American Journal of Science. 7 
Philosophical Instruments, Manufactured and Sold 
BY N.B. & D. CHAMBERLAIN, 
Nos. 2 ann 9 Scnoor Srreet, Boston. 
Attwood’s Machines, with Seoul Clocks, Weights, &c. com- 
plete, eight feet high, $25 , $50, and $100. Tables with Spring 
Pistols, &c. for Compound Bégien and Forces, B6. Whirling Ta-| 
es and Fixtures, complete for a variety of experiments, $25 aval 
$35. Mechanical Powers, in complete sets, $25, $40, and $100. 
Hydrostatic Presses, Hydrostatic Bellows, Hydrostatic Paradox, 
Glass Barrel Lifting Eaton and Improved Forcing Pump, and) 
Stand, with Cisterns, Hose, &c. 
Air Pumps, all worked with the Simple Lever. 
No. 1, eight inch plate, barrel 7 by 21 inches, $25. No. 2, 
eight inch plate, two barrels 7 by 2! inches, $35. No. 3, twelve! 
inch plate, barrel 11 by 34 inches, has a barometer gauge, $75.. 
No. 4,* thirteen inch plate, barrel 13 by 4 oP ey $125. No. 5, 
fifteen inch plate, barrel 13 by 44 inches, $150 
ell Glasses are fitted to all the different parnps, from half re 
to fourteen gallons. Prices from 25 cts. to $12. 
Electric Machines.—Sixteen inch plates with two conductors, 
well proportioned and finished, $25. ‘Twenty four inch plate, with 
two edie 2% $40. Twenty eight inch plate, two conductors, 
o $60. Thirty inch plate, two conductors, $75. Thirty 
cae plate, two conductors, $85. Forty inch plate, two con- 
cioga $125 to $150. Fifty five inch plate, two negative con- 
ductors, two vice rubbers, prime conductor 7 feet by 8 inches, 
$400. All the usual varieties of apparatus accompanying the above 
machines, at fair prices. 
Chemicals.—Cylindrical Gasometers, with Webster’s Improved 
Compound a Cisterns with Gas Holders, Retorts for Oxy- 
gen, Lamp Sta , Gas Bags, Pyrometers, &c., Chemical sien 
all sizes and ee 
Galvanic and Electro-Magnetic Apparatus. 
Working Models of Steam Engines,. $35, $60, to $100. Sec- 
tion Models of Steam Engines, $12 to #18. 
Astronomicals. —Orreries, Season Machines, Tide Dials, Globes. 
For further and more particular information, see Catalogues, 
which will be lormened on application. 
oston, March 11, 
| 
b 
t . epee, one by Prof dimsted. Yale Colton, one b by 
Prof. Young. otk College, one by Prof. Hopkins, Williams College, one oe 
Prof. Whipple, Oberlin Collegiate Haniel raha al of No. 3, and some t 
how in use in aciakeinbes in the United 8 
