Proceedings of Learned Societies. 99 
_ of air had been traversed. On the other hand, we have in the 
great daylight meteor of 1859 an example of the effects of the 
most extreme velocity—probably, between fifty ae : hundred 
miles per second. is body became visible at a probable 
height of near two hundred miles, and oxi: a brilliancy 
almost if not quite equal to that of the sun, being a conspicuous 
object to persons who were more than two undred miles from 
the nearest point in its path, i maintained its tomiacniey until 
within a few miles of the ea 
Philadelphia, May 23, 1863, 
Art. XIV.—Proceedings of Learned Societies.— Foreign. 
I, Royax Institution or Great Brirain.—Friday, Jan. 23, 1863. 
1. On Radiation through the Earth's Atmosphere ; ; by Jonn Tynpatt, 
Esq., F.R.S., Professor of "Nat. Phil., Roy. Inst.—-Nobody ever obtained 
the idea of a line from Euclid’s definition that it is length te breadth. 
process o stecmcaos more avs into accordance with the conditions 
of the atten So also with regard to physical phenomena; we must 
help ourselves to a conception of the invisible by means of proper images — 
derived aes the —. afterwards purifying our conceptions to the need- 
ful extent. Definiteness of co nceptions, even though at some eapenies to 
_ term radiation. It is well known that our edineent se is Palit com- 
posed of the two elements, oxygen and nitrogen. These elementary 
_ atoms may be figured as small spheres beaters thickly in the space 
: per acid, of amm onia, an and of s vapor. In these substances 
_ diverse atoms have coalesced to form li aod a of atonis. The mole- 
_ cule of aqueous vapor, for example, consists of two atoms of hydrogen 
_ United to one of oxygen; and they east as little triads ae the 
_ monads of oxygen and nitrogen, which constitute the great mass of the 
5 itiosephare 
_ These atoms and molecules are separate; but in what sense? They 
te from each other in the sense in which the individual fishes 
are separate. The shoal of fish is embraced by a common 
which connects the different ininbield of the shoal, and renders 
ell 
