Dec. 1, 1885.] 



♦ KNO\A/LEDGE ♦ 



69 



led to notice in following out this plan, has been the 

 necessity, for .scientifie and philosophical writing if not 

 for nariMtive, of a point which would sea-ve as (and might 

 b? called) a half-comma. 



* * * 



Mr attention has been called to a suggested method of 

 measuring the sun's distance, depending on determining 

 the titne^ when the moon is half-full before and after 

 "full." Theoretically thi,s method is excellent — (it is 

 practically the same which was suggested by Aristarchus 

 of Samos, as described in n\y book on " The Sun "). The 

 r.ro traversed bj' the moon from half before "full" to 

 half after "full" is greater by about 18' than the arc 

 traversed from half after " full " to hvM before " full " ; 

 for the moon's orbit round the earth (not that she really 

 travels round the earth) subtends about 18' as supposed 

 to be seen from the sun. In re.ility, the application of 

 the method efl'ectivelj', requires that the observer should 

 not only detect but measure accurately within at least 

 one south part, the interval of time between the moment 

 when the moon is really half full, and the moment when 

 the sun and moon are 90^ apart on the celestial sphere, 

 this interval being the time occupied by the moon in 

 traversing 9' or one 2,400th part of her apparent orbit 

 round the earth. This would be about 18 minutes of 

 time, a,nd certainly no one who has ever studied the half 

 moon with a telescope would hope to tell within 18 

 mintites the moment when, taking fair account of her 

 inequalities, she might be regarded as h;',lf full. But to 

 get the sun's distmce otit of this method, with accuracy 

 equalling that already obtained by other methods, the 

 obstrver would have to determine the moment of true 

 half moon within less than four seconds ! 



Reaiung the last paragraph, I feel that an apology 

 is due to those who are enthusiastic about the dignity of 

 science, for my omission of the sweet word " dichotomy " 

 and its cheerful derivatives. I hasten to make them happy 

 by explaining what I really mean — viz., that no reliance 

 c^.n be placed on the method suggested bj- Aristarchus for 

 determining the mean equatorial horizontal solar parallax 

 by chronometric observation of the lunar dichotomy. 



I AM glad to b? able to announce that the change from 

 weekly to monthly Knowledge has apparently met with 

 general approval and has at any rate begun most favour- 

 ably. Many regret the weeklj" ; but their regrets have 

 been expressed in the kindliest way, and always with 

 promise of support to the monthly. 



* * * 



We propose soon to begin a series of studies of 

 Shakespearean Characters, by a Student of Shakespeare, 

 each character being made the subject of a single article. 



i^rlu iSookij to ht JUati— ant> 2.2;11)p. 



The BictionrLrij of National Biojraphy. Edited by 

 Leslie Stephen. Vol. IV. Beal-Biber. (London : 

 Smith, Elder, & Co. 1885.)— Because it i; the fullest, 

 most accurate, and most complete compendium of British 

 Biography extant ; including such diver.*e lives as those 

 of Edmond Beales, of Hyde Park railways notoriety ; 

 Aphra Behn, Cardinal Beaufort, Sir Henry de \\ Beche 



Bewick, the wood-engraver ; and Bishop Berkeley, amid 

 a whole host of others. 



A Short History of the Netherlands. By Alex, yo^^•|■;. 

 (London : T. Fisher Unwin. 1886.) — Because, without 

 going into the detail, or in any legitimate sense attempt- 

 ing to rival Motley's imperishable work, Mr. Young gives 

 a trustworthy and scholarly history of the Netherlands 

 in a compact and readable form. 



History of Astronomij During the Nineteenth Cinfttri/. 

 By Agses M. Cleeke. (Edinburgh : Adam &, Charles 

 Blr,ck. 1885.) — Because, although guilty of the ques- 

 tionable taste of conspicuously puffing a notorious self- 

 advertising "astronomer,'' the authoress has, on the 

 whole, given us a fair and pleasantly-written record of 

 the progress of asti'onomy during the last eighty or ninety 

 years. 



Horse and Man. By the Rev. J. G. Wood. (London : 

 Longmans. Green, lir Co. 1885.) — Because it contains a 

 mass of information of the highest value to every man 

 who keeps a horse either for pleasure or profit. Owners 

 of carriage horses who use — or whose servants use — the 

 wicked " gag " bearing-rein, should study Mr. Wood's 

 text and its illustx-ations. 



Wanderings of Plants and Animals. By Victor Hehn. 

 Edited by J. S. Stallybeass. (London : Swan Sonnen- 

 schein <& Co. 1885.) — Because, though diffuse, it con- 

 tains a great deal of information on the original habitats of 

 animals and vegetables now very widely removed from 

 them. 



Fann Lice-stoch of Great Britain. By Robert Wallace. 

 (Edinburgh: Oliver <t Boyd. 1885.) — Because the F.gri- 

 culturist will find much that is of value to him in con- 

 nection with the management of the solitary element in 

 farming which at present affords the slightest chance of 

 remuneration. 



That Terij Mah. (London : Longmans, Green, & Co. 

 1885.) — Because it is a [very witty and amusing satire 

 upon contemporary crazes ; characterised bv much of 

 Swift's trenchant keenness, while wholly devoid of his 

 coarseness. . 



Hugh's Sacrifice. By Cecil Maeetat Norris — Through 

 a Befiner's Fire. By Eleaxoe Holmes — A Generous Friend- 

 ship — Girlhood's l)ays — Master of his Fate. By A. Blanche 

 — The Baisij (London : Griffith, Farran, it Co.) — When I 

 was a Child. By LiSDA Villaei (London : T. Fisher 

 Unwin) — Prudence Winterburn. By Saeah Doudney 

 (London : Hodder it Stoughton) — Because, if not reaching 

 the highest level of fiction, they are all sound, healthy 

 stories for the young, containing good morals, and are, in 

 more than one case, decidedly interesting. 



From the Tanyard to the White House. By Wm. M. 

 TuAYEE. (London: Hodder it Stoughton.) — Because it 

 contains a biography of General Grant which will 

 interest boys (though we earnestly wish that Mr. Thayer 

 would never try to be funny). 



Queer Pets. By Olive Thorne Millee. (London: 

 Griffith, Farran, & Co.) — Because it puts natural history 

 in an attractive and amusing light for children, who are 

 never cruel to their own actual pets. 



The Missing Man. By H. Sutherland - Edwards. 

 (Remington it Co. 1885.) — Because it is a novel of 

 mirch more thau ordinary interest. Belonging to the 

 new school of cheap sensation novels inaugurated by 

 Hugh Conway, it is nevertheless a work written with 

 great care, so that the uncomfortable feeling of impro- 



