MECHANICS AND USEFUL ARTS. 31 



set them alight, sewing up, in cloths, fire, sulphur, and flax, which 

 they let down the walls by chains with the double purpose of blind- 

 ing and suffocating the assailants as well as destroying their engines. 

 When the walls were reached by means of mines, the besiegers 

 smeared the timbers with which they propped the walls during the 

 process of sapping with pitch and vast quantities of bacon fat. When 

 they had accomplished their task they retreated, setting fire to this 

 inflammable mixture. In fine, the energy with which the rude ma- 

 terials at command were used, and the invention bestowed upon 

 their application to destructive purposes, are lessons which the most 

 imposing of our guardsmen might study with profit. Water as well 

 as fire was largely taken into account as an assistant in defence. 



The immense number of castles, both in England and France, is 

 very remarkable. The French castles may be said to have accom- 

 modated the whole French army ; not so the English. The English 

 monarchs possessed an organized army of archers, which they could 

 command independently of any assistance from their nobles. This 

 is the reason why the French always lost and the English always 

 won. The French nobles feared to trust the lower classes with 

 weapons, feeling that their numerical strength was so considerable, 

 that, if once trained to act in combination, their own power would 

 be held in check. Their sovereign, therefore, relied entirely upon 

 them for his army, with the exception of hired troops of Genoese or 

 Braban9on archers. The nobles responded to his call with their re- 

 tainers, bidauds, valets, and brigands, forming a rabble rather than 

 a regular force ; and, as at the first reverse the hired archers took 

 the opportunity to plunder and return to their homes, these had to 

 bear the brunt of the battle. It is scarcely surprising? therefore, that 

 the chateaux were of an extent beyond that required for the vie 

 privee de la noblesse feodale. This extent begat immense power on 

 the part of the owners. 



-TESTING OF THE TUBES OF THE VICTORIA BRIDGE. 



Mr. Chas. Legge, C. E., of England, in a recent pamphlet entitled 

 A Glance at the Victoria Bridge, gives the following interesting ac- 

 count of the manner in which the great tubes were tested, and of his 

 personal experience in connection with the experiment : 



On the 15th of December, preparations were completed for a final 

 test of the strength of the tubes ; singularly enough at the same time 

 with the close of navigation, when vast fields of ice, under nature's 

 superintendence, were hurling their solid masses against the masonry 

 of the piers and testing their efficiency and strength by over one mil- 

 lion tons a minute. Any force or weight man could bring into com- 

 parison with this would be puny in the extreme. Yet, notwithstand- 

 ing the inability of competing with nature's test, a load had been ob- 

 tained such as seldom before was seen for a like purpose. A train of 

 platform cars five hundred and twenty feet in length, extending over 

 two tubes, was loaded, almost to the breaking limit of the cars, with 

 large blocks of stone, and in readiness for the experiment. Prior to 

 this a steel wire was extended the entire length of the tubes for the 

 purpose of measuring the deflection, and strained by heavy weights 



