Auo. 17, 1883.] 



♦ KNOWLEDGE ♦ 



109 



THE FACE OF THE SKY. 



Fkom August 17 to August 31. 

 By F.R.A.S. 



THE recent exhibition of increased activity on the surface of the 

 sun will, of course, prompt the student to keep a sedulous 

 watch upon the solar disc for its consequent phenomena. Such a 

 spectacle as that described by Mr. Slack (p. 70) will afford an 

 ample reward for any amount of watching. The night sky will be 

 found delineated on Map VIII. of " The Stars in their Seasons." 

 Mercury is but indifferently placed for the observer, but may just 

 possibly be caught on a very clear evening after sunset, close to 

 the horizon and a little to th.e south of west. Venus remains, for 

 our present purpose, invisible ; as do Uranus and Neptune. Mars 

 rises before midnight, almost in the north-east. His telescopic 

 diameter is too small to enable the observer to examine his surface. 

 He still presents the appearance of a blazing red star, and is 

 situated to the north-east of f Tauri (" The Stars in their Seasons," 

 Map I.). Jupiter has not yet come into sight. Saturn rises, of 

 course, sooner and sooner every night, appearing above the north- 

 east by east point of the horizon about 10 p.m. at the end of 

 August. Hence, by midnight, he will be some 18° high, and fairly 

 well observable. He is moving slowly to the eastward in that void 

 part of the sky north-east of * Geminoruni (ilap I.). The moon is 

 14'4 days old at noou to-day, and, quite obviously, 28'4 days old at 

 the same hour on the 3lst. Hence, after about the 25th 

 she will be but poorly placed for the observer during the working 

 hours of the night. Two occultations of stars will occur during 

 the fourteen days covered by these notes. The first will happen 

 on the 21st, when the 4th magnitude star e Piscium will disappear 

 at the moon's bright limb at 12 h. 20 m. p.m. at an angle from her 

 vertex of 155°, and reappear from behind her dark lirub at 12 h. 

 42 m. p.m. at an angle of 197° from her vertex. The second 

 occultation will be that of the 6th magnitude star B. A. C. 1206, 

 which, on the night of the 24th, will disappear at the moon's 

 bright limb at 10 h. 30 m. at an angle of 73° from her vertex ; 

 re-appearing at her dark limb at a vertical angle of 235° at 

 11 h. 21 m. p.m. During the -whole of to-day and to-morrow, 

 and, in fact, until 6 p.m. on Sunday, the 19th, the moon 

 will be travelling through Aquarius, from which constellation, at 

 the hour named, she will pass into Pisces. She will not quit Pisces 

 until 9 p.m. on the 22nd, when she will travel into Aries. She will 

 occupy until 1 p.m. on the 24th in crossing Aries, and will enter 

 Taurus between 1 and 2 o'clock on the afternoon of the latter day. She 

 continues in Taurus until 1 a.m. on the 27th, when she begins to cross 

 the northern part of Orion. This occupies her until 2 p.m. on the 

 same day. She then emerges in Gemini, and remains in that 

 constellation until 7 a.m. on the 28th, at which hour she enters 

 Cancer. It will be 11 o'clock at night on the 30th before she 

 reaches Leo. There she continues until 10 p.m. on the 31st, when 

 she descends into Sextans. We there leave her. 



In 1871 tlio total population of the seven Australasian 

 colonies — which include the five Australian colonies, viz., 

 Victoria, New South Wales, Queensland, South Australia, 

 and West Australia, and the colonies of Tasmania and 

 New Zealand — was only 1,978,7-tO. In 1881 the total 

 population was 2,83.">,954, showing an increase in ten years 

 of 8.^7,206, or an average of S^u per cent. Ten years 

 ago the combined exports of the same colonics amounted to 

 approximately .£07,000,000, and in 18S1 to £10."),000,000, 

 showing an advance of more than 50 per cent. This is 

 equal to about .£38 per head of population. The public 

 revenue of the seven colonies during the year 1881 

 amounted to about £21,000,000, against .£18,000,000 in 

 1880, being an increase of £3,000,000. The colonies 

 possess .''),426 miles of railway, 49,10.'') miles of telegraph, 

 78,000,000 sheep — the wool clip of wliich last year realised 

 the sum of about £21,000,000— besides 8,091,910 cattle, 

 and several millions of horses and pigs. During the year 

 18S1, 10,090 vessels, of an aggregate tonnage of 9,.">04,130, 

 touched at the various ports of the colonies. The same 

 colonies have 7,017,380 acres of land under profitable 

 cultivation, and produce annually about 30,000,000 bushels 

 of wheat, and 11,717,819 bushels of oats. Of these latter 

 New Zealand alone produces 0,924,8-18 bushels. 



