424 Machinery at the Exhibition. 



way of machinery must remain to be discovered. But there 

 is, and there always will be, abundant opportunities for making 

 valuable improvements in practical science, and the time that 

 has elapsed since 1851 has been by no means barren in such 

 indications of progress. This will be sufficiently evident to 

 those who compare the past with the present Exhibition. 

 Eleven years constitute a very considerable portion of the dura- 

 tion of human life; those who eleven years ago were young 

 are now of mature age ; and those who were then of mature 

 age are now old; but we and numbers of our readers can 

 make the comparison. In doing this, it is impossible not to 

 advert to the very important part which is played by those 

 contrivances which are included under the general name of 

 'machine-tools. In reality they are the means by which all im- 

 provements are effected in the construction of the various kinds 

 of machinery ; and thus, indirectly, they are the sources of 

 every advance in arts and manufactures. The imperfections 

 of these appliances, or, as we ought rather say, the want of 

 them, caused the greatest difficulties and embarrassments to 

 Watt in his endeavours to improve the steam-engine. But 

 time removed these obstacles to the carrying out of his admi- 

 rable conceptions. This, however, was merely in accordance 

 with a general law, by force of which the creation of a demand 

 is always followed by a means of supply. Thus the necessity 

 of forging an unusually large bar led Nasmyth to the invention 

 of his steam-hammer. The impossibility of guiding a turning- 

 tool with accuracy, or indeed at all, without almost intolerable 

 labour, in the case of very heavy work, led to the invention of 

 the slide-rest. The nearly incontrollable vibration of a long 

 bar, in a single lathe, led Whitworth to the invention of his 

 duplex : and such instances might be multiplied almost without 

 limit. 



Comparing the machine-tools exhibited in 1851 and 1862, 

 we find that the lathe, planing, slotting, and drilling-machines, 

 exhibited on the last, might very well take their places on the 

 present occasion, so little have they been altered. The lathe is 

 by far the oldest contrivance, and it is still the most generally used 

 in the construction of machinery. In its best form, it may be 

 considered as a kind of universal appliance, that to a great ex- 

 tent may be made to supply the place of every other ; for besides 

 turning, it will bore, and drill, and even plane, etc. As might 

 be expected from its importance, it was not only well repre- 

 sented at the last Exhibition, but on a very large scale also ; 

 since, among the specimens of it were some for turning rail- 

 way-wheels seven feet in diameter, and shafting thirty-six feet 

 in length, and we have scarcely advanced farther since that 

 time. The enormous weight of those lathes which are used for 



