P OP ULAR MIS CELL ANY. 



119 



Oa each side is a broadside port through 

 which Whitehead torpedoes may be launched. 

 The after-part below is fitted up as a tor- 

 pedo workshop. The hull is divided into a 

 number of water-tight compartments, not 

 connected, as is the usual mode, with water- 

 tight doors, entrance being gained from the 

 upper and main decks. The element of 

 danger resulting from leaving the connec- 

 tions open in certain eventualities is thus 

 obviated, though it is calculated that the 

 filling of one or two of the compartments 

 with water would not materially affect the 

 behavior of the ship. She is to carry six 

 second-class torpedo-boats. Four of these 

 boats will be amidships, the chocks on which 

 they rest running on a tramway. She will 

 also carry a 42-feet steam launcli and a 37- 

 feet steam pinnace. . The Hecla will be pro- 

 vided with booms and nets to protect her 

 from an enemy's torpedoes — the booms, 

 when not in use, lying fore and aft against 

 the side of the ship. 



Women and the Study of Science.— Tlie 



medical profession in England appears to be 

 seriously alarmed at the prospect of an in- 

 vasion of its ranks by womankind. Scien- 

 tific workers need have no such fears of 

 their peculiar field being occupied by the 

 gentler sex, if the " Cambridge Higher Local 

 Examinations," lately held, are any index 

 of the disposition of women-students in Eng- 

 land toward scientific studies : only about 

 thirty out of five hundred female students, 

 we are informed by Nature, took the science 

 subjects ; twenty-one took botany, one failed, 

 and three obtained distinction ; twenty-six ge- 

 ology and physical geography, of whom two 

 failed, and seven were distinguished ; sev- 

 en geology, one failed, three distinguished ; 

 nine chemistry, three failed, none distin- 

 guished. Ten of the science candidates sat 

 at Cambridge, and among them they gained 

 ten out of fourteen of the distinctions given. 

 Miss E. M. Clarke, of Cambridge, was dis- 

 tinguished in geology, zoology, and botany, 

 and passed in chemistry. Mathematics got 

 only twenty-three candidates, of whom four 

 failed ; only two, however, were placed in 

 the first class (being Cambridge students), 

 and two in the second. We are glad to 

 learn that two new subjects are to be set in 

 the saience group next year, namely, physics 



and physiology, the latter so much needed 

 in all girls' schools. Also, students will be 

 allowed to take this group without having 

 to pass Group A (literature and history) 

 first, although it will be required for a full 

 certificate. 



Sir Wyville Thomson on Deep - Sea 

 Soundings.— Sir Wyville Thomson, as Pres- 

 ident of the Geographical Section of the 

 British Association, delivered an address, at 

 the Dublin meeting of that body, on the re- 

 sults of recent deep-sea sounding. He dwelt 

 particularly on the facts of ocean circulation 

 as developed by the Challenger Expedition. 

 All recent observations, he said, have shown 

 that the vast expanse of water which has its 

 centre in the southei-n hemisphere is the 

 one great ocean of the world, and the At- 

 lantic with the Arctic Sea, and the JS'orth 

 Pacific, are merely its northward-extending 

 gulfs : any physical phenomena atfectmg ob- 

 viously one portion of its area must be re- 

 garded as one- of an interdependent system 

 of phenomena afiecting the ocean as a whole. 

 Shallow as the stratum of water forming the 

 ocean is — a mere film in proportion to the 

 radius of the earth — it is very definitely split 

 up into two layers, which, so far as all ques- 

 tions regarding ocean-movements are con- 

 cerned, are under very difierent conditions. 

 At a depth varying in different parts of the 

 world, but averaging perhaps five hundred 

 fathoms, there exists a layer of water at a 

 temperature of 40" Fahr., which may be re- 

 garded as a sort of neutral band separating 

 the two layers. Above this band the tem- 

 perature varies greatly over different areas, 

 the isothermobathic lines being sometimes 

 tolerably equally distributed, and at other 

 times crowding together toward the surface, 

 while beneath it the temperature almost 

 universally sinks very slowly and with in- 

 creasing slowness to a minimum at the bot- 

 tom. With some reservation it may be af- 

 firmed that the trade-winds and their modi- 

 fications and counter-currents are the cause 

 of all movements in the stratum of the ocean 

 above the neutral layer. All the vast mass 

 of water, often upward of two thousand 

 fathoms in thickness below the neutral 

 band, is moving slowly to the northward ; 

 in fact, the depths of the Atlantic, the Pacific, 

 and the Indian Ocean, are occupied by 



