♦ KNOV/LEDGE 



[Oct. 9, 1885, 



nilU clinch irge of t 



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THUNDERBOLTS. 

 [1919]— I have frequently been struck by the fact of thnnderbolts 

 falling during violent storms, and of their simultaneous appearance 

 with flashes of lightning. 



That masses of matter occasionally accompany the electric fluid 

 when it reaches the earth there is no question ; they have been 

 seen and described as " balls of fire," and I have in my possession 

 one that fell some time ago at Casterton, in Westmoreland. 



It was seen to fall during a violent thunderstorm, and, killing a 

 sheep en route, buried itself about six feet below the surface, and 

 when dug out shortly after it was still hot. In appearance it much 

 resembles a volcanic bomb ; it is about the size of a large cocoa-nut, 

 weighs over 12 lbs., and seems to be composed of a hard ferrugi- 

 nous quartzite. I have not yet submitted it to a technical analysis, 

 but hope to do so shortly. " There is an external shell of about an 

 inch in thickness, and this contains a nucleus of the s,ame shape and 

 material as the shell, but is q\iite independent of it, so that the 

 one is easily separated from the other ; I attribute this separation 

 of the parts to an unequal cooling of the mass. 



I have often wondered from whence thunderbolts were derived, 

 and why they always fall as " balls of fire " accompanied by flashes 

 of lightning. 



It occurs to me that if ten millions of meteorites enter onr atmo- 

 sphere daily (vide Knowledge, Feb. 8, 1884), and become dissi- 

 pated into vapour on coming into contact with our air, that some 

 of these bodies might chance to survive the ordeal of passing 

 through the more rarified zones and reach the earth, if only an 

 airless passage could be obtained during the latter part of their 

 journey. 



By recent observations made on luminous meteors the height of 

 the atmosphere is calculated to extend to about 200 miles. The 

 pressure of the air at the sea-level being about 15 lb. per square 

 inch (subject to variation), the density at a distance of 200 miles 

 must be almost nil ; in point of fact, at about 3 miles from the 

 surface the pressure of air is reduced to 7^ lb., while at a little over 

 6 miles it is only 3| lb. per square inch, for " as the elevation 

 _.„-^, i:__, ;^jj_ Ijjg ciensity and pressure 



[hE i"I«H. 



efish, 



elevation of somewhere about 

 n tropical regions). I refer to 

 torm-clouds have reached this 



ly, but that thunderclouds 



Increases in arithmetical progi-ess 

 decrease in geometrical progression. 

 Clouds in Great Britain reach ai 

 6,500 ft. (being considerably higher 

 cirrus clouds. Whether nimbus or i 

 height in Great Britain I cannot 



usually at a considerable height is proved by the large drops of 

 rain that fall during a storm ; for the greater the distance the 

 drops have to fall the greater is the amount of moisture they take 

 to themselves on their passage throught a moist atmosphere. 



Electric storms have been observed at a height of 16,000 feet ; I 

 presume that this was not in Great Britain, but, of course, the height 

 of any particular storm-cloud may be ascertained by calculating the 

 timethesoundof the thunder takes to reach us (at a rate of 1,130 

 feet per second) from the moment the lightning flash is seen. 



