April 5, 1894] 



NA TURE 



OJ 



While I regret having incorrectly inferred Mr. Hannay's 

 claims, readers of the paper to which he refers will, I think, 

 perceive that the error was not without some justification. 



Trinity College, Dublin. J. Joly. 



The New Comet. 



The comet discovered here on March 26 was re-observed on 

 the 27th, 28th, 29th, 30th, 31st, and April ist, 2nd, and 3rd, 

 and its places on four nights were determined as follows : — 



1894 G.M.T. R.A. Decl. 



h. m. h. m. s. . , 



March 26 ... 9 30 ... 9 54 37 ••• +32 13 



27 ... 10 30 ... 9 58 32 ... +31 38 



30 ... 9 50 ... 10 9 12 ... +30 I 



31 ... II 15 ... 10 12 48 ... 4-29 27 



The motion is becoming slower, whence it may be inferred that 

 the perihelion passage occurred some time ago. 



The cfimet is small and faint, with a stellar nucleus of about 

 I2th magnitude and a short fan-shaped tail. It was discovered 

 with a 10 inch reflector and comet eyepiece magnifying thirty 

 times. To my eye the comet is now decidedly more obvious 

 than it was when first seen, but this may either be due to more 

 favourable atmosphere, or to the fact that greater familiarity with 

 an object is apt to render it plainer. 



Bristol, April 4. W. F. Denning. 



Sun spot Phenomena and Thunderstorms. 



A SMALL portion of that most interesting field of research 

 again dealt with in Nature (vol. xlix. p. 503), perhaps 

 requires to be trodden with caution. Of course all a friori 

 reasoning as to probabilities of a connection between solar 

 physics and the occurrence of thunderstorms may be laid aside, 

 and it does not seem that writers on the subject have fallen into 

 that kind of anti-scientific error. At the same time, we readily 

 admit that a connection between solar activity and thunderstorm 

 phenomena exists. But having devoted a little time to the 

 consideration of the question, I may be permitted to make a 

 remark. In the first place, so far as our observations at present 

 •extend, it is quite impossible to find a distinct relation of time 

 between prevalence of thunderstorms over our planet and solar 

 periodicities. In the second place, thunderstorms have been 

 classified, and much require further classification (to which, by 

 the way, I am just about to contribute a few results of study). 

 Artificial or conventional classification would by no means be 

 an object of pursuit to Dr. Veeder. Natural classification does 

 not seem to bring us now at all near to the connection which 

 we might anticipate. In fact, it seems to me that in reference 

 to the thurderstorms mentioned in Nature for March 29, 

 1894, natural classification leads us away from the connection. 



April 2. W. Clement Ley. 



A Lecture Experiment. 



The following experiment, to illustrate the anomalous con- 

 traction and expansion of water due to decrease of temperature, 

 I have found to be very striking : — 



A large test tube is fitted with a cork, through which a glass 

 tube passes just far enough to allow a rubber tube to be 

 attached. The rubber tube should be long enough to reach 

 to the bottom of the test tube. Close the lower end of the 

 rubber tube, and fill it and the glass tube with mercury up to a 

 little above the top of the cork. Fill the test tube with water, 

 insert the rubber tube, and cork and press the latter firmly in 

 place, taking care that no air-bubbles are imprisoned between 

 it and the water. The pressure of the cork against the surface 

 of the water will cause the mercury to rise in the ylass tube. 

 Place the apparatus thus prepared into a freezing mixture of 

 ice and salt. The mercury will fall slowly in the tube until the 

 water has attained its maximum density, remain stationary for 

 a moment, then rise on the further cooling of the water, and at 

 the instant of freezing will make a rapid movement upward. 



Armour Institute, Chicago, U.S.A. J. C. FoYE. 



Centipedes and their Young. 



