July 5, 1883] 



NA TURE 



225 



limited area, and mostly in unconsolidatad bed-, and it is quite 

 probable that they would not outlast the destructive influences 

 to which they are subjected if these were continued throughout 

 a geological period. The coast-line occupied by flint-shingle is 

 almost limited to portions of Western Europe, and is relatively 

 insignificant. J. S. Gardner 



Science Club 



The Great Comet i 1882 



M. Raoul Gautier, of Geneva, has recently published, in 

 Astronomischc Nachrichten, No. 2519, three sets of elements of 

 this comet, calculated from a few observations before perihelion. 

 He says that, as it is possible to represent with the same 

 curve, either a parabola or an ellipse, the nearest observations 

 before and after perihelion, he believes "que si la comete a subi 

 une perturbation dans son mouvement lorsqu'elle a passe a son 

 perihelie, cette perturbation a du etre insensible." 



As I am not so far advanced with my calculations, for I have 

 begun a thorough discussion of the movement of that comet, 

 I do not know whether there has been or not any considerable per- 

 'urbation during the passage near the sun ; but can the simple 

 fact alluded to by M. Gamier give us much information on that 

 point? 



In fact, we can easily understand that although the orbit after 

 perihelion might be quite different from the orbit before that 

 point, still the positions of the comet at a short distance from 

 perihelion may be pretty well represented, within the limits of 

 the errors of observations, by a single curve, which of course 

 will be of second order, but which will not certainly give the 

 calculated positions of the comet at a certain distance from peri- 

 helion agreeing with the observations. If we could prove that 

 the orbits calculated, for instance, from observations between 

 September 7 and 12 and between the 22nd and the 30th of the 

 same mon'h agree together, and give the positions of the comet 

 immediately before and after perihelion according to the obser- 

 vations, then we could say that the movement of the comet was 

 not perturbated during the passage near the sun. But this 

 fact is not proved at all, and instead it seems that the passage 

 through the corona has had some effect upon the movement of 

 that remarkable comet. E. Ristori 



13, Pembridge Crescent, Bay-swater, June 16 



This comet was visible here with the naked eye up to 

 February 28. I so saw it myself on the evening of that day. 

 Owing partly to cloudy weather, partly to moonlight, I had not 

 seen it for ten days or a fortnight previously, but found it on that 

 evening with little difficulty and without any optical help. In 

 my telescope (4-in.) it appeared, roughly, like a long, flat-sided, 

 oval nebula, the central part of the major axis being the hi ightest 

 of the whole. Two cloudy evenings intervened, and on the fol- 

 lowing night (March 3) I could not see it with the naked eye, 

 even after finding it with the telescope and knowing exactly 

 where to look, and though the optical condition of H12 air 

 seemed the same. During April I saw it, with the same tele- 

 scope, on sixteen evenings, cloudy weather a id moonlight inter- 

 fering on the others. In the present month (May) 1 saw it five 

 times, that is, up to the 6th certainly, and I believe I saw it on 

 the 9th, but decreasing visibility and increasing moonlight pre- 

 vented verification. I have just received a somewhat larger 

 instrument (S-in.), with which after the moon has passed I hope 

 to see it again. A. S. Atkinson 



Nelson, N.Z., May 19 



Sun Pillar seen in Jamaica 



At sunset on May 15 I saw for the first time in my life the 

 phenomenon called the Sun Pillar. A few days later the mail- 

 packet arrived from England, and in Nature I found much 

 correspondence on its appearance on April 6 at several places in 

 England and Wales between Hull and St. David's. 



Major Gibney's admirable description of its general appearance 

 on April 6 (vol. xxvii. p. 605) was so fully confirmed on May 15 

 in Jamaica that a very brief description may here suffice. 



At 6h. 30m. p.m. Kempshot mean time it appeared as a bright 

 ray of light of a faint roseate hue, 2° in width and 30* in height 

 above the horizon, vertical, but not passing through the sun. A 

 rough sketch was made at the time, and the circles of the equa- 

 torial were afterwards employed to determine the azimuth of the 

 point where the pillar cut the horizon. This was 70° from the 



north towards the west ; and as the sun's azimuth was 69° at 

 the same time, the pillar passed i° to the west of the sun. In 

 the sketch the pillar is represented as passing its own breadth 

 to the west of the sun, but as the sun was then just below the 

 horizm the former measure is likely t > be more correct. 



Now with regard to the nature of the phenomenon, it cer- 

 tainly was not the usual display of the zodiacal light. The light 

 is here seen to perfection ; every h le night when there is no 

 moonlight the zodiacal li/ht may be seen following the ecliptic 

 from the one horizon to the other with but little variation, except 

 perhaps as to the gsgenschein or stronger illumination near the 

 point in the heavens diametrically opposite to the sun. And so 

 clearly is it seen, that >ome years ago I carefully measured its 

 breadth at different distances from the sun, and so formed the 

 following table : — 



From various considerations based upon the figure correspond- 

 ing to these measures I consider the zodiacal light a terrestrial 

 phenomenon — rays of light are swept back from the sun, chiefly 

 from the tropical parts of the earth, and tend to accumulate at 

 the point in the heavens diametrically opposite the sun. 



If there be any truth in this theory, the sun pillar may be a 

 strong and comparatively local development of the same light ; 

 this is the only explanation I can give ; the explanation given 

 by Mr. G. J. Symons, the well known meteorologist, "that it 

 is merely a portion of a balo passing through the sun" (vol. 

 xxviii. p. 7), will not apply to the Jamaica observation at all ; 

 the sky was far too pure and transparent at the time, and there 

 was not the least trace of cirrus cloud. Maxwell Hall 



Kempshot Observatory, Jamaica, June 7 



Error in Hutton's Tables of Logarithms 



At the end of Hutton's "Mathematical Tables " (new edition, 

 1858, Longmans and Co., London) there is a very useful table 

 containing the logarithms of certain constants frequently used in 

 calculation. The tropical revolution of the earth in days is there 

 given as 365 24226, and the logarithm of this most important 

 constant is given as 2'56259io instead of 2'562s8io. 



I would be glad to know from any of your readers whether 

 there are any other important errors in this edition, especially 

 among those tables of logarithms in frequent use. 



Jamaica, June 4 Maxwell Hall 



Palaeozoic Sclerotic Plates 



In the course of my researches among the coal shales of 

 Northumberland I discovered two specimens of ossicular rings 

 known as sclerotic plates. The external diameter of one ring is 

 five-eighths of an inch, and the orbital orifice is one quarter of 

 an inch ; this ring of sclerotic plates consists of nine bones 

 arranged as are the eye bones of Ichthyosaurus, Plesiosaurus, 

 and eagles, viz. in tolerably uniform segments. The second 

 specimen is a quadrant of a ring, and consists of six plates of 

 larger size than the other specimen. I shall be glad to learn if 

 any of your readers have di covered similar sclerotic plates in 

 the Palaeozoic rocks of the British Isles, as specimens are not 

 exhibited in the British Museum, Jermyn Street Museum, or 

 Edinburgh Museum. T. P. Barkas 



Newcastle-on-Tyne, June 25 



Graft-Hybridisation 



St. Paul, in his Epistle to the Romans, sa y S ( c h. xi. v. 17), in 

 illustration of the admission of the Gentiles to the religious privi- 

 leges of the children of Israel, " If thou, being a wild olive, 

 wert grafted in among them, and didst become partaker with 

 them of the root of the fatness of the olive tree," &c. Olshausen, in 

 his commentary on this epistle, says (English translation, p. 369), 



