404 



NA TURE 



[August 2 1, 1879 



arrano-ed that it 15 scarcely worth while to particularise them. 

 Of course the battery current thus liberated by the excited current 

 could be used for controlling other clocks. _ 



The effect on the pendulum is thus restricted to the quicker 

 parts of its swing ; and consists of slightly retarding the descent, 

 and accelerating the ascent, apart from all mechanical friction or 

 contacts. Thus each action is produced at the most suitable 



Possibly a pendulum cutting off heat rays from a thermopile 

 mi^ht thus work a switch, and be even less affected than by 

 producing an excited current in the coil-bob, as propose* above. 



Bromlly, Kent W. M. Flinders Petrie 



Did Flowers Exist during the Carboniferous Epoch ? 



Noticing in your pages under the above heading a discussion 

 on /"jw/ butterflies and moths, &c., and being struck with the 

 deep interest taken in the question as evidenced by the letter of 

 the Rev. A. E. Eaton (vol. xx. p. 315), I thought that I would 

 ask for a very small space for an intercommunication which may 

 forward investigation. 



I have in my collection what appears to me to be a butterfly 

 (using the word without any regard to scientific nomenclature), 

 as a carbonaceous impress on a piece of shale from the 

 Slievardagh coal-field, Tipperary ; and by way of contril>uting 

 my mite towards an inquiry which it gives me pleasure to find so 

 earnestly pursued, I shall be happy to forward the specimen for 

 examination to any of the scientific gentlemen interested who 

 will furnish me his address, or in turn to as many as it will be 

 convenient so to accommodate, on condition thai the specimen he 

 return: d to me in good order and without unreasonable delay. 



I may be allowed to add that I have no sympathy whatever 

 with the discussion in its present bearings. 



Earlshill Colliery, Thurles, August 7 William Morris 



" Euclid and His Modern Rivals " 

 Mr. Dodgson thinks "it worth while to point out a mistake 

 made in the paragraph about Mr. Morell's book" (Nature, 

 vol. XX. p. 240). In the words " the thing not being capable of 

 proof," the "thing" referred to is Mr. Morell's assertion that 

 '■the perimeter MDQRSTM is less than the perimeter 

 M PQRST M," which is not necessarily true, and of course 

 is incapable of proof. Surely this assertion, which I quote two 

 lines before "thing" occurs, is its grammatical antecedent? 

 You refer it back to the theorem itself, which Mr. Morell is 

 trying to prove — a theorem which is true and easily proved." I 

 gladly accept Mr. Dodgson's statement, which is, if I remember 

 rightly — for I am here far away from Mr. Dodgson's book — 

 perfectly correct— and apologise for having inaccurately repre- 

 sented his meaning. 



The Writer of the Notice of 



"Euclid and His Modern Rivals" 

 Penzance, August 8 



SOCIETIES AND ACADEMIES 

 London 



Entomological Society,'August 6. — J. W. Dunning, M. A., 



F.L.S., vice-president, in the chair. — Sir. Philips exhibited 

 living specimens (both sexes) of Sperchetis emarginatus, taken at 

 West Ham. — Mr. Stainton exhibited, on behalf of Mr. Grigg, 

 of Bristol, larva: of Rosterstammia erxlebella, a genus of which 

 the larva had hitherto been unknown. — Miss Ormerod read a 

 paper entitled " Sugar-cane Borers of British Guiana," and exhi- 

 bit ed specimens of the insects referred to, in different stages of 

 development. The exhibition was made on behalf of the 

 Colonial Company, who were anxious to receive any information 

 as to available and practical methods of dealing with these in- 

 sects. Mr. Distant stated that the circumstances were almost the 

 same on the sugar estates in the Straits Settlements at Malacca, 

 where burning the infected canes was the usual remedy applied. 

 — Jlr. Swinton communicated a note with reference to the urti- 

 cating properties of the larva of Liparis aurijlua, and a com- 

 munication was also received from Mr. McLachlan on correlation 

 of mutilation in the larva with deformity in the imago, being 

 the substance of a notice by M. Melise on the subject in .the 

 Compte Rendu of the Belgian Entomological Society. 



Vienna 



Imperial Academy of Sciences, June 13.— On two new 



Notodelphyides, with remarks on some features in the organisa- 

 tion of this family, by lierr Kerschner. — On the yearly period of 

 the insect fauna of Austria-Hungary, No. IV., by Herr Fritsch. 

