110 



♦ KNOWLEDGE ♦ 



[Feb. 23, 1883. 



member for Mid-Surrey has so usefully co-operated. A 

 few months ago the Director of the Gardens was per- 

 suaded, as the result of their eifoi-ts, to reconsider his 

 proposal to shut up the llichmond entrance -gate, 

 which would have increased the distance to be walked 

 or driven over liy the very numerous \i8itors who 

 reach Kew Gardens by the various railway lines converging 

 at Richmond by some three-quarters of a mile. We 

 trust, however, that Sir Joseph Hooker will not take it 

 amiss if the arrangement which is to come into operation 

 this spring is considered not to be quite satisfactory. 

 Twelve o'clock is a better hour for opening the Gardens than 

 one, but it lias always been contended — and in our view 

 the contention has never been upset — that there is no 

 adequate reason for keeping the gates closed after ten. 

 The visitors would not be numerous enough at 

 that early hour to interfere in any way with the work 

 going on, and the extra cost which might be incurred 

 for police or other attendance would be inappreciable. 

 We believe, however, that all reasonable requirements 

 would be met if the Gardens were opened, except on bank 

 holidays, at eleven o'clock. The gardeners begin their 

 work, when the daylight permits, as early as six in the 

 morning, and they would thus have five hours without 

 any disturbance from visitors. We have no doubt that 

 the twelve o'clock opening will be found to occasion no 

 inconvenience to the Director or his assistants, and we 

 trust, therefore, to the concession of another hour next 

 year. With that, -we believe, everybody will be satisfied. 



The Effect of the Electric Light upon Plants. — 

 M. P. P. Deherain has made a series of interesting expe- 

 riments at the Palais d'Industrie, Paris, and communicated 

 the result to the Annahs Ayronomiques. The author sums 

 up his conclusions thus : — 1. The electric arc light emits 

 radiations which are injurious to vegetation. 2. Most of 

 these radiations are arrested by colourless glass. 3. The 

 electric light emits radiations powerful enough to maintain 

 mature plants in vegetation for two months and a-lialf. 

 4. The beneficial radiations are not sufficiently powerful to 

 cause the growth of germinating seeds, or to allow of the 

 maturation of fruit in older plants. 



Dr. D. E. Salmon, of America, has pursued parallel inves- 

 tigations with those of M. Pasteur, of the microbe of hen 

 cholera, and has conclusively satisfied himself of the accuracy 

 of the results announced by the latter. He regards his 

 researches as demonstrating that the virulent liquids of 

 the fowl's body contain micrococci, that these can be 

 cultivated, and that liquids in which bacteria are culti- 

 vated produce the disease by inoculation. His experiments 

 indicate that the activity of the virus is destroyed at a 

 temperature of 182° Fahr. 



The sea serpent is againj^talked of ; but this time it 

 seems as though the supposed sea monster had been a 

 flight of sea birds. And because an objict a mile or more 

 away, taken for a sea monster, has turned out over and 

 over again to be sea-drift, or a lot of porpoises, or a flight 

 of bii'ds, or distant undulating hills seen indistinctly 

 through disturbed and liazy air, it of course follows 

 that the long-necked creature which the captain and officers 

 of the Ddildiis saw within 200 yards, at a distance at 

 which a friend's face could be recognised, urging its 

 way swiftly against a ten-knot breeze, with the water 

 visibly surging against its neck, was seaweed round a 

 mast, or something of the sort. 



M. Bergeron has produced imitations of the forms of 

 lunar craters, by turning a current of gas into a melted 

 metallic mass at the moment when solidification is about 

 to begin. He obtained exact representations of the different 

 varieties of hollows shown upon the moon, by using different 

 metallic mixtures. 



According to Mr. G. Macloskie, the American elm-leaf 

 beetle hibernates in cellars and attics in countless numbers. 

 Three broods are brought forth in a season. This destruc- 

 tive insect is found only in the Eastern States and parts 

 of New Jersey and Pennsylvania. Poison is the most 

 complete remedy for it — one ponnd of London purple to 

 one hundred gallons of water, squirted up into the tree. 



A Queer Flsii. — The TravaiUevr dredged up from a 

 depth of 2,300 metres (2,.51.'>-35G yards), on the coast of 

 Morocco, a fish, which has been named Eurijpharynx 

 pvhcanoides. To form an idea of it, let two tablespoons, 

 with pointed ends and deep bowls, be held so as to repre- 

 sent a great open mouth. The body and tail thin off 

 rapidly, and may be likened to a slender spoon handle. 

 They are ornamented with pin-like rows of soft spines. 

 The creature is ISiin. long, and the thickest part of its 

 body about 8-10 in. wide. The head, without reckoning 

 the jaws, is short, 3 centimetres (I'lSlin.); the jaws 

 extending nearly 4 in. The mouth opening is enormous. 

 There are five internal gills, with a small external orifice 

 for the escape of the water. The skull is peculiar, the 

 upper jaw being reduced to a thin rod, united to the head 

 and the interior portions of the body by an extensible 

 cutaneous fold. The mouth is capable of pelican-like 

 expansion. It is supposed to form a magazine for food, 

 and that digestion is partially carried on there. The fins 

 are extremely small. Professor Vailliant has described the 

 fish to the Institute. 



The Colour of Water. — M. W. Spring, in a lecture 

 at the University of Li^ge, described his experiments to 

 ascertain the colour of pure water. He referred to the 

 researches of Stas, who found that common spring water, 

 distilled twice over and immediately evaporated in a 

 platina basin, volatilized without leaving any residue ; but 

 if this water were kept for a few days, and then evaporated, 

 it left a perceptible yellowish brown deposit, which at 

 a red heat, in air, could be completely burnt. To obtain 

 water quite free from this matter, Stas' jalan was followed. 

 The water was first boiled for four hours over potash manga- 

 nate and permanganate, and then distilled twice in platina 

 vessels, and the product received in a silver vessel protected 

 from contact with the air. This water, when evaporated 

 from a well-polished capsule of platina, left no stain. 

 In order to obtain the requisite depth of water for tlie 

 light to pass through, and make any colour it would give 

 visible, M. Spring used glass tubes IG ft. long, and rather 

 more than \\ in. wide. The tubes were closed at both 

 ends by glass flats, and furnished with a pipe through 

 which the water could be introduced. When pure water 

 was placed in these tubes and white light sent through it, 

 the colour " was of a blue of which it is difficult to repre- 

 sent the purity ; the finest blue on a tine day in a 

 mountain region, above the grosser emanations of the soil, 

 can alone be compared with it." No change occurred 

 when the water was kept in the tubes for several weeks. 

 The addition of a little lime-water, which appeared quite 

 limpid, entirely stopped the passage of the light, "as if ink 

 had been put in." The lecture is i-eported fully in 

 llevue Scieulijlque Feb. 10, 1883. 



