130 



LITHOGRAPHIC PRESS 



Brought forward 

 Magnesium chloride 

 Aluminum chloride . 

 Potassium chloride . 

 Sodium chloride 

 Lithium chloride 

 Potassium bromide . . . 

 Potassium silicate . . 

 Nitric acid .... 

 Ammonia 



Grains per gallon 



485-06 



11-80 



63-09 



6-30 



. 407-47 



3374 



trace 



5-03 



. trace 

 trace 



Total 1012-49 



XiXTHXTTM is the metallic basis of lithia ; the latter substance consists of 100 of 

 metal and 123 of oxygen. Lithium is the lightest known solid, its specific gravity 

 being 0'59. Its atomic weight (7) is lower than that of any other element, excepting 

 hydrogen. Lithium is not of any use in the arts. See LITHIA. 

 XiITHOFR.&.CTnra. See EXPLOSIVE AGE>TS. 



XtXTHOCZ&AFKXC PRESS. The lithographic press in common use has long 

 been regarded as a very inadequate machine. The amount of manual power required 

 to work it, and the slow speed at which, under the most favourable circumstances, 

 copies can be produced, disables lithography in its competition with letter-press. A 

 career of brilliant success has attended the efforts of scientific men towards speed and 



success in this latter branch of 



1395 the art ; and the present printing- 



machines surpass the hand-press 

 somewhat in the same ratio as 

 does our express-speed the jog- 

 trot of our forefathers. The 

 engravings annexed, Jigs. 1395, 

 1396, will serve to illustrate 

 Messrs. Napier and Sons' im- 

 provements upon the lithographic 

 press. The machine is arranged 

 to be driven by steam-power ; lias 

 belts, 'crossed 'and 'open,' sup- 

 posed to be in connection with 

 the engine, and to rank upon the 

 pulleys, A, B, c. The crank- 

 pulley, B, is fixed on the screw- 

 spindle, D, and the other two work 

 loose, or 'dead,' on the same 

 spindle ; these bands, with their striking-forks, a, are arranged so as to be brought 

 alternately upon the fixed pulley, B, and thus a reversing-motion is given to the 



1396 



screw. The nut in which the screw works is fixed to a cross-piece, E, which braces 

 the side-frames, F F, together at bottom, while the bar, o, performs the same office at 

 top ; the scraper-box, H, is sustained between these frames at bearings, i, and is so 

 fitted as to work freely. To support the frames and scraper-box independent of the 

 screw and maintain them in position, allowing freedom of action, the rollers, J J, 

 are provided, which run in the planed recesses, K, along the top of the main stan- 

 dards, i.. 



