240 



NATURE 



[July 4, 1889 



data hitherto accepted by various authorities require to be modi- 

 fied. He finds the mean elevation of all the continents above 

 sea-level to be 693 metres : northern hemisphere, 713 ; southern 

 hemisphere, 634; Europe, 317; Asia, 957; Africa, 612; 

 North America, 622 ; South America, 617 ; Australia, 240. 

 Mean depths of all the oceans, 3803 : Pacific, 4380 ; Atlantic, 

 4022 ; Indian, 3674 ; northern seas, 3627 ; southern seas, 

 3927- 



Berlin. 



Physical Society, June 7. — Prof, von Helmholtz, President, 

 in the chair. — Dr. R. von Helmholtz communicated the results 

 •of his experiments on the radiating power of flames. The problem 

 which he had set before himself was to determine the relationship 

 between the radiant energy of flames, and the amount of gas 

 consumed for their production. The latter was measured by the 

 fall of the gasometer-globe which contained the gas, the former 

 by means of a bolometer, for each of whose scale-divisions the 

 equivalent value in heat-units had been carefully determined by 

 three different methods. The radiating energy of the flames 

 depended upon a number of conditions which were each severally 

 investigated ; as, for instance, the size and shape of the flames, the 

 amount of foreign gases introduced, and the ratio of the amount 

 of oxygen to the amount of gases with which it was mixed. 

 For the purposes of comparative measurements, a moderately 

 high flame was chosen, which produced no smoke and was 6 mm. 

 thick. Luminous flames radiated more energy than non-luminous, 

 and it was proved by an extended series of careful quantitative 

 experiments that the radiating power of the flames was not 

 dependent upon their temperature. From this it follows that 

 Kirchoffs law does not hold good for flames — a result which is, 

 however, quite in accordance with the limitations he put to his law 

 for those cases in which heat is directly converted into radiating 

 energy. In the case of flames it must be borne in mind that 

 chemical affinity comes additionally into play : the speaker 

 entered fully into the influence of this upon the radiation of 

 energy, and endeavoured to make it clear by means of an ex- 

 tremely interesting hypothesis. After this he stated the numerical 

 data which he had obtained for both luminous and non luminous 

 flames, produced with a series of gases — hydrogen, carbonicoxide, 

 methane, coal-gas, methyl-alcohol, &c. Starting as a basis with 

 Julius's statement that the products of combustion are the only 

 criteria of the amount of radiation, and hence calculating the 

 radiating energy of the flames, he obtained values which 

 corresponded very closely in most cases with those actually 

 observed. Finally he calculated the total useful effect which 

 can be obtained as radiant energy from the gases which are 

 being consumed in the production of the flame. From this he 

 arrived at the interesting result that it is far more economical 

 to use the gases for driving a dynamo which supplies incan- 

 descent lamps, and to utilize the energy radiated from the latter, 

 than to burn the gases, and utilize the energy which is radiated 

 out from their non-luminous flames. The communication, as a 

 whole, of which only a short sketch has here been given, 

 contained a large number of very valuable quantitative results. 

 — Dr. Budde spoke on " tautological " contacts in mechanics, and 

 deduced the general conditions under which a close determination 

 of contacts between surfaces and points is unnecessary ("tauto- 

 logical "). 



Physiological Society, June 14. — Prof. Munk, President, 

 in the chair. — Dr. Openchowski spoke on the researches which 

 he has carried on since 1883 on the movement and innervation 

 ■of the stomach. The movements were recorded by introducing 

 into the stomach a small bag filled with water and connected 

 with a manometer, the motion of the column of fluid in the latter 

 being recorded graphically. The fundus and first third of the 

 stomach never exhibit any spontaneous peristaltic movements, 

 these being confined to the second and last third, including the 

 pylorus. The centre for the initiation of the motor movements 

 lies in the ganglion cells under the serous coat which extend all 

 over the stomach along the branches of the vagus nerve. The 

 motor and inhibitory centres on which the movements of the 

 cardiac end depend are situated in the brain and spinal cord ; 

 the motor centres lie in the corpora quadrigemina and in the 

 spinal cord between the fifth and eighth thoracic vertebrae ; the 

 inhibitory centres lie in the corpus striatum, and a few are scat- 

 tered in the spinal cord. The connection between the cranial 

 centres and the stomach is provided by the vagi ; there is no 

 connection between the cranial and spinal centres. The centres 

 for the pyloric end are situated in the same places as those for 



the cardiac end, but the centres which are inhibitory for the 

 latter are motor for the former, and vice versa. The speaker 

 has studied the act of vomiting very fully. The stomach plays 

 an active part in this act. After paralysis of the stomach, the 

 movements of vomiting may be brought about, but do not lead 

 to an ejection of the stomach's contents. After adminis- 

 tering an emetic, such as sulphate of copper, the fundus and 

 first third of the stomach is actively dilated ; the pylorus is at 

 the same time relaxed, and the contents of the small intestine are 

 driven into the stomach by the contraction of the intestinal walls, 

 and then, by the strong and progressive contractions of the last 

 two-thirds of the stomach, they are driven on into the first third 

 of the stomach. At this stage the stomach has a pear-like shape, 

 the fundus being unduly distended. The reflex movements of 

 vomiting now occur, and the pressure exerted by the abdominal 

 muscles leads to the emptying of the highly distended fundus. 

