CHEMICAL SCIENCE. 201 



irons, to the extent of from one quarter per cent to about one or one and a 

 half per cent, is mainly due the rise, progress, and present prosperity of 

 Sheffield and its manufacturers. 



When pure gray cast iron is alloyed with titanium in certain proportions, 

 it may, when cast into ingots, be drawn into bars of great strength and tena- 

 city. I havejthus drawn an ingot of gray cast iron three inches square into 

 bars three-quarters inch square, and perfectly sound. 



The specific gravity of titanium has been most erroneously assigned by 

 chemists as 5.3. It is in reality a metal somewhat heavier than iron, and that 

 steel which contains a large alloy of titanium is consequently found to have 

 a higher specific gravity than other steel. It may be objected that small 

 proportions of titanium, in alloy with iron, cannot produce a marked effect. 

 To this I reply, that with one-half per cent of carbon, and under that propor- 

 tion, are produced nearly all the marketable varieties of bar iron and steel 

 with which we are familiar; and it is also certain that one-half per cent of 

 phosphorus renders bar iron crystalline, and one-half per cent of sulphur 

 occasions redshortness; therefore, that so small a quantity as one-half per 

 cent of titanium should constitute the excellence of steel iron is not at all 

 an anomaly. Magnetic iron ores always contain some titanic acid, and 

 such is its efficacy in improving the quality of iron, that the most impure 

 magnetic ores, abounding with pyrites, nevertheless yield iron of a superior 

 class. If the iron used in the manufacture of rails was prepared from pig- 

 iron, smelted from ordinary iron ores, with the addition of a tenth part of 

 titanium, or even one-twentieth, the rails thus manufactured would be at the 

 least four times more durable than they are found to be under the present 

 process of manufacture. This is only one of the many important results 

 which the discovery of the effects of an alloy of titanium upon iron will 

 lead to. The deposit of titanium ore of the iserine variety, to which I 

 have alluded, extends twenty miles in length by half a mile in breadth, and 

 lias no bottom at four yards in depth. It is all of one uniform quality, in 

 the state of iron-sand, so minutely divided, that of half a ton which I have 

 had, the Avhole of it readily passes through the meshes of a sieve of three 

 thousand six hundred holes to the square inch, that is to say, the largest 

 grains are not so much as one thirty -six hundredth part of an inch in dia- 

 meter. From my experiments with iserine heated and immersed in water, I 

 am of opinion that the whole of this extraordinary deposit of iron-sand has 

 been, when at an intense temperature, suddenly quenched in water. It pro- 

 bably existed in the interior of a volcano, into which at some epoch an irrup- 

 tion of the sea has taken place, and the sand has been thrown out by the 

 force of the explosion which must have ensued. The region is volcanic, and 

 there are lofty extinct volcanoes near the locality of the deposit. 



Reckoning thirty hundredweight per cubic yard as the weight of this sand, 

 the number of tons in the area already ascertained of this deposit will amount 

 to one hundred and eighty-five millions eight hundred and fifty-six thousand 

 tons, a quantity sufficient to furnish a supply for all the furnaces in England 

 with ore for twenty-five years. 



IMPROVEMENTS IN THE MANUFACTURE OF IRON. 



It is well known that articles of cast* iron may be rendered malleable in a 

 do rree, by closely packing them in powdered hematite (peroxide of iron) in 

 tight fire-brick cases, and subjecting them to a red heat, in an annealing 