TO 



" Let Knowledge grow from more to more." — Alfred Tennyson. 



Only a small proportion of Letters received can possihly he in- 

 serted. Correspondents must not he offended, therefore, should their 

 letters not appear. 



All Editorial communications should he addressed to the Editoe of 

 K.vowLEDGE ; all Business communications to the Publishers, at the 

 Office, 74, Great Queen-street, W.C. If this is not attended to 



DELAT.S ARISE FOR WHICH THE EDITOR IS NOT RESPONSIBLE. 



All Remittances, Cheques, and Post Office Orders should he made 

 payable to Messrs. Wyman & Sons. 



The Editor is not responsible for the opinions of correspondents. 



No COMMUNICATIONS ARE ANSWERED BY POST, EVEN THOUGH STAMPED 

 AND DIRECTED ENVELOPE BE ENCLOSED. 



PRESCRIBING FOR CHOLERA. 



[896] — With reference to the letter appearing on page 60 of 

 Knowledge, July 27, 1883, headed "Cholera" (preventive), I wish 

 to make a few remarks. 



In the first place, the reverend gentleman should have defined 

 cholera as he understands it and prescribes for it. Judging by the 

 tenour of the letter, he draws no distinction between cholera and 

 diarrhcea in its severer forms. Now, it is hardly necessary to say 

 that a primary essential to correct and rational treatment is to 

 understand what disease has to be dealt with. 



Again, filtration of water is not sufficient; it is necessary to boil 

 it and preserve from absorbing impurities present in the atmo- 

 sphere, whieh it will do readily on cooling. It cannot be too clearly 

 understood that no prescription is indiscriminately applicable to 

 several cases. In diarrhoea, pre-eminently, the treatment of a 

 given case will depend upon its cause, and the sooner the doctor 

 sees the case the better. It is folly to trifle away time that may 

 be of vital importance. Why the crudely and imperfectly tran- 

 scribed prescription should be called an " Indian remedy " I cannot 

 imagine— nor can I imagine how an educated man can so lack in 

 ordinary etiquette as to publish the result of other men's labours 

 without attempting to acknowledge whence the information was 

 derived. I take this opportunity to draw attention, through the 

 columns of your journal, to the obvious irregularity of a clergyman 

 taking upon himself to prescribe — unfortunately, of not infrequent 

 occurrence. Surely a very recent example should prove a warning. 



A Reader. 



[We agree with " A Reader," that there is an objection to pub- 

 lishing prescriptions in such organs as Knowledge, Health, &c., 

 even though such prescriptions may have high medical authority in 

 their favour. The prescriptions may be good bat their application 

 may be bad. " Won't do so any more."- — R. P.] 



GIRTH AND THE PARCEL POST. 



[897] — It may be useful in view of the coming operations of the 

 Parcel Post to inquire minutely into the restrictions which the 

 authorities impose upon the size of the parcels that may be sent. 

 These are — Maximum length, 3 ft. 6 in. ; maximum length and girth 

 combined, 6 ft. 



The first presents no difficulty. A parcel has of necessity, like 

 any other solid body, length, breadth, and thickness — i.e, it has three 

 dimensions. The above restriction simply requires the greatest 

 dimension to be less than 3 ft. 6 in. 



When we come to the second restriction we are met by the word 

 "girth." Now girth is a good old Saxon word, and is connected 

 with girdle. The scientific idea presented to the ordinary feminine 

 mind is " how much round the waist ? " — unless, indeed, the answer 

 come from a Girt(h)onite, and then something very precise may be 

 expected. 



The word girth may bo parajihrased cii-cumference or perimeter. 

 The old nmthcmatical term is periphery. Imagine a solid cylindrical 

 pillar of circular section, such as may be seen in many churches 

 and cathedrals. Suppose it were required to calculate the number 

 of cubic feet in such a pillar the height of which was known. A 

 string ]>asscd round wonld give the girth, say 10ft. Since the cir- 

 cumference of a circle is three and one-seventh times its diameter, 

 this would give the diameter about 3 ft. 2 in. Whence the area of 



