Proceedings of the Polytechnic Association. 735 



if obtained from tlie dead, it is probably removed when putrefaction 

 has set in. 



MouNTAi2f Locomotion. 

 Charles De Bergue proposes to give the locomotive -n'orking np 

 steep grades a new climbing power by a novel arrangement, to which, 

 however, serions objection may be made. The engine, tender and 

 cars are all coupled together by a single link, witliout the intervention 

 of springs or buffers, so that each truck or carriage sustained by four 

 wheels, will be maintained at a fixed distance from the locomotive. 

 The two wheels on each side of the truck or carriage are coupled 

 together in the usual manner and driven by rocking shafts and a 

 continuous pair of connecting rods in direct communication Avith the 

 engine. On curves it is apparent that while the center line of the 

 train remains unchanged in length, the connection on one side must 

 be elongated, and on the other shortened. Mr. De Bergue believes 

 that with a stroke of two feet this difference %vill not be more than 

 one forty-fifth of an inch, which may be made up by slacking the 

 bearings. This invention does not successfully meet the difticulty, 

 and the problem of connecting the motor with each segment of a 

 train remains, as yet, unsolved. 



Testestg tue Weight, of Coin. 

 From an article on " Coin and Coining," by Joseph TSTewton, of the 

 Royal Mint, London, we gather the following interesting information : 

 The automatic weighing machine was introduced at the Royal Mint 

 by Capt. Harness. To Mr. James M. Napier, the celebrated engineer, 

 of York road, Lambeth, however, must be awarded some of the credit 

 of perfecting the mechanical arrangement of the apparatus. The 

 Bank of England had previously adopted an automatic system for the 

 detection and rejection of light sovereigns and half-sovereigns, and this 

 circumstance, no doubt, led to the introduction of a similar plan at the 

 mint. The bank machines took no cognizance of too heavy coins ; their 

 objection only extended to those which were too light. It will be readily 

 understood that if the mint authorities allowed coins to escape which 

 were above the legal maximum weight it would tell seriously upon 

 the expenditure. If, on the contrary, they jjerniitted light pieces to 

 go into the hands of the public, the latter would be defrauded. These 

 exigencies demanded more complexity than was required by the bank 

 automatic mafehines. The mechanical problem involved in the mint 

 requu-ements was solved by Mr. Napier, and his machine was found to 



