130 ANNUAL OF SCIENTIFIC DISCO VEEY. 



when a person absent from home may be expected to return, which is very 

 convenient for medical men. It consists of a small plate of metal, on the 

 back of which two discs are made to revolve. On the circumference of one 

 disc are printed the hours in Eoman numerals, the other contains the minutes 

 in Arabic characters. By turning the discs every hour and minute may be 

 shown, by bringing them opposite two apertures in the metal plate. 



Machine to record the Beatings of the Pulse. In a machine for the above 

 purpose, invented by Professor Bierordt, Frankfort, Germany, the arm of the 

 patient is placed in a longitudinal cradle, and screwed down sufficiently to 

 keep it steady. A small erection on one side holds a sort of lever worked on 

 a hinge, at the end of which a pencil is inserted, the point of which has been 

 dipped in Indian ink. This goes into a cylinder upon which paper has been 

 stretched. The lever rests upon the pulse, and at every moment records the 

 action upon the paper. If the pulse is steady a regular, zig-zag line is drawn 

 on the paper, but in cases wkere the pulse is rapid and jerking, the line goes 

 up and down, making long and uneven marks. 



Japanning Leather. A. V. Newton, of London, has secured a patent for 

 opening the pores of leather, by impregnating it with sulphur, for the purpose 

 of preparing it for enduring a great degree of heat, and for toughening its 

 fibers. The sulphur is combined with varnish, and any gum-elastic solution 

 may also be combined with it. 



Bearings for loose Pulleys. The object of this invention of Messrs. Campbell 

 & Shippeu, patented October, 1854, is the placing of a loose pulley and hanger 

 beside a driving pulley on a hue-shaft, or on any intermediate shaft bearing 

 the same relation to a lathe or other machine, to be detached as a line-shaft, 

 whereby is obviated the continual wear attendant upon the loose pulley, shaft- 

 ing, and belts, when a lathe, or loom, or other machine, driven in from the 

 line of shafting is not running. The loose pulley and hanger having an axis, 

 may be made to revolve independent of the shaft. The improvement obvi- 

 ates the necessity of throwing belts off the pulley in order to prevent the 

 wear of machinery while the engine is in motion, also making it more safe 

 for the operatives. 



Machine for Trimming Books. Few substances are more difficult to cut, 

 with a smooth, true edge, than sheets of paper laid together in quantities. 

 Printers and bookbinders have always experienced the truth of the fact, al- 

 though many an inventor has studied hard to relieve their troubles from this 

 cause. Complete success, however, has never been reached. Many ingen- 

 ious devices have been made, but nearly all of them fall short of the mark, in 

 one way or another. Mr. Blehl, of Cincinnati, claims for an invention recently 

 patented a superiority over all others. The sheets of paper to be severed are 

 laid on a table, the knife is attached to a crank arrangement and pitman, in 

 such a manner that by turning the crank the knife-edge is forcibly drawn 

 across the paper and the cutting thus effected. This drawing movement of the 

 knife is the peculiar feature. 



Improvement in Screw-Fastenings. This invention of London & Ahlstrom, 

 of New York City, relates to expanding screw-fastenings, to be used under 

 conditions in which bolts and nuts of the common construction are not appli- 



