70 YEAR-BOOK OP FACTS. 



minute, and the tang of the file was fixed in a chuck like a lathe 

 head, divided for the several cuts required in a complete revolution, 

 so that the whole process was carried out completely without any 

 difficulty. The Chairman (John Fenn, Esq.) observed that when 

 there was so great a difference as from 32d. to 4d. per dozen in the cost 

 of labour in the manufacture, the expense of the machine would be of 

 little consequence, since it would soon pay for itself if it did as good 

 work. Mr. B. Fothergill said he was acquainted with the working 

 of machine-cut files manufactured at Manchester, and they were 

 found to be quite as good and durable as the best hand-cut files, if 

 not superior ; he was satisfied that the best class of files would ulti- 

 mately be manufactured by machinery. 



See the details of the machine, with engravings, in the Mechanics' 

 Magazine, Feb. 17, 1360. 



price's patent improvements in locks. 



Mr. George Price, of Wolverhampton, has patented an invention 

 which consists of a novel and simplified arrangement and construe- 

 tionof certain parts of Locks, so as to prevent the possibility of picking 

 by what is known as the "tentative process," or feeling the position of 

 the gatings of the levers by applying pressure in any way to the bolt. 

 "Since the Great Exhibition of 1851," says Mr. Price, " it has been 

 universally admitted that the principle on which the picking of locks 

 depends is, that whenever pressure can be applied to the bolt in such 

 a manner as to indicate the points of resistance to its withdrawal, 

 such a look can be picked. Since this tentative method became 

 generally understood and practised in this country, many inventions 

 of a more or less complicated character have been patented to prevent 

 it ; but although most of them show that great ingenuity has been 

 employed in their construction, yet from their complex movements, 

 liability to derangement, unsuitableness for general purposes, and 

 their expensiveness, nearly all have been abandoned by the respective 

 patentees. The security against picking by pressure, obtained in 

 the construction of the locks above referred to, has been by the 

 addition of a number of ' limbs ' to the parts (the bolt, levers, and 

 springs) forming the essential mechanism of a lock, and which has 

 added, in corresponding proportion to the complexity, liability to 

 derangement, and cost. My improved lock comprises the dase, the 

 bolt, levers and Bprings of an ordinary lever lock, ami tin- security 

 against picking is mainly obtained by the peculiar arrangement anil 

 position of its parts." The peculiarity of the principle of its con- 

 struction is illustrated in the Michanics Mw/aziiir, June 15, I860. 



These Locks are not only warranted unpickahlc against every mode 

 of picking, but also proof against repeated charges of gunpowder, as 

 two ilwts. are said to be the most that can be hammered into it. "The 

 hardened steel nozzle," says Mr. Price, "preve n ts the keyhole being 

 enlarged, and the Bpindle of the knob being ease hardened, and 

 working in a rebate with a shoulder inside 1 , prevents gunpowder 

 being got into the lock-chamber by breaking the spindle." These 

 and other important improvements in locks and safes are secured by 



