211. 



• KNOWLEDGE • 



[Apkil 27, 1883. 



Although tlirco months will pass lioforo the Engineering,' 

 and Metal Trades E.\liiI>ition will bo held, the preparations 

 for it are very advanced, and the principal dilliculty of the 

 promoter, Mr. Samson Harnett, will probably be that of 

 finding sufficient space for exhibitors within the narrow 

 limits of the Agricultural Hall, as already over 200 appli- 

 cations for space have liecn accepted. At present the 

 space has been let almost exclusively to manufacturers 

 in the United Kingdom, but it is expected that a fair 

 number of Continental industries will be represented. 



The Industrie Blaller recommends the following formula 

 as furnishing a good and cheap writing ink : — French ex- 

 tract of campeachy wood 100 parts, lime water 800 parts, 

 phenol (carbolic acid) 3 parts, hydrochloric acid 25 parts, 

 gum arable .30 parts, red chromate of potash 3 parts. The 

 extract is first dissolved in the lime water on a steam bath 

 ■with frequent stirring or shaking, after which the carbolic 

 and hydrochloric acids are added, and change the red colour 

 to a brownish yellow. It is then heated half an hour on 

 steam bath and set aside to cool. It is next filtered, and 

 the gum and bichromate, dissolved in water, are added. 

 Enough water is then added to make up the solution to 

 1,800 parts. This ink is a fine red when used, but soon 

 gets black. 



By permission of Messrs. Chapman & Hall, a shorthand 

 edition (Pitman's system, easy reporting style) of the 

 " Pickwick Papers " is to be published, in weekly parts of 

 24r pp., crown 8vo, in cover, price 3d., to be completed 

 in twenty parts. The first part will be published May 1. 

 This will give many an opportunity of studying the 

 system easily and pleasantly. 



The Cambridge University Press is about to publish 

 the second part of the first volume of the " Treatise on 

 Natural Philosophy," by Sir W. Thomson and Professor 

 Tait. Many will hear with regret that the original 

 design of the authors, in commencing this volume about 

 twenty years ago, is not to be carried out beyond the com- 

 pletion of the first volume. The most important part of 

 the labour of editing this second part has been borne by 

 Professor Darwin. An index has been prepared by Mr. 

 Burnside, and schedules of the alterations from the first 

 edition and of new matter introduced into both parts will 

 be added. 



It is also announced that the University Press will 

 publish presently the volume completing Jlr. C. A. M. 

 Fenncll's edition of Pindar's Remains, " Notes on Quali- 

 tative Analysis," and " Tables," by Mr. H. J. H. Fenton 

 (Demonstrator of Chemistry in the University), and a new 

 edition of Mr. Wallace's " Outlines of the Philosophy of 

 Aristotle." 



"Forestry." — With the commencement, in May, of its 

 ftext volume, llie Journal of Forestry, still conducted by 

 Mr. F. C Heath, "Author of "Autumnal Leaves " and 

 Editor of Gilpin's " Forest Scenery," will take a " new- 

 departure." Under the altered title of Forcstrj/ : a Jfaqa- 

 zine for the Country, it will be enlarged in size and still 

 further popularised. The May part will include a descrip- 

 tive article by Jlr. Richard Jefleries, entitled " The 

 Contents of Ten Acres," and " A Forgotten President of 

 Agriculture," by Mr. R. A. Kinglake. 



In' answer to a number of inquirers, I must explain that 

 I know nothing, of my own kno-vvledge, about any system 

 of artificial memory. 



SOCIAL DYNMIITE. 



By Richard A. Pkoctor. 



IF we consider why men look with special horror at the 

 miscreants who use dynamite and nitro-glycerine with 

 the hope of destroying their enemies, we see that it is not 

 the cowardice, or even the malignity, of the act which 

 chiefly excites that feeling, but the recklessness with which 

 to destroy certain persons they run the risk, or rather incur 

 the certainty, of injuring many who are not among their 

 enemies. Among social offences there is one which in this 

 respect is akin to the use of explosives — writing anonymous- 

 letters. An anonymous letter of the libellous sort is an ex- 

 plosive which may or may not injure the person or persona 

 attacked, but is tolerably sure to injure others. It may de- 

 nounce one or several in such a way as to lead those to- 

 whom it is addressed to imagine that there may be some 

 truth in the attack — villanous though the source may be- 

 from which it came. These, of course, are the oVijects of the- 

 anonymous writer — to give pain to those attacked, and to 

 cause doubt and suspicion to their friends and relatives. 

 He may fail in this, because many have sense enough to- 

 consider that no reliance whatever can be placed on the 

 statements of one who is ashamed to be known, and they 

 may have confidence also (though this is harder) that none- 

 of their friends can for a moment put faith in statements- 

 emanating from a self-proclaimed, though unknomi, rascal 

 But there is one form of mischief, one kind of doubt, 

 which an anonymous letter is sure to produce. The person 

 or persons attacked may despise, as they should, an attack 

 so base ; the persons before whom the anonymous charges 

 are brought may, as they should, reject them as utterly- 

 unworthy of credit, coming as they do from a discreditable- 

 source. But though they may not be troubled by the 

 belief that the particular offences brought before then* 

 by an admitted liar have in them any shadow of truth, 

 they and all who hear of the anonymous charges 

 become certain that there is villany somewhere. And who 

 shall say ivliere ? Usually, an anonymous letter- writer is 

 so clover in disguise, that it has been well and truly said, 

 the author of an anonymous letter may generally be 

 taken to be the la^t person who is likely to be suspected. 

 But what a range of doubt and suspicion this idea covers. 

 All whom we look on as likely to be truthful and 

 generous, brave and outspoken : all who might be supposed 

 to respect themselves ; all who are worthy, as we think, 

 of any respect from others, are included among those 

 whom -we should consider the last to plan the villany of 

 an anonymous letter. Those whom we should suspeck 

 naturally are those whom we supposed to be sly and 

 treacherous ; but usually it turns out that the real traitor 

 is one who has a depth of slyness and treachery beyond 

 the range of this suspicion — one who has been clever 

 enough to hide slyness and treachery by superior craft and 

 deeper villany. 



And as in dynamite plots there is an element of dsingar 

 in attempts which may be made to unravel the secret — 

 danger in which the miscreant author of the plot finds- 

 safety — so it is with anonymous letters. To trace the letter 

 to its source may require — in fact usually does require — 

 that its contents — or at least the nature of the attack in it — 

 should be publicly announced. This brings the anonymous 

 charges to the knowledge of many who may not, like his 

 immediate friends, know enough of the true character of 

 the person attacked to reject at once false charges against 

 his reputation. The wicked and mischievous proverb, 

 " There is no smoke without fire " — as lying a proverb 

 as ever deceived the unwise — is held by many to be 

 a truth, as if it had not again and again been shown 