The members of the Trinidad Field Naturalists' Club will 

 be glad if any of your correspondents can throw additional 



NO. 1275, VOL. 49] 



light upon the following facts in the history of centipedes, 

 which have recently cnme under their notice : — 



On September 17, 1892, Mr. Charles Libert, of this town, 

 sent to Mr. R. R. Mole a centipede {Scolopendra prasina) 

 which enclosed in a circle formed of the fore part of its body 

 a circular mass of young centipedes about the size of a half- 

 penny, and about quarter of an inch thick. The young ones 

 were quite white. The old centipede was very vicious. The 

 centipede and the young ones were exhibited at a conversazione 

 of the Victoria Ir.stitute the same evening. The old centipede 

 did not alter her position at all, and on the 2lst was packed 

 up for transmission to the Gardens of the Zoological Society, 

 London. Dr. Sclater wroie, on October 27, to Mr. Mole 

 stating that the centipede was dead on arrival, and only one 

 young one could be found in the box. Mr. Libert informs me 

 that he has once or twice found young cenii|iedes clinging to 

 various parts of the body of an adult. Mr. T. D. A. Cockerel! 

 (late of Jamaica), of whom inquiries were made, said this 

 habit was new to him. 



At a meeting of the Trinidad Field Naturalists' Club on 

 July 7, 1S93, the President (Mr. Caracciolo) exhibited a 

 sketch of a centipede carrying its young between the legs of the 

 anterior twelve segments of its body. He stated that he 

 received the centipede, from which the sketch was made, from 

 Mr. Guiseppi on June 20. The creature protected her young 

 in this manner until June 25, when she altered her position, 

 and lay flat over them. On June 30 she left them, "but kept 

 an eye on them." When undisturbed the young centipedes 

 formed a heap, in which they remained for f(jur days. They 

 then gradually began wandering away from the heap, one by one, 

 in search of food. There were about 140 young ones altogether. 



At the meeting of the Club on February 2, 1894, Mr. Potter 

 said he had been told by Mr. S. W. Knaggs that he had 

 recently found a centipede coiled up spirally on itself. On 

 attempting to uncoil it a number of pellets of small size fell 

 from its under-surface. These bore the appearance of eggs. 

 He subsequently found others clasped by the numerous legs 

 against the creature's under-surface. The pellets, or eggs, were 

 situated all along the under-surface of the body, and dropped 

 from it on its being uncoiled. 



Several text-books and works on natural history have been 

 consulted with the view of finding out more about this interest- 

 ing habit, but without success ; and in most books it is stated 

 that centipedes lay their eggs under dead leaves, or in a dark 

 corner, and manifest no further concern about them. 



F. W. Urich. 



Port of Spain, Trinidad, B. W.I., March 6. 



PROF. IRA REMSEN ON CHEMICAL 

 LABORATORIES} 



ON January i the Kent Chemical Laboratory was 

 dedicated with appropriate exercises. The beau- 

 tiful building was thrown open to inspection, and many 

 passed through its rooms expressing admiration. Its 

 plans were explained and a general account was given 

 of the uses to which it is to be put. Honour, "as is 

 most justly due," was paid to the generous donor, whose 

 name from this day forth will be intimately associated 

 with progress in chemistry in this country. The exer- 

 cises of yesterday have led by an easy step to those of to- 

 day, and a chemist is called upon to give the Convoca- 

 tion address. What theme more natural to him, or more 

 appropriate, than " The Chemical Laboratory .'' " It is 

 to this theme that I ask your attention. My purpose 

 is to treat the chemical laboratory, not from the ma- 

 terial point of view, but in its broader aspects, as far 

 as I may find this possible. I shall attempt to answer 

 briefly three questions, and these are : — 



(i) When and how did chemical laboratories come to 

 be established in univ^ersities .'' 



(2) What part have chemical laboratories played in 

 the advancement of knowledge .'' 



' Address delivered by Prof. Ira Remsen on January 2, 1894, in connec- 

 tion with the opening of the Kent Chemical Laboratory of the University 

 of Chicago, U.S.A. 



