416 NEGRETTI AND ZAMBRA, HOLBORN VIADUCT, E.G., 



ft 



\ A 



FIG. 2397. FIGS. 2400, 2400*. 



FIG. 2398. 



x\ 



FIG. 2401. 



Each. 



FIG. 4201*. 



Each. 



2397 Jointed Dischargers, with glass handles, for discharging 



electrical jars, batteries, &c. (fig. 2397) . 8s. 6d. 11 



2398 Ditto ditto French pattern, with two glass handles 



(fig. 2398) 15 



2399 Small Discharging Rods, not jointed . . . .03 



2400 Medical Electrical Directors, with glass handles, for 



pa.ssing a shock through any part of the body 



(figs. 2400 and 2400*) 3s. 6d. 5 6 076 



2401 Electrical Directors, for the Eye and Ear (figs. 2401 



and 2401*) 10 6 12 6 



2402 Two Jars, mounted, for explaining the Franklinian 



theory (fig. 2402) 14 



2403 Ditto ditto, with Insulated Stand, ball and wire (fig. 2403) 140 



2404 Biot's Apparatus, for illustrating the distribution of electricity on the surface 



of insulated conducting bodies, It consists of a sphere of copper, supported 

 on an insulating glass rod and stand, and two thin copper hemispheres of 

 such a size as to enclose the sphere. The covers are fitted with glass 

 handles, so that they can be removed from or placed over the sphere, 

 without the hands touching the metal ^fig. 2404) . . 2 15 



FIG. 2395. 



FIG. 2405. 



FIG. 2404 



