M ‘ : Second Letier fant Dr. Hare to Prof Faraday. ; 
ee 
3 fy es (xxv,) you allege that conduction of heat differs i 
om. electrical induction, because it passes by a very slow pro- 
ss; ° while induction is in its distant influence simultaneous 
i ree at the place of action. How then can the passage a 
“of b % by conduction, be “a process precisely like that of radia- 
2 er (xxi,) which resembles induction in the velocity 3 with th whol @ 
uence - reaches objects, however remote ? 
A ough, Go a you appeal to the “ modern views s respect- 
in radia and cond ae of heat,’’ in order to ) illustrate your 
| oe the co hit of the particles of bodies subjected 
"<. to induction, yet in (xxv, oe object to th reference which I had _ 
| ae ade to these views, in r to shew that the intensity of elec- 
a “tropolarization could not be inversely as ‘the number of particles 
‘ ‘ erpose between the “inductric” surfaces. Let us then resort 
es ove suggested, “of the influence of the poles of a mag- — 
ee intervening pieces of iron wire. In 1679, 14th series, — 
: you sug ggest this as an analogous case to that of the process of _ 
ss ee ap electrical induction, which we have under consideration. 
auld there be in the one case a thousand pieces of wire inter- 
sed, in the second an hundred, will it be pretended that the in- 
raueuy of their reciprocal Soden’ reaction would be invers 
* as the number; so that the effect of the last mentioned num! ; 
of wires would be eqitivalent to that of the first?) Were inter- 
vals to be created between the wires by removing, from among 
a number first mentioned, alternate wires, it would seem to me 
that the diminution of effect would be commensurate not only — 
with the reduction of the number of the wires, but likewise with ‘ 
the consequent enlargement of the intervals. m ee 
:; . 
any excess of this principle with which a feeble affinity may have caused them to 
z be transiently united, or in receiving the rays emitted by any ee body, to a 
~ emanations from weliich they may have been exposed. 
“We may account, in like manner, for the great radiating power of earthen ware” ‘ 
and wood. * 
“ For th that calorifi b jected from the interior of a 
metal, they cannot enter it when projected against it from without. On the contra- 
ry, they are repelled with such on as to be reflected without any perceptible 
diminution of velocity. Hence t = slants of metallic reflectors. 
“It would seem as if the lone all which are condensed between those of 
= seu psepet any: — —, ose heir reere Heat may radiate towards 
nsue ; wise, on account of me- 
*ibeeal imperfpctions, easily discernible siale the aid a a microscope, mirrors 
would not be as efficacious as they are found to be in concentrating radiant heat. 
Their influence, in this respect, seems to result from the excellence of their 
eral contour, and is not poy impaired by blemishes.” 
¥ 
