44 



♦ KNOWLEDGE ♦ 



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able. 



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•'In knowledce, that 

 •t«te of tnumition. . 

 lli»n_flxitT of opinion."— F'T^rfdy. 



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•There i _ 



mistakes, and . 

 hine."— TliVi.o. 

 ' God's Orthodoxy is Truth."— Oar^* J! 



(Pur Coiffsipoiitifnrf Columns. 



METACIIROMATISM. 



[427] — There are a few mistakes in Colonel Ross's latest commu- 

 nication to Ton (Knowlkuge, Juno 9, p. 25), which, since they 

 involve aspersions on my character, I trust you will allow me to 

 set right. 



These are the tmo facts of my intercourse with Colonel Ross. 

 In April, 1874, I laid the JIS. of a projected research on inorganic 

 colour-change before Professor Franklaiid, of the Royal College of 

 Chemistry, Sonth Kensington. I commenced the experimental 

 work of the research as soon as ever my duties would allow me, 

 viz., in the first week of October, 1875. When my work was com- 

 pleted fone day in December), the late Mr. Valentin brought Colonel 

 (then Major) Ro.'fs, and introduced him to mo at my table in tlio 

 laboratory. I was then given to understand thatMajor Ross's 

 b<>ok on Pyrology was in the press, lie promised to send Mr. 

 Valentin a co[iy, which that gentleman never received, as it after- 

 wards transpired that either Major Ross or his agent sent the book to 

 the Museum authorities, and they quietly deposited it on one of the 

 librarj- shelves. I had no knowledge whatever of Colonel Ross's 

 colour speculations, which, by the way, I now hohl, and can prove 

 crporiracntally, to bo erroneous. Colonel Ross's statements on those 

 matters have been denied before, many years ago, and I beg to 

 refer your readers to a letter from Mr. Wra. A'alentin, in the 

 Cherracal Newt of Sept. 22, 187C. 



But to return to the fortunes of my paper. There was certainly 

 great delay in the printing of it. In the first place, it was not read 

 until a month after being announced, because of my having to go 

 on an expedition in connectionwith the Loan Exhibition of Scientific 

 Apparatus, which was then being organised. It was read in 

 Kcbmary. After months of delay I was requested to cut it down 

 for reconsideration by the publication committee. This was done ; 

 but for some reasons, best known to themselves, they decided the 

 subject was not suitable for their jonmal. Hero Colonel Ross 

 comes in with a glaring error, to call it by no worse a name. The 

 article in the Chemical Xeira, towhieh ho refers as having influenced 

 the Chemical Society's Committee, did not appear in print while 

 they were considering the matter, but a while after, and it was 

 from Colonel lioss's own pen. It is a communication he must have 

 ofU'n regretted, m it stands there in the Chemical NewK for Sept. 8, 

 187C, a monument against him. When the Chemical Society 

 refused my paper,! sent it at once to Mr. William Crookes, who 

 very kindly had it printed at once. 



Wm. Ackboto, 

 Fellow of the Inst, of Chemistry. 



[Wo hasten to insert Mr. Ackroyd's correction of Colonel Ross's 

 statonicuts. It is evident there must liavo 1 nen Fome misappre- 

 hension ou the part of the latter as In ilu' . uli i- in which events 

 happened. Space is too limited to < i :ili!i u^ ;,. iii„l further rotm 

 for matters rather personal than Fiiini ill. ; m il.at unless Coloi.el 

 Ross is able to show that the dates nu i i i. i.i li 1 v Mr, Ackroyd r.ro 

 inc-orroct, or to make other correction.'; EiiscrptiMe of definite veri- 

 ficaiiim, our readers will not hear more about these matters. Rut 

 we are sure they would gladly welcome Sir. Ackroyd's account of 

 any exjieriments bearing on the scientific <iuoEtions at issue. — Ed.]1 



TUE IIUUILAND CELT. 