 — On the motion of plates between the electrodes of a H0II2 

 machine, by Herr Doubrava. — On the perfect pentagon, by Herr 

 Kohn. — On the specific viscosity of a liquid and its relation to 

 chemical constitution, hy Prof. Pribram and Dr. Handl.— On the 

 crystaUine form and optical properties of isodulcite, by Prof. 

 Urba. — Determination of the inclination from oscillation of a 

 magnetic bar, by Prof. Pscheidl. — The Ferdinandsbrunn spring 

 at Marienbad in Bohemia, by Prof. Gintl. 



Paris 



Academy of Sciences, August 11. — M. Daubree in the 

 chair. — Experimental researches on the erosive action of highly 

 compressed and highly heated gases, and their application to 

 the history of meteors and bolides, by M. D.aubree. — On the 

 acids generated when the crude acids resulting from the saponi- 

 fication of neutral fats are distilled in a current of super-heated 

 steam, by MM. A. Cahours and Demar9ay. — Reply to M. 

 Berthelot's note on hydrate of chloral, by M. Wurtz.— Onthe 

 generation of electricity by the Rays, by M. Ch. Robin. — On the 

 eclipse of July 19 last, observed at Mar.eilles, by M. J. Janssen. 

 — Second and last observation by M. A. Ledieu, on M. Bouquet 

 de la Grye's paper on atmospheric waves. — M. Palacciano was 

 elected correspondent in the Medical and Surgical Section 

 of the Academy, in place of the late M. Lcbert. — On some 

 properties of quadratic forms, by M. Poincare. — On hydro- 

 dynamical principles and the application of these principles, by 

 ^I. G. Clire. — On the formation of nitric ether in wine, by M. 

 Romanet du Caillaud. — On the distillation of liquids under the 

 influence of static electricity, by M. D. Gernez. — On Ampere's 

 currents, by M. Treve. — On the vapour densities of some organic 

 substances with high boiling points, by M. L. Troost. — On the 

 density of chlorine at high temperatures, by M. Ad. Lieben. — On 

 the synthesis of phenol glucoside, and of ortho-formylglucoside or 

 helicine, by M. A. Michael. — On a combination of chromic acid 

 with fluoride of potassium, by M. L. Varenne. — On the produc- 

 tion of crystallised metallic oxides by means of cyanide of 

 potassium, by the same. — On the identity of hydrate of diisoprene 

 and of caoutchine with terj ene. — On the conservation of green 

 fodder, by M. G. Lechartier. — On the latent irrit.-'.lion of the 

 muscle ir. frogs and in man, both in the healthy and the 

 diseased states, by M. M. Mendelssohn. — On the electric 

 irritation of the apex of the heart, by MM. Dastre and 

 Morat.— On the action of the poison from Bethrops jarara- 

 cnssu, by MM. Couty and de Lacerda. — Causes of the alteration 

 of animal temperature produced by ether, chloral and chloroform, 

 by M. Arloing. — On the structure of the cephalic ganglions of 

 insects, by M. W. Wagner. — On the rot of the vine, by M. A. 

 Millardet.— On the temperature of the month of July, 1879, by 

 M. E. Renou. — On the history of perfect numbers, by M. L. 

 Hugo. 



CONTENTS Page 



Weather Charts for the Northern Hemispheue 35i 



The British Association 3S1 



Inaugural Address cf Prof. G. J. AUman, M. D., LL. D., F. R.S. S. I, 



.-ind E., M.R.I. A., Pres. L.S., President 384 



Section D — Biology— Opening Address b.y Prof. St. George Mivart, 

 F.R.S., V.P.Z.S., Sec. L.S., President of the Section .... 393 



Notes 400 



Our AsTRONO.MicAL Colu.mn: — 



The Elongated Nebulae 402 



The New Binary Star t Cygni 4^2 



Letters to the Editor : — 



" Report of an Unusual PI'.c n mencn Observed at Sea." — Edward 



H. Pringle (.mih Bias .uiis) 402 



The Planet Jupiter.— John iURMiNGHAM 403 



Twenty-nine Gleams of Sun '.line, August 7, 8, 9, in Nine Hours.— 



J. F. Campbell (/FjV/iZ'M^raJK) 403 



Electric Clocks.- W. W. Flinders Petrie 4°4 



Did Flowers Exist during the Carboniferous Epoch!— Williaji 



Morris 404 



" Euclid and His Modern Rivals."— The Writer of the Notice 



OF "Euclid AND His Modern Rivals" 404 



Societies and Academies 4^4 



