222 ANNUAL OF SCIENTIFIC DISCOVERY. 



quantity of sandstone should be regulated so that the silica and alumina in 

 the charge may hear to each other the same, or nearly the same, proportion, 

 as was the case with the Cleveland iron-stone, which Avas as follows : Cal- 

 cined iron-stone, 11 cwt.; sandstone containing ninety-three per cent, of 

 silica, 1 cwt.; limestone, contaning fifty-three per cent, of silica, 4 cwt. 

 This invention consists in adjusting the proportion of the silica and alumina 

 in the charge by the addition of silica, where ores are employed which do 

 not contain such a quantity of silica (when combined with lime to form a 

 slag) as will carry down the alumina which the ore contains, and at the 

 same time produce a sufficiently fluid slag. In this manner Mr. Morgan is 

 enabled to smelt ores of this description as advantageously as ores which 

 naturally contain silica and alumina in such proportions as to produce fluid 

 or fusible slag. It will be seen that the principal feature in this method con- 

 sists in employing silica as a flux. Now, as has been remarked, the use of 

 silica is as well known, or ought to be, by all who have charge of furnaces, as 

 limestone, and consequently the mere employment of that substance for that 

 purpose would not prevent its use by others either in the form of sandstone 

 or sand; but we are told by Mr. Morgan that he is aware that silica has been 

 used before as a flux ; but heretofore it has been used with ores which do 

 contain sufficient silica to carry down the alumina, that is to say, at least 

 two of silica to one of alumina, but which, nevertheless, do not contain 

 silica enough to make sufficient slag to protect the iron from the blast, and 

 for the proper working of the furnace. This inventor claims only the em- 

 ployment of silica, where it is used together with ores, in which the quantity 

 of alumina present is equal to or exceeds one-half of the quantity of silica. 

 New Yoj'k Tribune. 



Carmont and Cobett's Improved Furnace. In this invention, the flues of 

 furnaces for the production of wrought iron or steel are so constructed as to 

 rise perpendicularly from the grate, so as to carry off all deleterious gases 

 generated in the process of manufacture, and also in preventing such delete- 

 rious gases coming in contact or being incorporated with the metal so man- 

 ufactured. Furnaces thus constructed cause the heat powerfully to reflect 

 and reverberate upon the me.tals, and at the same time prevent all flame or 

 smoke passing over or coming into contact with the metal while in a state 

 of fusion. New York Tribune. 



Improvement in the Manufacture of Cast Steel. In a communication to the 

 London Engineer, Mr. Robert Mushet, in commenting upon the " Bessemer 

 process" for manufacturing iron, describes improvements which he has 

 made in producing steel from cast iron. In an experiment with "Welsh No. 

 1 pig iron, which was purified in a Bessemer furnace, he added ten pounds 

 of a triple compound of malleable iron, carbon, and manganese, to every 

 seventy-two pounds of the cast iron, and the ingots made from this were 

 good welding cast steel ; on the other hand, ingots made from the same pig 

 metal without the manganese and carbon being added, were so brittle that 

 they cracked to pieces, at both a high and low heat, when worked under the 

 hammer. He asserts that there never was, or can be, a bar of first-rate 

 cast steel made by the Bessemer process alone. It is generally held that 

 molten iron cannot contain oxide of iron in solution, but Mr. Mushet is of a 

 different opinion. He also asserts that a very small quantity of metallic 

 manganese, introduced among molten cast iron, counteracts all the perni- 

 cious effects of phosphorus and sulphur in it. He says : " I have merely 

 availed myself of a great metallurgical fact, namely, that the presence of 



