MECHANICS AND USEFUL ARTS. 69 



next demonstrated the non-perfect security of the no less distinguished 

 Chubb form of lock, in which great ingenuity is displayed in the com- 

 bination of what are called -'tumblers;" and concluded by suggesting 

 that the true mode of construction consisted not in multiplying diffi- 

 culties which, with patience, might be overcome, but by the applica- 

 tion of new principles ; and he shortly pointed out the advantages 

 resulting in this respect from the elaborate performance, for which 

 his peculiar genius must be held in high respect. 



An interesting discussion followed, in which Professor Cowper, Mr. 

 Gregory, Mr. Hodge, and others, took part. The result of which 

 seemed to indicate, that as long as it required so much time and so 

 great ingenuity, in a practised hand, to pick locks, and as long as it 

 would be necessary to give 40 or 50 to become the owner of one 

 of Mr. Hobbs' unpickable locks, the locks of Bramah and Chubb the 

 best of which, for ordinary purposes, might be obtained for less than 

 3 would lose nothing of their true value for the common purposes 

 to which they are applied. 



NEW MILITARY TACTICS. 



SIR CHARLES SHAW, in a recent letter to a London Journal, on 

 the changes necessarily made in military tactics consequent on the 

 introduction of new and improved weapons into the service, states, 

 that the improved musket-rifle can render cavalry and artillery use- 

 less at nine hundred yards distance, and the nail ball, out of the old 

 musket, can do the same (as I have witnessed,) at a distance of six 

 hundred and fifty yards. But suppose I am said to be mistaken as to 

 cavalry and artillery ; I believe at this moment there is not a regi- 

 ment of cavalry that could be brought to make an effective charge 

 against a well served field-battery, owing to the confusion and fear of 

 the horses at the noise and smoke of the cannon. To remedy this, 

 and give the horses confidence, the Russians, in the wars of the 

 Caucasus, in drilling, had batteries before the watering places of the 

 cavalry. The cavalry got no water the morning of the drill, but 

 after some hours of hard work, the horses became thirsty. The cav- 

 alry were posted in front of the field batteries, which began to play. 

 Loose reins were given, and, at full gallop, the cavalry passed between 

 the guns of the batteries, and thus lost fear of artillery. 



IMPROVEMENTS IX LIFE-BOATS. 



WITHIN a comparatively recent period, a circular was issued by 

 the Duke of Northumberland, England, offering a premium of 100 

 guineas for the best model of a life-boat, and pointing out, as the 

 three principal defects of existing life-boats, the want of self-righting 

 power, inability to free themselves from water, and a heaviness which 

 prevented their being transported along the beach. In consequence 

 of this offer, no less than 280 models and plans were submitted, by 

 different inventors throughout Great Britain. In addition to the 



