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NATURE 



[Nov. 7, 1889 



>*hole surface of the earth, and the value of an attemp '■. at such 

 ^ task would now be extremely doubtful. But fjr limited dis- 

 tricts, like this country, the case is very different. It would 

 indeed be difficult to over-estimate the value of a seismic record 

 Vhich can claim any approach to completeness for a definite 

 Earthquake area, however feeble the shocks which visit it may ba. 



I may add that I hope shortly to publish some notes or direc- 

 tions for the study of earthquakes, with spscial reference to those 

 which occur in this country. Charles Davison. 



38 Charlotte Road, Birmingham, October 10. 



Effects of Lightning. 



I HAVE known of the following case since July last, but owing 

 to absence from this place have only been able to get particulars 

 during the last few days. 



During the terrific sto'-m of the 12th of July last, a labourer's 

 cottage was struck by lightning at Leagrave, near here. The 

 lightning descended, according to an eye-witness's report, like a 

 "spout of fire," and struck and descended the chimney, which it 

 destroyed. In the room below there was an old shepherd, an 

 invalid woman, a child, and a shepherd's dog. The shepherd 

 was sitting in a chair leaning on a stick, a kettle was l)oiling on 

 the fire, and the door was open. The lightning entered the room 

 simultaneously by the chimney and an adjoining window. The 

 window was utterly destroyed, and the kettle was thrown from 

 the fire across the room, the stick on which the shepherd was 

 leaning was torn from his hand and also thrown across the room, 

 the lightning entered a cupboard containing glass and crockery 

 and destroyed every article, and plaster was torn from the walls. 

 The man and woman remained unhurt, but the child was thrown 

 down and its knees stiffened. The dog was struck perfectly stiff, 

 "like a log of wood," and was considered dead. The room 

 seemed full of fire, water, and sulphur, and the occupants said 

 the smell of sulphur was so strong that they would certainly have 

 been suffocated had it not been for the open door. After the 

 storm had abated, the dog, with all its limbs stiff, was laid in a 

 barn, where it very slowly and partially recovered. It long re- 

 mained both deaf and blind, anJ was entirely dependent upon 

 smell for its recognition of persons and things. To the present 

 day it has not entirely recovered its injured senses. 



Dunstable. W. G. S. 



Electrical Cloud Phenomenon. 



A SHORT description of a curious cloud appearance observed 

 by me this summer may be of interest to your readers. It was 

 noticed in Kiushu, the southernmost of the three great islands of 

 Japan, early in July, at a distance of ten or twelve miles from 

 the sea. 



The season had been, and was, after the time of the observa- 

 tion, an exceptionally rainy one, severe floods being produced in 

 almost all parts of the country, but it was not raining in the place 

 where I made the observation at that particular time. Time shortly 

 after midday, thermometer about Sj" F. 



The sky was clear overhead, but there was a great bank of 

 heavy " thunderous " looking clouds to the south. It is most 

 difficult to judge even approximately of the distance of clouds, 

 but these might b;; from one to two miles off; the lower edge 

 was represented by a very nearly straight line, and there was an 

 amount of blue sky visible under the clouds that would perhaps 

 subtend from ic° to 15°. 



My attention was attracted to a sort of "tail" of cloud 

 stretching itself downwards from the straight under side of the 

 cloud-bank. It gradually extended till it reached some two- 

 thirds of the distance from the cloud to the earth. It remained 

 of about constant length for a little over ten minutes, the lower 

 end continually waving about in a most curious way, giving the 

 impression almost that it was feeling for something. 



Quite suddenly the filament of cloud straightened itself out, 

 and extended itself towards the earth. The lower end became so 

 very thin that, from the distance, it was impossible to see whether 

 it actually made contact with the earth or not, but I have not the 

 smallest doubt that it did, and that a silent discharge took place 

 at the tioie. There was certainly no sound heard. Immediately 

 after the contact the filament rapidly drew itself up to the cloud, 

 and was incorporated with it. Almost immediately after this, 

 whether as a mere coincidence or not I cannot tell, the cloud 

 discharged a great amount of rain. VV. K. Burton. 



Imperial University, Tokio, Japan. 



P. S. — The appearance was not unlike the illustrations o^^ 

 "water-spouts" that I have seen, but there was no whirling 

 motion such as is always described as accompanying these, nor, 

 indeed, was there any evidence of violent disturbance of any 

 kind at all. 



The Use of the Word Antiparallel. 



The following note on the use of the word antiparallel may 

 prove of interest to tiie readers of Nature. 



In the second edition of " A New Mathematical Dictionary" 

 by E. Stone, F. R.S. (London, 1743), appears a short article on 

 antiparallels, the whole of which I will quote : — 



" Antiparallels, are those lines, as FE, BC, that make the 

 same angles AFE, ACB, with the two lines AB, AC, cutting 

 them, but contrary ways, as parallel lines that cut them. But 

 Mr. Leibnitz, in the Acta Erudit., An. 1691, p. 279, calls 

 antiparallels those lines (see Fig. 2) as EF, GH, which cut two 

 parallels AB, CD ; so that the outward angle AIF, together 

 with the inward one AK.M, is equal t3 a right angle. When 



E a 



the sides AB, AC, of a triangle, as ABC (Fig. i), are cut by 

 a line EF antiparallel to the base BC, the sa^d sides are 

 cut reciprocally proportional by the said line EF ; that is, 

 AF : BF : : EC : AE, the triangles AFE, ABC being similar or 

 equiangular." 



The error in regard to the ratios of the segments of the 

 sides is the same as the one noted in Mutton's "Miscellanea 

 Mathematica," as quoted by Mr. Langley. I have no doubt that 

 earlier instances of the use of this word can be found, and I 

 would like to know whether the word is used in the first editio.i 

 of "Stone's Dictionary." W. J. James. 



Wesleyan University, Middletown, 

 Conn. U.S.A., October 15. 



Fossil Rhizocarps. 



In Bennet and Murray's "Cryptogamic Botany," at p. 115, 

 I am surprised to find in a reference to my paper on " Fossil 

 Rhizocarps " (in Bull. Ac. Sciences, Chicago) the statement, with 

 reference to the macrospores of Protosilvinia, that "inasmuch 

 as they are borne on LepidodenJron scales this reference is in- 

 admissible." Now no such fact has come to my knowledge, 

 and on the contrary these bodies are found inclosed in cellular 

 sporocarps like those of Salvinia, and are so described in the 

 paper in question. If anyone has found them on " scales of 

 Lepidodendron," the authority should have been stated. 



Montreal, October 15. J. Wm. Dawson. 



Specific Inductive Capacity. 



On p. 669 of Ganot's "Physics" (eleventh edition) the 

 following statement is found:— "At a fixed distance above a 

 gold-leaf electroscope, let an electrified sphere be placed, by 

 which a certain divergence of the leaves is produced. If now, 

 the charges remaining the same, a disk of sulphur or of shellac 

 be interposed, the divergence increases, shoving that inductive 

 action takes place through the sulphur to a greater extent than 

 through a layer of air of the same thickness." 



If this statement were correct, there should be less electric 

 action on the side of the ball furthest from the electroscope when 

 the dielectric is interposed. To test this I arranged an experi- 

 ment as follows : — 



The knob of a charged Leyden jar was placed midway 

 between two insulated plates of metal, each plate being in 

 connection with an electroscope. The leaves of each electro- 

 scope now diverged to an equal extent. 



A plate of ebonite was now placed between the knob of the 

 jar and one of the plates. If the statement above quoted is 



