MAGNETIC INSTRUMENTS. 27 

 No. 



604 Fig. 428, helix on stand, - - $2.50 and $3.00 



605 Fig. 429, circular magnetic coil, - 2.00 



606 Fig, 430, apparatus for Oersted's experiment 3.00 



607 Fig. 431, apparatus for Oersted's experiment 



with graduated circle, - - -, 3.50 



608 Fig. 432, galvanometer, or galvanic multiplier, 3.50 



609 Fig. 433, galvanometer needle suspended by 



a silk thread, - - 8.00 



610 Fig. 434, galvanometer, with astatic needle, 7.00 



611 Fig. 435, improved galvanometer, with ditto, 15.00 



612 Fig. 436, gold-leaf galvanoscope,with magnet, 5.00 



613 Fig. 437, Barlow's electro-magnetic globe, - 3.00 



614 Fig. 438, March's vibrating wire, 2.00 



615 Fig. 439, Barlow's spur-wheel, - $2.50 to 3.50 



616 Fig. 440, ditto, two wheels, $4 to 5.50 



617 Fig. 441, wire revolving round a magnet, - 3.50 



618 Fig. 442, revolving magnet, - 5.00 



619 Fig. 443, vibrating magic circle, - 6.00 



620 Fig. 444, electro-magnet, with three poles, - 3.00 



621 Fig. 445, magnet revolving round a wire, - 9.00 



622 Fig. 446, Ampere's rotating battery, 6.00 



623 Fig. 447, revolving cylinders, - 8.00 



624 Fig. 448, Page's revolving armature, - - 4.00 



625 Fig. 449, revolving wheel and armatures, $6 and 7.00 



626 Fig. 460, Page's revolving magnet, - $6 and 7.00 



627 Fig. 451, Page's revolving magnet, with elec- 



tro-magnet, - 7.00 



628 Fig. 452, magnetic beam engine, . * * 12.00 



629 Fig. 453, beam engine with curved armatures, 18.00 



630 Fig. 454, magnetic engine, - 15.00 



631 Fig. 455, bell engine, - - 12.00 



632 Fig. 456, horizontal bell engine, - - 20.0C 



633 Fig. 457, movable wires for showing attrac- 



tion and repulsion, 5.50 



634 Fig. 458, scintillating circle, 8.00 



635 Fig. 459, Lockey's coil machine with scintil- 



lating circle, - - 12.00 



636 Fig. 460, apparatus for detonating gases by 



magneto-electric spark, - - - 25.00 



637 Fig. 461, Bird's inverser, - 5.00 



638 Fig. 462, water regulator for modifying gal- 



vanic shocks, - .... 4.00 