 As after paralysis of the stomach, so also after section of the 

 vagi and excision of the stomach and intestines, the movements 

 of vomiting occur when an emetic is administered. No single 

 centre for vomiting appears to exist and be actively functional 

 during the act, but there would seem rather to be a combination 

 of co-ordinated centres, whose position has still to be more 

 definitelv ascertained. 



BOOKS, PAMPHLETS, and SERIALS RECEIVED. 



U.S. Commission of Fish and Fisheries, 4 vols. : G. Brown Goode.— In- 

 organic Chemistry: Ira Remsen (Macmillan). — Eclipses and Transits in 

 Future Years: S. J. Johnson (Parker).— Fundamental Problems: Paul 

 Carus (Open Court Publishing Company). — Rendiconti del Circulo Mate- 

 matico (Palermo). — Avifauna Italica, parte prima : E. H. Giglioli (Mon- 

 nier, Florence). — Injurious Farm and Fruit Insects of South Africa : E. A. 

 Ormerod(Simpkin).— Gaseous Fuel: B. H. Thwaite (Whittaker).— Electri- 

 city : A. Rust (Spon). — American Resorts : B. W. James (Davis). — The Pro- 

 spector's Hand-book, 4th edition : J. W. Anderson (Lockwood).—/'/^or-w/«w 

 tenax as a Fibrous Plant, 2nd edition : edited by Sir J. Hector (Wellington, 

 New Zealand). — Geology in Systematic Notes and Tables, 2nd edition : W. 

 F. Cjwinnei; (Allman). — Kant's Critical Philosophy, vol ii. The Prolegomena ; 

 translated : J. P. Mahaffy and J. H. Bernard (Macmillan).— Physics of the 

 Earth's Crust. 2nd edition : Rev. O. Fisher (Macmillan).— Schriften der 

 Naturforschenden Gesellschaft in Danzig ; Neue Folge, Siebenten Bandes, 

 Zweites Heft (Danzig).— Observations made at the Blue Hill Meteorological 

 Observatory, Mass., U.S.A., 1S87 : A. L. Rotch (Camb., Ma.ss.).— Trans- 

 actions and Proceedings of the New Zealand Institute, vol. xxi. (Triibner). 



CONTENTS. PAGE 



Cryptogamic Botany 217 



An English Railway 219 



Our Book Shelf:- - 



Schmidt: " Zur Geologic der Schweizeralpen " . . . 220 

 Wagner : " Die Entstehung der Arten durch raum- 



liche Sonderung " 220 



Watson: "Sylvan Folk" 221 



Blanford : " A Practical Guide to the Climates and 

 Weather of India, Ceylon, and Burmah " .... 221 



" The Unrivalled Atlas " 221 



Letters to the Editor : — 



Coral Reefs.— Dr. John Murray; Prof. T. G. 

 Bonney, F.R.S. ; Dr. H. B. Guppy; P. W. 



Bassett-Smith, R.N 222 



Hibernation of Martins in the Argentine Republic. — 



Tommaso Salvador! 223 



Atmospheric Electricity. — Alexander McAdie . . 223 

 Upper Wind Currents over the Equator in the Atlantic 



Ocean. — E. Foulger 224 



Patches of Pri-matic Light. — C.S.Scott 224 



A Chimpanzee's Humour. — Harold Picton .... 224 

 Prof. Huxley and M. Pasteur on Hydrophobia ... 22 



An Index to Science. By J. Taylor Kay 



Iridescent Crystals. {Illustrated.) By Lord Rayleigh, 



F.R.S 



Notes 



Our Astronomical Column : — 



Astronomical Society of the Pacific 



A New Comet 



Astronomical Phenomena for the Week 1889 



July 7-13 



Optical Torque. I. {Illustrated.) By Prof. Silvanus 



P. Thompson 



The Planet Uranus. By R. A. Gregory 



Babylonian Astronomy. I. By G. Bertin 237 



University and Educational Intelligence 237) 



Societies and Academies 237! 



Books, Pamphlets, and Serials Received 240J 



