282 



♦ KNOWLEDGE ♦ 



[May 11, 1883. 



cli^sirpfl extent, but not sufficient to distress the patient. 

 1'Iic pointer on the rheostat Vieing turned slowly, the metal 

 lilind is drawn (at J.), and the ohserver has the field 

 liefore liini. 



By tlie curve in tlie tube not only is the introduction of 

 the instrument facilitated — it having been found impossible 

 to pass a perfectly straight tube so far as is necessary for 

 this purpose — but it will be seen that, witli partial rotation 

 of the tube about the long axis of the straight portion, the 

 extremity carrying the window and the light makes quite 

 an excursion, and permits the view of a much more 

 extensive surface than would be possible were no such 

 excursion made. 



^Moreover, as it is provided with an optical system, it 

 obtains, tliat as the instrument is rotated toward a given 

 point of the mucous membrane its image is enlarged ; while 

 as it is further removed the image is diminished, while the 

 field is enlarged. At a distance of two centimetres the 

 image is of natural size. The " definition " of this system 

 is excellent, and granted a tolerance of the instrument on 

 the patient's part, and the requisite skill on that of the 

 observer, a very satisfactory examination can be made. 



A variety of other instruments are made, which are 

 operated suljstantially in the same general maimer as the 

 one described. For example, we have the laryngoscope, 

 for examination of all parts of the throat ; the cesophago- 

 scope, for the gullet ; the otoscope, for the ears ; the 

 urethroscope, for the bladder ; the cystoscope, ifec. The 

 invention of instruments marks another step in electrical 

 progress. They promise to be of utility and importance to 

 the medical profession, for by their use many parts of the 

 human system heretofore hidden from the eye may now l)e 

 brilliantly lighted and examined, and their condition in 

 disease and health ascertained. — Scientific American. 



THE FACE OF THE SKY. 



Fkom May 11 to M.iY 25. 



By F.R.A.S. 



TILE student will, as usual, watch the Sun daily for spots and 

 faculaj. Map V. of " The Stars in their Seasons " will show 

 the aspect of the night sky durinj^ our specified period. Prom 

 May 22 to July 30 thei'e will be no real night in England ; twilight 

 existing from sunset to suni-ise. Mercury is still visible after 

 sunset, towards the W.N.W. part of the horizon. On the 22nd, 23rd, 

 and 2-lth he will bo below /3 Tauri. For the purpose of those for 

 whom these notes are intended, the rest of the planets, save 

 Uranus, are now visible. Uranus himself is sensibly stationary 

 above r Lconis. He must bo looked for directly it is dark enough. 



There will be two occultations of stars by the moon on the night 

 of the 17th. The first is that of x A^irginis, of the 5th magnitude, 

 which will disapjiear at the moon's dark limb at 9 h. 27 m. at an 

 angle of 79° from her vertex, reappearing at her bright limb at a 

 vertical angle of 258" at 10 h. 48 m. The second is an occultation 

 of I! A C 4259, a Cth magnitude star, which will disappear at the 

 dark limb at 9h. 34m. at an angle from the moon's vertex of 76°, 

 to reappear at her bright limb at an angle of 263° from her vertex 

 at lull. 56 m. The moon's ago at noon to-day (the 11th) is 46 days; 

 and on the 25th it will obvionsly bo 1826 days. Hence it will be 

 seen that up to about the 20th she will be in the most favourable 

 phase for the observer. During the next twenty-four hours she 

 will travel from (Jemini into Cancer, where she will remain 

 during the 12th. Sho will leave Cancer and enter Leo on tho 

 13th. She will bo crossing Sextans during a good deal of the 14th, 

 bnt will return into Iico before noon on tho 15th, and remain in 

 that constellation during tho whole of the succeeding twenty-four 

 hours. During tho afternoon of the 16th she will travel into 

 Virgo, where sho will remain during the during tho 17th, 18th, and 

 part of the 19th, passing into Libra during the early morning of 

 tho 20th, and continuing there for tho succeeding four-and-twenty 

 hours. She moves into Scorpio about one a.m. on the 22nd. In 

 tho early afternoon of that day her path carries her into Ophiu- 

 chus, where we still find her up to seven a.m. on tho 23rd. Then 

 she |in.sses into Sagittarius, where sho remains during tho 24th and 

 25tli, and where wo leave her. 



ilcbich)£(. 



