arrangement thoroughly distributes the blast through the coke in place of chilling it, as it does in the ordinary way. I am not aware that this plan has been tried in a blast furnace, although various patents have been granted. No patent, however, has been allowed for this specific arrangement or thing like it. If it could be used, and the same result attained in the manufacture of pig iron it would be a very important advance in the right direction. It is the opinion of practical men that it can be, and the hot blast dispensed with, but with the hot blast perhaps better results would be obtained. 1 send the result of one day's work, and although it is somewhat better than the average year's work, it is not materially so. cke. I IRON. No. of No. ot charges. Total, charges. Total, lor bed.........................1,400 1................................ 5,000 2 of 120 lbs. each............... 240 2 of 1,000 lbs. each.............2,000 19 of 100 lbs. each..............VOO 19 of 1,000 lbs. each.............19,C00 6 of 80 lbs. each................ 480 G of 1,000 lbs. each............6,000 40 32 Coke returned not burned...... 875 Iron returned not melted..... 462 Coke actually burned...........3,145 | Iron actually melted..........31,538 One pound of coke melted ten pounds of iron. Loss in melting, two per cent. Amount of limestone charged per tun, 50 pounds. Size of cupola across the tweers, 36 inches. Size of cupola above the tweers, 48 inches. Hight to charge hole, 13 feet. Two cylinders, each 36 inches in diameter, 30-in. stroke. No. of revolutions per minute, 60. Cubic feet of air per minute, 4,241. Time in melting, 1 hour and 40 minutes. Cincinnati, Ohio. R. A Recommendation to " Many Farmers." Messrs. Editors :—In a recent issue of the Scientific American, my attention was drawn to the request of " Many Farmers," for an invention that would enable them to utilize waters running through their lands to waste while their corn crop is suffering by drought. To my mind it seems that if Many Farmers " would club together and purchase one of the steam engines now in nse to extinguish fires, they might draw the water from a considerable distance and throw showers over their fields at pleasure. These machines are portable aad readily conveyed from one distant point to an Dther, and if expensive at first,their utility would soon cover the cost, and the annual interest on the sum invested would be less than ditching, or pipes, etc. In the same issue a substitute is wanted for the present cruel " method of branding cattle." It occurred to me that a chemical co:?ipound could be employed ; say. Quicklime, 1 oz. ounce ; niter, J ounce ; orpiment, 3 drachms ; sulphur 1 drachm ; soap lees, 4 ounces, mixed and evaporated to a proper consistence to print with, or lime and water mixed to a thick cream, and passing through the mixture 25 or 30 times its volume of sulphureted hydrogen gas till the gas begins to escape, then stop the process. This pulpy mass laid on tho hair for 12 or 15 minutes, then washed off with a sponge, will remove the hair as well as burning. The rain might do tho washing off. Perhaps this may suggest to your own prolific minds a still better compound. J. Stauffer, Lancaster, Pa. The Premium Offered on a Time and Percussion Fuse Iy tlie Swiss Government. Messrs. Editors :—The Swiss Government, according to statements made in the Swiss newspapers, offers a premium of 2,0C0 in gold for the best time and percussion fuse for shells, and names Oct. 1st, 1869, when models are to be presented to the military department at Berne. Inventors would like to know—First, is the notice official ? Second, are inventors of all nations invited to compete? Third, is it not a time and concussion fuse that is desired? Fourth, is the fuse to be attached to the shell and fired ? Fifth, what kind of rifle shell is used ?—Is it on the button system, which allows windage and ignites the fuse without a fulminate, or is the sabot of such construction as to cut off all windage and thereby require a fulminate to light the fuze ? Any official facts pubhshed in your paper relating to the above would much oblige inventors in this country. Washington, D. C. Thomas Taylor. [We have not seen the notice referred to and cannot answer the inquiries made. Perhaps some of our correspondents may be able to give the desired information.—Eds.
This article was originally published with the title "Correspondence" in Scientific American 21, 10, 151 (September 1869)