ON THE MECHANICAL PROPERTIES OF STEEL. 161 



which is under ,£2,800,000, is about closed as far as new works are concerned, 

 while the revenue is rapidly increasing. For the half-year just ended, the 

 Company will be able to pay its preference and debenture stocks, 5 per cent, on 

 its floating liabilities, and about 2 per cent, on its ordinary stock of =£740,000. 



It will thus be seen that if the revenue increases in the same ratio that it 

 has hitherto done, viz. from ,£15,000 to ,£20,000 per annum, the Company will 

 be able to pay in two or three years a satisfactory dividend of 5 per cent. When 

 that event occm-s, the Directors may with propriety give some moderate aid 

 to the farther extension of the main lines of commmaication to Caithness and 

 Skye, both of which must prove valuable feeders to the Highland system. 



These lines were promoted chiefly by the great landed proprietors in the 

 country, among the most prominent of which were the Earl of Seafield, 

 Lord Fyfe, Mr. Matheson of Ardross, M.P., Mr. Meriy of BeUadrum, M.P., 

 Mr. M'Intosh of Raigmore, Col. Fraser Tytler, the Duke of Sutherland, &c. 



Experimental Researches on the Mechanical Properties of Steel. 

 By W. Fairbairn, LL.D., F.R.S., &^c. 



There is probably no description of material that has undergone greater 

 changes in its manufacture than iron ; and, judging from the attempts that 

 are now making, and have been made, to improve its quality and to enlarge 

 its sphere of application, we may reasonably conclude that it is destined to 

 attain still greater advances in its chemical and mechanical properties. The 

 earliest improvements in the process of the manufacture of iron may be 

 attributed to Cort, who introduced the process of boiling and puddling in the 

 reverberatory furnace, and those of more recent date to Eessemcr, who first 

 used a separate vessel for the reduction of the metals, and thus eflected 

 more important changes in the manufacture of iron and steel than had been 

 introduced at any former period in metallurgic history. To the latter system 

 we owe most of the improvements that have taken place ; for by the compara- 

 tively new and interesting process of burning out the carbon in a separate 

 vessel almost every description of steel and refined iron may be produced. 

 The same results may be obtained by the puddling furnace, — but not to the 

 same extent, since the artificial blast of the Bessemer principle acts with 

 much greater force in depriving the metal of its carbon, and in reducing it to 

 the state of refined iron. By this new process increased facilities are aftbrded 

 for attaining new combinations by the introduction of measured quantities 

 of carbon into the converting vessel, and this may be so regulated as to form 

 steel or iron of the homogeneous state, of any known quality. 



By the boiling and puddling processes, steel of similar combinations may 

 bo produced, but with less certainty as regards quality, as everything depends 

 on the skill of the operator in closing the furnace at the precise moment 

 of time. This precaution is necessary in order to retain the exact quantity 

 of carbon in the mass so as to produce by combination the requisite 

 quality of steel. It will be observed that in the Bessemer process this un- 

 certainty does not exist, as the whole of the carbon is volatilized or burnt 

 out in the first instance ; and by pouring into the vessel a certain quantity 

 of crude metal containing carbon, any percentage of that element may be 

 obtained in combination with the u-on, possessing qualities best adapted to 

 the varied forms of construction to which the metal may be applied. Thus 

 the Bessemer system is not only more perfect in itself, but admits of a greater 

 degree of certainty in the results than could possibly be attained from the 



1868. N 