SNAKE POISONS.* 

 i MONG the mysteries which science presents to us for 

 1\. investigation, there are few stranger or more alluring 

 than those associated with snakes of the poisonous varieties. 

 To begin with, the very e.xistence of this singular provision 

 — the power of poisoning — is a mystery of the strangest 

 kind, at least to those who adopt the view of special 

 creation for each class of animate existence. Why should 

 certain creatures be provided with a power of killing other 

 animals than those which are their natural prey ? The 

 Daboia and the Cobra, the Rattlesnake of America and 

 the Blacksnake of Australia, do not require for their food 

 such animals as dogs, and pigs, and monkeys, still less 

 can they prey on man. Yet are they provided with 

 the means of killing these animals, and that not in 

 self-defence, for so far is the power of poisoning from pro- 

 tecting these animals that it serves as the most effective 

 means of bringing upon them the destructive powers of 

 man, the most potent of their enemies. To the believer in 

 evolution, indeed, it is tolerably clear how this poisonous 

 attribute was obtained. He can see, for instance, that 

 without it the cobra could hardly secure its natural prey 

 — creatures so lively, that, if merely caught and swallowed, 

 their activity and tenacity of life would cause them to be 

 most uncomfortable occupants of their capturer's stomach ; 

 whereas the paralysing venom speedily reduces them to a 

 motionless state, " and places them," as Dr. Wall puts it, 

 " at the mercy of the gastric arrangements of their enemy." 

 The daboia, again, is in its movable poison fangs provided 

 with " an elaborate hunting weapon," as truly such as 

 the sportsman's gun. There is also, as Dr. Wall says, 

 " a refinement about the physiological contrivance that 

 can either kill at once by convulsions, or after an interi^al 

 by paralysis, or at a still more remote period by blood- 

 poisoning " (this relates specially to viperine poisoning), 

 " to which the mechanical appliance " — the gun — -" fails 

 utterly to attain." 



Dr. Wall's book gives a most interesting and detailed 

 account of snake poisoning, indicating the phenomena 

 which characterise the progress of colubrine and viperine 

 poisoning. It will astonish many to learn that the deadly 

 rattlesnake of America — a viper — is far less deadly than 

 the colubrine snakes. The average period before death in 

 four fatal cases of Crotalus poisoning in dogs was 2 hrs. 

 2G min. ; and no fewer than five dogs recovered completely 

 after being bitten : whereas with the Indian Cobra, " the 

 average length of the period of fatal poisoning was 34-4 

 minutes," and with the Australian Hoplocephalus (a 

 coluber) it was 1 hr. 24 min. ; so that the rattlesnake 

 is much less dangerous than either the Cobra or the 

 Hoplocephalus. 



As to remedial measures, it is rather disheartening to 

 find that " the more frequent is the administration of anti- 

 dotes, the shorter is the duration of life after it." In 

 colubrine poisoning the patient should have nothing given 

 him to swallow, after salivation and paralysis of the tongue 

 and throat have shown themselves, as he is quite incapable 

 of taking anything into the stomach, and the substance will 

 very likely be forced into the windpipe. " I have even 

 found, after death," says Dr. Wall, " remedies in the air- 

 tubes of the lungs, which had been forced there by 

 anxious friends, a circumstance which would have rendered 

 recovery impossible." 



* '* Indian Snake Poisons, their Nature and Effects." Bv A. J. 

 Wall, M.D. Lond., ll.R.C.S., &c. (W. H. Allen & Co., London, 

 1883.) 