Let it be granted then that the densest portion of our atmosphere 

 lies between any particular thunder-cloud and the earth, and that 

 this presents the most formidable barrier with which meteorites 

 have to contend when approaching us. Let it also be granted that 

 many (specially favoured) meteorites reach the regions of the 

 highest thunder-clouds from space before being completely 

 vapourised by friction. Then it is only required to find some medium 



.['■ 



[1950]— Referring to th. .■■•>• i . mii I i 



which you quote from tin 1 ... .=.="^ vi 



8ept. 11, I notice that Ml II ' nil y of trans- 



porting the fish of tropi. .il . I'M I'i II ■' .11" .- lliis I can 

 corroborate from bitter p(i>.(,iiai e.\i»-UuiiLus. i\ui culy fish, but 

 creatures so comparati\elyli inly organised as curals and molluscs, 

 die on board ship of something analogous to sea-siekncss, unless the 

 tanks containing them are " gimbal-swung." But it seems to me 

 that this undoubtedly great obstacle to the importation is not, after 

 all, so nearly insuperable as to give occasion for marvel at the 

 fact of two specimens of J/acrojwdus Hrir/iftarvs reaching the 

 States alive. Last week I saw a tubful of the closely-allied 

 Macrojwdus venustis-nmus, in capital condition exposed for sale 

 at the General Import Company's store, 177a, Euston-road, with 

 the curious so-called "stalk-e>ed" or telescope gold-fish, and other 

 singular denizens of Eastern rivers. I once availed myself of a huge 

 well-hung tank, originally constructed for tlie transmission of a 

 manatee from Guiana (the apparatus and freight had cost some- 

 thing like £100, while the cow died the day after shipment), to 

 endeavour to bring over some living flying-fish. They were put on 

 board in splendid order at Barbados : the time of year was favour- 

 able, and the steamer one of the swiftest on the West Indian route: 

 and I had prepared an arrangement whereby the temperature of the 

 water in the tank (changed daily) could be raised when necessary. 

 In fact, I spared no pains to ensure their safety, for I was offered 

 my pick of the serpents at nearly every zoological collection in 

 Europe In exchange for them— a very tempting bait to me. Yet 

 they all died before we sighted the Azores. They were isolated 

 from all rolling or pitching motion, but I suspect the vibration of 

 the engines reached them. Ahthue Stradling, C.M.Z.S. 



Watford. 



M i Ml T.riKATIIIXO-ST.VMMERING. 



i . :i!.. ■■ K..i..ki.rs ■ .loire, in middle age, to use 

 :i;:il n:ii-ir, I mn ilnJn.LT it mvself in another 

 brail. h- I -i: ■ Willi 111.' wwli t(. i.lra.-.;., not torture, my unlucky 

 hearers, 1 am tiying in pri-paii- myi-elt thoroughly. 



The very first step I took opened out new worlds to me, in other 

 directions, by teaching me hoiv io hreathe. I never knew before. I 

 now find very few people who do know. Almost every one I meet 

 on a tricycle or bicycle has his mouth open, thereby indicating a 

 difliculty of breathing. An exceptional rider shut his mouth while 

 looking at me in passing, but opened it again as soon as he got by. 

 Although an athlete of some experience and success, I had always 

 handicapped myself, and even endangered my health, by false 

 breathing with the upper part of the chest. In many sports and 

 handicrafts the muscles of the upper part of the chest are on a 

 strain, and fix the chest walls so much as to render breathing by 

 means of them both difiicult and unnatural. One cannot easily 

 expand the lungs against the opposition of so many muscles and 

 the weight of the shoulders. The effort required to do it prema- 

 turely exhausts one, and evidently was never intended to be made. 



On the other hand, when the diaphragm is used to expand and 

 contract the lower part of the chest, the operation of breathing 

 becomes perfectly easy. One's attention and energy are left free for 

 the work in hand. One soon feels that the diaphragm was made to 

 work the bellows, and one notices a welcome change in the aeration 

 of the blood and the working of the heart. 



I took up tricycling some eighteen months ago, and thought it 

 rather an exhausting pleasure. But for the last six months I have 

 been working at singing, and from that time have really believed 

 there might be some truth in the enthusiastic cj-eling screeds one 

 reads. I found that with diaphragmatic breathing 1 could do any 

 amount of work without feeling nervous or exhausted. I can suit 

 my breathing to my work with the greatest ease. In fact, I have 

 been surprised to observe that I never think of my breathing even 

 up the steepest hills I ride. I note a similar improvement in 

 walking. 



Now, in the same way, stammering may be benefited. Of course, 

 that term includes many ailments and eccentricities of speech, 

 some of them depending on individual organisation which God has 

 not given us the power to mend. But the art of breathing has now 