[428] — In a recent number of Kxohi.edge, Mr. Grant Allen 

 makes the following stiitement (p. 550) : — " The so-called Celts of 

 . . . .the Highlands are, for the most part, dark-haired and dark- 

 skinned poojile." This is totally opposed both to history and fact. 

 I do not speak of the Islanders, who are a very mixed race, but the 

 Higlilaiulcrs of the mainland, who have always been a brown-haired 

 race. Their very namo of Caledonians, which is Gaidhill-dhonna, 

 or brown-haired Gaels, implies this. Calcdonii, in the mouth of a 

 Roman, and Gaidhill-dhonna in the mouth of a Scottish Highlander, 

 are almost, if not entirely, identical. Then wo have the evidence 

 of Tacitus and of our ancient genuine Gaelic imotry. Amongst 

 many others, refer to Tacitus's "Lifi ■!' A i i. In," c. xi. ; Alexan- 

 der and Donald Stewart's " Highlm. I i: ;71 75; and Mr. 

 Firbis's genealogies quoted in "(1 ■> 1 lurcs," p. 223. 

 Turning to fact, I asked a schoolnm i t r 1 i : i! II .iie, and out of 

 120 children in his school, 118 had brown Iniirof ii darker or lighter 

 hue. 1 also asked a drill-instructor, and in a company of tG, above 

 80 had tlie same character. 



It is true that in some parts, chiefly in Cowal, in Argyllshire, 

 there arc a very few black-haired Gaels. These, however, are not 

 genuine Gaels, but descendants of the Fir-bolg, who were in Ireland 

 before the Gaels, but being conquered, and having submitted, were 

 incorijorated with the true Gaels. To distinguish them from these, 

 they were named Tion-gall. From Ireland they passed to the Isle 

 of Man and Cowal. Charles Stewaut. 



TUE FEVER TREE. 



[429] — Allow me to call 3-our attention to errors in the note 

 on the " Fever Tree," pr.ge 608 [which was inserted by mistake — 

 having been scored out from a column of other matter, but in pencil 

 only. — Ed.] " The bark yields a febrifuge second only in efticienoy 

 to quinine, but superior in all medical qualities to cinchona." 

 Quinine is an alkaloid, cinchona the genuine namo of the various 

 species of cinchona. There is an alkaloid called cinchonine, about 

 the sixth part of the price of quinine, but as the only product of 

 Eucalyptus at all know in this countJ-y is the essential oil, and the 

 decoction of the loaves has proved a failure, I cannot understand 

 the comparison. A febrifuge is said to reside in the bark, you will see, 

 but I have not heard that it has been extracted. 



Whether the tree will grow in " the eastern and middle states" 

 does not much interest us, but as it is extremely impatient of frost 

 (perhaps I should say patient, for it dies off (piietly), I do not sup- 

 pose it will. There were a fair number of trees in the south of 

 England and Ireland that had gratified the hopes of the planters 

 until the recent winters swept them all, I believe, away. I do not 

 think it is acclimatised as yet in Italy, where a number have been 

 planted in the Campagna; but I believe it has answered in Algeria 

 better than in Euiopo. It is, of course, incorrect that the tree 

 " produces no fruit or nut." W. SciiiTnALt, 



Pharmaceutical Chemist. 



SIDEREAL TIME. 



[430] — Amateur astronomers will thank "Ocean" for his com- 

 munication of a " neat method " of ascertaining the approximate 

 sidereal time at noon for any day in the year. 



Will yon permit mo to send his "neat method" reversed, by 

 which any one may be enabled, without an ephemeris, to calculate 

 from the sidereal time at noon any day in the year. 



For instance, to the constant 3'22 add the hours of sidereal time 

 divided by 2, and also the minutes divided by 4. Taking his own 



example, we find that to the constant 322 



Sidereal hours + !• 



Minutes + 013 



5-5 

 Tlio result will bo the fifth day of the fifth month, or May 5. 



This "rovereod method" is useful for finding the day on which 



I 



