250 



. KNOWLEDGS 



[Sbpt. 8, 1882. 



thp «ik. and is grwn. with two white h'ncs down the back, and an 

 oblique red stri|>e, edgvd with yellow on the side of each scgnitiu. 

 It shoald be sought for from July to September. 



In the fore£f<iing notes we have endeavouretl to jmint out tin' 

 principal characteristii-s of eneh siwcios of this iuterestinfr fumily 

 of moths, B9 few entomologists appear to have taken as nuuli 

 notice of them as their beautiful structure deserves, and we should 

 advise all collectors to more thoroughly examine tree-trunks and 

 under fallen leaves during this and the next month, as many of the 

 rarer Prominents might become more known by these meaus. 



(Pur IJnratior Coinrr. 



PROFESSOR SCUWEDOFF'S THEORY OF HAIL. 



THE British Association supplies this year, and not for the first 

 time, a full-gro»vn parado\, which students of science, who 

 should have known better, have been ready to support. 



In Section A, on Monday, Aug. 28, Prof. Sylvanus Thompson 

 blandly occupied nearly an hour of the meeting's time with a most 

 monstrous theory as to the origin of hail — a theory- advanced ori- 

 ginally by Prof. SchwedoCr, but adopted, or at least supported, by 

 Prof. Thompson, despite its manifest absurdity. After describing 

 some very large liailstones, including one (whose description was 

 received by the meeting with irreverent laughter) as large as an 

 elephant, and three days a-melting. Prof. Schwedoff contended in 

 this p«J>er that hail is not of atmospheric origin, generated from 

 moisture suddenly in aerial storms, but comes from ultra-terrestrial 

 regions. In short, hailstones, according to this portentous theory, 

 arc meteors of cosmic origin. 



Of course, with interplanetary space occupied, according to Dr. 

 Siemens' ingenious paradox, by aqueous vapour, nothing would 

 be more natural than the formation of crystalline masses of water 

 in eitm-terre.itrial space. These, wherever found, would be drawn 

 sunwards, one would suppose ; and the only way in which they 

 could encounter the earth would be when they were formed outside 

 the earth. Then, if they were drawn towards the sun when it was 

 in the way, they would fall on that side of the earth which was 

 furthest from the sun — that is, where night was in progress. If 

 hail always fell in the night, this would be a very ingenious theory 

 by the way ; only, oa a matter of fact, hail falls oftener in the 

 daytime. 



Sir W. Thomson at once rose to his feet, when his almost name- 

 sake had concluded, and asked whether this meteoric theory of the 

 origin of hail was put forward as a joke ? He showed that meteoric 

 hail falling through the atmosphere with jilanetary velocity would 

 perform 13,000 times as much work as would raise water one degree 

 centigrade, which — he rather thought — would molt the hailstones. 

