To the Editor of the Now-Cutxa Day News"
'Sm—The explanation offered by! Mu. F, J. Saxcen in his letter in your paper' of August 19 as to how a Jkarden spider' gels the main support-{ng strand of its web in position between tivo points at o considerable height above the ground may be correct in some cases, that is to say, the spider might let out a strand of web from some high point of vantage and allow it to be wafed by the wind to some other similorly" high point of vantage where it could become entangled. If such a method is ju actual fact employed, it must. be the exception rather than the rule, since itis certain that the spider Seems {o prefer to crawl {rom one vantage point to another as described ju my letter of August 14, which apeared in your issue of August 16, Notably would the—wind-wafing method seem to be the only feasible Jone in a ease in which a spider builds web over a stream, as has been observed, with the mein strands at~ schod to, points on both banks. But personally have never observed this method being used, and T find that in books dealing with the subject it {Ig offered more as the only possible theory to account for the positions of spiders' webs in such cases as here [suggested than 95 proven fact.
Tu my garden the crawling method certainly the one used, for the prevailing summer breezes are in the wrong direction for the operation of the wind-wafting method. Also it is highly improbable, with the vagary of breezes, that, if this method were used, the webs' would be in excelly the Same positions night after night, they are in my garden, 'As regards the point raised Mu. Saxeen as to whether the spider' proceeds continuously in one dirce-{ion while putting in place the spiral eross-webbing or reverses its direetion at intervals, 11cm of the opinion that it does the former. The crosswebbing of a garden spider's scare ik laid inthe form of a regular spiral, the spider commencing with It from the centre of the radial strands and javorking outwards to the citeum= Terence of the snare. If the spider laying this spiral cross-webbing. were to proceed just so far in one. direction and then reverse Its dirce= tion the result would be anything but a regular spiral, as can easily be proved by drawing a series of radial Hines and then ying to draw ina regular spiral as constructed by the spider by reversing direction 74 In. tervals. It cannot_be done. Mr, Saxcrn says that the spider in puts {ing in. the spiral erocs.webbing pro-coeds first in one direction and then the other at intervals. If this im= pression has been gained by observa ion. is he quite sure that, when the spider reversed its direction, it was laying down the cross-strands of the web and was not performing. some other function By his reference to a giddy goat 1 suppose he is suggesting that the spider might get giddy if it continued to go round and round in one direetion. while constructing IS snare. might remark that going round. in circles does not make one giddy. Tt fg spinning on one's own access thet does this, Also, there is no reason assume that, because 'a human being. or a goat, gets giddy by doing this. a spider would be affected in the same way.
Finelly, If may be allowed to tur from zoology' 10 philology for a moment, T would suggest that Mu. Saxicen's use of the word "animistie* in connection with a diseussion on a. biological phenomenon Is altogether wrong. Webster's dictionary ives "animistic" as "pertaining to animism." and defines "animism™ as "the doctrine that the soul Is the vital principle." What possible con: nection can this have with the methods adopted by a spider in building its web?
Anmiun De C. Sowrney.
Shanghai, Aug. 20, Points of Agreement To the Editor of the Nowrit-Cutna Dany News"
Sim-—Mr. Sowemny and I agree that the wind-swept construction method is sometimes used. Is it not interesting that the free end is allowed to float when a horizontal is desired, whereas the spider uses herself as a plumb-bob when making a vertical? Unless 'a makeshift boat (ferried by a water= boatman?) is used or a dragon fly, for instance, lends assistance, the main horizontal aerose a slreain must bbe carried by air currents.
The spider T was thinking about, when writing disregarded books ly—evidently an uneducated spider—for it not only reversed. its direction occasionally but also worked fon a diminishing radius when termi the spiral. 'The usual spiral is eon Ainuous perhaps and this was just a contrary' female, Giddiness may be due to. many causes other than rotation on one's axis; apart from diseases "of" the widitory labyrinth any rhythmic
circular canals can, I suggest, Tead to the illusion of a continuation of the motion causing. that disturbance. Walking ina circle is, however, a volation in one's axis plus translation in a elreular path as is obvious if the radius of the path is reduced until it approaches zero, when only rotation remains, "My Use of "animistic" was in eon-jon with our last discussion at the which came down to "Animism "Materialism" in the end, There be people who think that a spider has a mind but that was not suggestion and T donot credit Sowensy with that belief Shanghai, Aug, 23,
Text read from the printed page and cleaned; old type leaves the occasional error.