i54 



HA RD WI CKE 'S S CIENCE- G O SSI P. 



dozia reptans, L. ; L. stfacca, Mitten. Bazzania 

 trilobata, L. ; B. tricrenata, Lindley ; B. triangu- 

 laris, Schl. Odontoschisma Sphagni, Dicks. Ccpha- 

 lozia bicuspidata, Dum. ; C. Lammcrsiana, Hiibn. 

 Lophocolea bidcntata, L. ; L. hetcrophylla, Schrad. 

 Chiloscyphus polyanthos, L. Saccogyna viticulosa, 

 Mich. Kanlia Trichomanis, L. TricJwcolea tonien- 

 tclla, Ehrh. Blepharozia ciliaris, Nees. Herbcrta ad- 

 ufica, Dicks. Anthelia julacea,', Lightf. ; A. Ju?-atz- 

 kana. Blcpharostoma trichcphyllum, L. Scapatiia 

 undulata, Dill. ; S. nemorosa, L. ; .S. resupinata, 

 Dumort ; S. purpurea, Carr ; .S". planifolia, Hook. 

 Diplophyllum albicans, L. riagiochila asplenioides, 

 L. ; P. spinulosa, Dicks. Mylia Taylori, Hook. 

 Eucalyx hyalina, Lyell. Jungermannia crenulata, 

 Sm., and var. gracillima, Sm. ; J. lurida, Dum. ; 

 y. sphccrocarpa, Hook. ; y. cordifolia, Hook. ; y. 

 riparia, Tayl. ; y. Mulleri, Nees ; y. barbata, Schreb. 

 y. Flxrkii, Web. et Mohr ; y. quinquedentata, 

 Web. ; J. lycopodioides, Wallr. ; y. ventricosa, Dicks. ; 

 J. incisa, Schrad. ; y. minuta, Crantz. Nardia emar- 

 ginata, Ehrh. ; N. compressa, Gray ; N. scalaris, 

 Schrad. Gymnomitrium concinnatum, Corder ; G. 

 crassifolium, Carr ; G. crenulatum, Gottsche. Blasia 

 pusilla, L. ; Pellia epiphylla, L. ; P. calycina, Tayl. 

 Aneura pinguis, L. ; A. sinuata, Dicks. ; A. multi- 

 fida, Dill. Metzgeria furcata, Dum. ; M. pubescens, 

 Schrank. ; M. conjugata, Lindley. 



P. Ewing. 

 Glasgow. 



THE SUN : ITS WASTE OF HEAT, &c. 



MUCH speculation has been before the public 

 for some time on this subject. On our little 

 earth scientific men have for years told us that 

 plants and trees, men and animals, decay and die, 

 and are resolved into their respective elements to 

 form new combinations and be utilised, and that 

 nothing is lost ; why, then, should the sun have 

 loss ? I give you the theory of an acute mind and 

 good practical astronomer, Mr. Nasmyth, a first-rate 

 engineer, as all know. His opinion is this, "Solar 

 light, its main source appears to result from an 

 action induced on the exterior surface of the solar 

 sphere, a conclusion with which all observers of its 

 surface will agree. I was led to consider whether 

 we might not reasonably consider the true source of 

 the latent element of light, to reside, not in the solar 

 orb, but in space itself ; and that the grand function 

 and duty of the sun was to act as an agent for bring- 

 ing forth into vivid existence its due portion of the 

 illuminating or luciferous element, which element I 

 suppose to be diffused through the boundless regions 

 of space, and which in that case must be perfectly 

 exhaustless," vide "Life of Nasmyth," by Smiles, 

 P- 355. These words coming from such a man are well 



1 worthy of our most serious consideration. Allow me 

 to suggest a theory of my own, recorded in my note- 

 book long before I saw Nasmyth's autobiography. 

 I know very well I shall have an army of spectroscope 

 men down upon me at once. But let them tell us how 

 many of their spectrum lines are due to our atmos- 

 phere. Of course we must all bow down to the un- 

 dulatory theory of light — though some things in my 

 experience of 45 years seem to militate against it. 

 Taken broadly, the theory is a sound one. Now, 

 whether the sun propagates waves of light, heat, and 

 actinism all round into space, or, as Mr. Nasmyth 

 suggests, inaugurates mesial vibrations in a medium of 

 extreme tenuity, matters little to my theory. I main- 

 tain that however these waves are set in motion, they 

 contain within themselves only latent heat, light, and 

 actinism. For where a force is not energised it can 

 hardly be said to exist except potentially. On meet- 

 ing with a resistant body like our earth, the planets, 

 or the moon, whether the soft cushion of an atmosphere, 

 or the barren reefs and gigantic eminences of our satel- 

 lite ; then thrown into abnormal vibrations (a cross sea), 

 these waves break into heat and light. Is there any 

 heat or light from the sun outside these conditions ? 

 Ascend with Glaisher and a companion seven and a half 

 miles above the earth's surface, and the cold is so intense 

 that, but for the warm blood of a young man, the whole 

 party would have perished. Imagine if you can, the 

 cold 5,000 miles from our standpoint, and I fancy 

 the polar regions would be genial compared with it. 

 Light — if the sun is constantly wasting this on all 

 sides in space — how comes it, that on a clear star- 

 light night we have so little light ; or rather, mutatis 

 mutandis, why should we see the stars any plainer than 

 at noonday in the Tropics ? I will say nothing about 

 refraction, which ought to give us more light at 

 night, nor of the earth's shadow in space, of which 

 I am quite aware. Take the following as illustrations 

 of my meaning. The sun has been taking pictures 

 for countless ages, but it requires the chemist's art 

 and manual dexterity to develope a perfect photo- 

 graph. I heave (I prefer the dear old Devon 

 " Hevive " though no writing can express the softness 

 of the u and v) a huge stone into a small pond. From 

 the centre of depression, rings of tiny waves are 

 propagated and reach the margin — still I am not 

 aware that a drop of water is lost or wasted. . . . 

 Watch a heavy ground swell coming in from the 

 Atlantic. Not a cloud in the summer sky, not a 

 breath of air — on they come, without a speck of 

 foam or a break, massive, silent in their majesty — a 

 cable's length from crest to crest. But let them 

 meet a rocky islet, or an ironbound coast, and the 

 passive becomes active — leaping up in wild horse's 

 manes, and falling back in cataracts of foam, or in 

 thunder searching out the recesses of each rock cave, 

 shaking the earth around, and filling the mind with 

 awe, and the potential becomes the actual. 



A. H. Birkett. 



