Aug. 11, 1882 



• KNOWLEDGE ♦ 



175 



-''d. V* A N I U;iiaIR^T ED . ^\Jf^ 



>^ MAGAZINE OF SCliENCE'^ 



^ P lMNLY^fORDED-EXACTLY PESCKIBED | 



LONDON: FRIDAY, AUGUST 11, 1882. 



Contents op No. 41. 



The Angust Meteors. Br the Editor 

 English Seaside Health - Resorts : 

 Winter Temperature. By Alfred 



'S^h! 



C.8., F.R.M.C.i 



The Humour of the Aryan Race ... 

 Forms of Clouds. By the Editor. 



(lUuttrated) 



Learning to Swim. By Natator ... 



Reviews; Modem Dress 1m2 



Weather Charts for the Week 183 



The PubUc Health 183 



Correspondence:— A Calculation- 

 Breathing through the Nose — 

 Fairy Rings i'. Ringworms — Brain 



Troubles— Bicycles 181 



Answers to Correspondents 1S6 



Science and Art Gossip 187 



Our Mathematieal Column 18S 



Our Chess Column 181) 



Our Whist Column lt» 



THE AUGUST METEORS. 



By the Editor. 



ON the nights of August 10 to 1-1, and sometimes till 

 several nights later, meteors or shooting stars, 

 belonging to the family known as the Perseides, may be 

 generally seen, at times showing in great numbers. Hum- 

 boldt remarks tliat, on the festival of St. Lawrence 

 (August 10), "fiery tears" (supposed to be the saint's) fell 

 from heaven, and he quotes Dr. Thomas Forster as saying 

 that in a manuscript preserved in the library of Christ's 

 College, Cambridge, written in the tenth century by a 

 monk, the 10 th of August is di.stinguished by the word 

 " Sleteorodes." Thomas Forster seems to have over- 

 looked the effect of difference of style. In the seven- 

 teenth century, when the style was corrected, eleven days 

 were dropped* to set tlie calendar right; in the tenth 

 century the difference due to stylo amounted only to si.K 

 days ; so that the worthy monk's day for " meteorodes " 

 corresponded to Aug. IG of our time. Tlie same meteor 

 system may be meant, however, as perturbations may have 

 affected tlie place where this family of meteoric bodies 

 crosses the earth's orbit. 



It is interesting to compare what was said about shooting 

 stars by Humboldt, forty years ago, with our present 

 knowledge. Then there were sensible men who saw, in the 

 knowledge already gathered, the means of determining 

 many points wliich writers in our time too often speak of 

 as if they were recent discoveries. Then, also, there were 

 representatives of the sterile scliool of science who ridiculed 

 the results of sound reasoning, as if it were a fanciful hypo- 

 thesis ; men who called themselves observers, and spoke 

 with enthusiasm of the making of observations, the col- 

 lecting of observations, the classifying of observations, of 

 everything, in fine, connected with observations, except 

 the attempt to understand them and determine their 

 value, which these cleverly practical persons called nifre 

 theorising. 



• The day following Sept. 2, 1752, was called Sept. It. In .wmo 

 po])uIar books of astronomy, Sept. 3 is subatitntod for Sept. 2, and 

 the sinRiilar statt'mont made that calling the day following Sept. 3 

 Sept. 14, involved dropping e^ei'fn days. — I i<!e Lockyor'a "Elements 

 <of Astronomy," and other snoh works. 



Thus Olmsted at Newhaven, Conn., found that during 

 the celebrated fall of shooting stars on the night between 

 November 12 and 1.3, 183.3, the fire balls and shooting 

 stars all radiated from one and the same quarter of 

 the heaven.?, namely, the vicinity of the star Gamma 

 Leonis, and did not deviate from that point, though the 

 star changed its apparent height and direction with 

 regard to the compass points during the time of observa- 

 tion. A curious observation — to be recorded, sent to some 

 learned society, and forgotten 1 Not altogether £o. 

 Olmsted had a brain, as well as eyes wherewith to observe, 

 and he reasoned that " such an independence of the earth's 

 rotation shows that the luminous body must have reached 

 our atmosphere from vdthont. A fanciful theory, truly, 

 said in effect the mere observers, for they proceeded to 

 speak of meteors as though nothing of the kind had been 

 shown. The fact is, however, they were to be excused : 

 Olmsted's reasoning was demonstrative only for those who 

 could follow him ; he could give reasons, he could not give 

 understanding. 



So also, the occurrence of showers on particular days of 

 the year — that is, at times when the earth is in particular 

 parts of her orbit round the sun — was recognised by 

 reasoning men as proof positive that meteor systems are 

 extra-terrestrial. Humboldt, though he was not, properly 

 speaking, an astronomer, yet studying astronomy like other 

 sciences, with care to obtain an insight into the facts, saw 

 the real meaning of this particular fact. 



Noiv, of course, what was proved half a century ago by 

 Olmsted, Encke, and others, is the accepted teachuig of 

 science. The August shooting stars gave the first obvious 

 and easily understood evidence on the subject. When it 

 was noticed that the larger comet of lf<G2 crossed the 

 earth's track where the August meteors are encountered, 

 every one could understand what Schiaparelli meant when 

 he said that bodies following in the track of that comet 

 would appear (as they passed through our atmosphere') to 

 follow such path as the August meteors traverse, i.e., paths 

 seeming to radiate from the constellation Perseus. The 

 beautiful reasoning of Olmsted had been neglected ; the bold 

 fancy of Schiaparelli was at once noted : not more noted 

 afterwards when by sound reasoning he showed that his 

 lucky guess was a true one, than when lie first threw out 

 tlie idea. What followed is or should be well known. 

 Adams, by an admirable mathematical investigation, 

 showed that the November meteors travel in a period of 

 33^ years round the sun ; and it was found tliat Tempel's 

 Comet of 1 8GG traverses the self-same track. Aftor which, 

 it was justly regarded as proved that tliese meteor systems, 

 following in the track of two comets, are in some way 

 associated with them, and that, therefore, probably other 

 systems of meteors are similarly associated with comets ; 

 and other comets, in like manner, followed by trains of 

 meteoric bodies.* 



The shooting stars, which will probably be seen during 

 the next few nights after these lines appear, may be iden- 

 tified with the Perseids by observing whether the paths 

 they follow — traced straight backwards — pass through the 

 constellation Perseus. Our Star Map for August (part 311, 

 for July 2S) shows that this constellation lies rather low 

 down towards the north-east — a little northerly — at 9.4.'") 



• A fact singularly misunderstood by many. Tims, in Mr. 

 Dunman's charming " Talks about Science, just issued, it is stated 

 that, according to " Messrs. Thompson " (Sir W. Thomson) "and 

 Tuit," the tail of a comet is " a cloud of dust from the colliding 

 masses" [of meteors] " which the head trails behind it." Mr. Tail 

 said something of the sort — in fact, ho wrote that a comet's tail is 

 merely a shower of paving stones ; but that was before ho know 

 what astronomers had really proTcd. 



