12 BRNJ. PIKE'S, JR., PRICE CATALOGUE. 



No. 



246 Figs. 154, 155, 156, and 158, set of mechanic 



powers, with graduated framework, four 

 systems of pulleys, wheel and axle, levers 

 of first, -second and third order bent lever, 

 screw with lever, inclined plane with gradu- 

 ated arch, carriage wedge in two parts, 

 and a set of brass weights, - $16.00 



247 Fig. 159, 160, 161, 162, and 163, improved 



and elegant set of mechanic powers, con- 

 sisting of a complete set, with an apparatus 

 for the composition and resolution of forces. 

 The whole mounted on four polished maho- 

 gany frames, uniform in their size and finish, 60.00 



248 Fig. 164, screw press, - - 2.25 



249 Fig. 165, endless screw, - - $6 and 8.00 



250 Fig. 166, capstan, - - 2.50 



251 Fig. 167, double cone, - $1.50 and 2.00 



252 Fig. 167, double cone with adjusting screws, 3.00 



253 Fig. 168 to Fig. 174, whirling table, for ex- 



plaining and demonstrating the laws of the 

 planetary motions, and other properties of 

 gravity and centrifugal forces, - - 75.00 



254 Fig. 175, whirling table of simpler construc- 

 tion, with the apparatus represented in 

 Figs. 169, 170, 171, 172, 173, and 174. 30.00 



255 Fig. 176, Atwood's elegant and accurate ap- 



paratus for demonstrating the laws of acce- 

 lerated and retarded motion, and other in- 

 teresting laws in mechanics, with clock 

 beating seconds, ----- 100.00 



256 working model of steam engine, - $35.00 to 90.00 



PNEUMATICS. 



AIR PUMPS AND APPARATUS. 



257 Fig. 177, improved lever air pump, with 

 mercury gauge and polished mahogany 

 frame, - 70.00 