 Here occurred one of those little scenes which occasionally lighten 

 the dreary work of scientific talk-fights (the most utterly time- 

 wa«ting occupation I know of). Lord Rayleigh slyly said ho had 

 heard of another meteoric theory, which some said was advanced 

 in jest quite as much as Schwedoff's— the theory that meteors, 

 fragments of a burnt planet, may have brought the germs of life 

 to this earth. ("The Kettle to the Pot objects," ho seemed to 

 hint, " its arirdid superficies.") But Sir W. Thomson repudiated 

 the suggestion of jest in his notorious germ theory. He 

 did not himself think, he said, that life as it now exists 

 on this earth had sprung from meteoric visitants, fragments of a 

 pUnet which had burst millions of years before ; but he maintained 

 that it could not l>e proved to be impossible that some forms of life 

 might thus bo brought to a planet (wherefore Sir W. Thomson 

 most have Ijccn very imf«erfertly reported at Edinburgh). Neither 

 can it be abnolulely proved to Ix,- impoRsihle that the moon is made 

 of green cheese. If we assign to the meteoric germ theory the 

 iding that wo give to the theory of the verdant cascity of 

 will not l)e much the worse for cither. Professor 



the I 



SchwedolTs theorj- stands on about the same footing. It is utterly 

 nnlikely that ice-masw>8 exist in interplanetary space ; still more 

 utterly utter is the improbability that such masses could reach the 

 earth onmclted. If they did reach the earth, they would not show, 

 as hailstorms do, a preference for some regions and an utter 

 dislike fcT otheri (Peru, for example). Still, the theory is not 

 m'.re inroncivab'y improl^ble than Sir W. Thomson's germ theory, 

 or than llio thoory I formed myself, " in the days of my" scientific 

 "youth," that the mo<m'K whiLeni-ss (she b<'ing really more ncurlv 

 hUrk than white) i> <lii.- t., «tiow on h'r plains, and slopes, and 

 I sides. 



.;* 



f^0f/^'^[S^y^ 



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thftn fixity of opiuion." — Faraday. 



*' Show me a man who makes no mistakes, and I will show you a man who has 

 done uothiDg."—lAebig. 



ALCOHOL AND BRAIN WORK. 



[536] — I think I can recognise the " learned friend " of whom 

 you speak in your answer to the fiery denouncer of "fire-water," 

 and perhaps a little more detailed information may be of use to 

 you and others, from one wlio is as near as can bo to a teetotaller 

 from infancy, and yet may be said to bo infinitely difTeront from 

 one, as the smallest known quantity is infinitely more than nothing. 

 I am utterly indifferent to pliilosophy, whether alcohol is "poison," 

 as milk is in excess, or " food," as castor oil is partially, or a con- 

 stituent of the brain, as phosphorus is, or whatever anybody may 

 choose to say that it is or is not. 



I was four years at Cambridge, beginning nearly fifty years ago— 

 a far more bibulous time than now— without over drinking a glass 

 of anything stronger than the college " swipes " given us at dinner, 

 and occasionally a glass of the much bettor alo at a parly, having 

 been reared without even that, and disliking wino and spirits still 

 more to this day. And I did much tho same after I camo to 

 London, until I gave up even that small quantity of alcoholic _ 

 drink — I forget for what reason ; and I thought I did as well with- 

 out it. But soon after I pot into largo practice at tho Bar (without 

 a scrap of notice, which I thought very unfair and unusual on tho 

 part of Nature), I became unable to sleep, often for several nights 

 together, and never well except after somo very bad nights. I 

 guessed at tho cause, and turned on my beer again, and gradually 

 mended, but not completely for five years. After that I turned my 

 beer into a daily half-pint of cider (in what the British merchant, 

 the type of honesty all over tho world, calls a jiiiit bottle, with a 

 false bottom which seems annually to increase), because I found 

 beer tended to rheumatism and some kidney ailments, of which 

 last, cider is a well-known preventive — at least to doctors in tho 

 cider counties, though to very few elsewhere, it seems. 



That is my experience as a man working with my brains. My 

 earlier experience as a worker with logs and hands was that 

 alcohol is of no uso whatever, and that seems to have boon proved 

 over and over again. I must add that I have known ono man of 

 considerable ago able to go on doing hard work with his hood on 

 tectotalism, though I have known sundry, like myself, think they 

 were doing very well on it for a time, and I have heuril of a few 

 others. Of course, that proves that some may while others cannot, 

 and it may bo worth everybody's while to try tho o,\|HTimont ; 

 but they had better watch it carefully, for fear Nature sIkjuUI play 

 them tho same trick as she did rao, and comedown upon them with- 

 out notice. Tho cleverest doctor I over knew, now dead, though 

 tho manager of a water-cure establishment, used to toll me tho 

 same, and particularly that he had annually to euro with a littlo 

 disguised alcohol the "leader of somo teetotal society who used to 

 come there annually for " wator-curo," as ho supposed. 



Youii " Lkaunki) Fkiend." 



ALCOHOL AS A FOOD. 



[537] — I have never in my life (not oven when young and merry) 

 known what it is to be intoxicated. I cannot find words to describe 

 adequately tho feelings of disgust, shame, and jiity that a drunken 

 man inspires mo with, I dislike, and do not often visit, public 

 places, but when for the snko of friendship I hnvo to do so, tho 

 conventional small measure (one-eighth of a jiint) of spirits dis- 



