43S 



NA TURE 



[September 5. 1895 



same night, which varied with the lengths of path from about 

 05 to 07 sec., the velocity deduce*! would \>i between 39 and 

 27 miles per second, fairly agreeing with the real meteor-speed 

 of the Perseids, which is 38 miles per second. 



It would be interesting to learn if any observations were made 

 elsewhere of a meteor seen at Tring at 9.32 P.M. on the 19th 

 inst., descending from near the zenith at 3171 + 37, southwards 

 to 320+ 15, which exceeded the fixed stars in brightness, and 

 which was brilliant enough to attract the attentions of ordinarj' 

 wayfarers there ; so that with this observation of its path at 

 Tring, its real course, and the position of its radiant-point in 

 the northern sky might be determined. A. S. Herschel. 



Ot»er%atory House, Slough, Bucks, August 29. 

 3 



Do the Components of the Compound Colours in Nature 

 follow a Law of Multiple Proportion .' 



Ox examining the data contained in Mr. I'illsbury's interest- 

 ing and valuable risiim^ on colour measurements in the United 

 States, by means of ordinates and abscissa; for the various 

 colours on squared paper, it became at once evident from the 

 parallelism of the diagonals which could be drawn that, although 

 previously hidden, there was a numerical relation underlying 

 them, and that probably the measurements would furnish an 

 affirmative answer to the question printe<l at the head of this 

 letter. Can it |K>ssibly be that those compound colours which 

 occur with such profusion in nature are the result .of simple 

 colours being combine<l in definite multiple proportions ? Can 

 there be a law of multiple proportions here, similar to that which 

 holds good in the domain of chemistry .' 



Let us see how far the data which Sir. I'illsbury gives support 

 such a conclusion : they cannot from their iiau'city prove it. If 

 we lake all the foliage greens given, raise the percentage of 

 black to 100 in each case, and proportionately increase or 

 decrease the yellows and greens, then the amount of yellow in 

 each case divided by the amount of green in each case will give 

 a ratio which, the black Ix'ing equal, may be said to represent in 

 figures the colour of the [xirticular foliage. Now what do we 

 find on examining the resulting ratios? They are all divisible 

 into groups of multiples of 2, which may be represented as in 

 the last column of the table by i-V, 2-Y, yW It will be noticed 

 that while the figtire in the second decimal place is not exactly 

 a multiply of 2, yet it tends very much in that direction. 



Of course the conclusion reached cannot by any means be 

 con.sidcred proved, as we do not know if the foliage greens were 

 selected by .Mr. I'illsbury pur|K)sely, or were merely the result 

 of purechance : but it would stem amply to repay further invesli. 

 galion, and I should be plejLsed to hear that .Mr. I'illsbury could 

 undertake it, or, if he feels unable, but would furni.sh nie with 

 the nccessar)' material, I would try and undertake il myself. 



A-s nmch stress is laid upon the commercial utility of this 

 system of colour mea.surement, might I .suggest that in .-ill cases 

 I he simple colour of which there was the largest (piantity shotild 

 liu- taken as mea.suring loo? liy this means there would always 

 lie 'inc less numlicr to recollect, write, or telegraph, than there 

 are .i.....!. ..Inurs in the compound — no small factor when 

 <lc.' rge ■luantities. !•". HOWARD Coi.l.lNs. 



' , ICdgliaslon. 



Transformation of Moulds into Yeasts. 



TllK experiments carried out in Dr. Jiirgcnscn's lalmralory in 



Co|>ciili;ii.'i 11. ■.II iln- iii'irphological relations of moulds and 

 yc.i ' , and have an im|virlant liearing upon 

 th' ■'■ method of jrt/*/.brewing, an inves- 

 " I 



y 



liyaliun of uIulIi ■A.t-. made by the writer whilst in Ja|xin, ant: 

 the rc.<tult.< of which were published by the National Univcrsilj 



fibres of the mycelium, and this product {ii>/t), mixed with 

 fresh sleamed-rice and water, is placed in ma.sh-tuns and slightly 

 warmed. After a short time active fermentation sets in, result- 

 ing in the preparation of a liquid {saic') containing as much as 

 15 per cent, of alcohol. The question as to the origin of the 

 ferment-cells was discussed in the memoir above referred to, and 

 the conclusion was arrived at that there was no evidence to show- 

 that the mycelium underwent any change, but that the ferment- 

 cells were derived either from the air, or from the vats, or 

 from spores which had attached themselves to the .surface 

 of the mycelium. Microscopic ilrawings were given illustrating 

 the appearance of the ma,sh at various periods during the fer- 

 mentation, and in these the mycelium was seen to preserve its. 

 original form to the end of the i>rocess. The feature iipon which 

 most stress was laid by those who asserted that the mould was 

 converted into the ferment, was the suddenness with which the 

 fermentation showed itself, of which fad there could be no 

 doubt ; but it seemed to the writer that there was a vcrj- simple 

 explanation of this. The fermentation aiipears inuiiediately 

 after the warming of the mash, which has already been exposed 

 to the air in shallow vessels at a low temiicrature for several 

 days before being collected into a single vat. It is also allowed 

 to stanil in this vat for several hours before heating, during 

 which time probably all the dissolved oxygen has been used up 

 by the ferment. By healing, the temperature is then raised to 

 about 25 C, a condition very favourable to the growth of yeast. 

 Knowing how rapidly the yeast jilant buds under such con- 

 ditions, it does not seem necessary to invoke the transformation 

 of the mycelium into ferment-cells to account for the sudden 

 appearance of the fermentation. 



The note (N.mi'rk, .-Uigusl 22, p. 397) further says that 

 Juhler found in his Hasks in which the Japanese mould, .-/x/r-;- 

 gilliif oryzic (called Eiiroliiim oryur in the writer's memoir), 

 was cultivated a growth of typical alcohol-producing sacchar- 

 oniyces cells. If ihere were spores attached to the surface of 

 the mycelium, il seems neces.sary to know in what manner they 

 were destroye<l before the introduction of the mould into the 

 culture flasks. It w-ould also be interesting to have more details 

 of the size of these cells, to ascertain if they correspi.ind exactly 

 with tho.se found in the native Japanese fermenting vats. The 

 size of the full-grown cells measured by the writer weic on the 

 average 0-0082 m.m. in their longest diameter — that is, between 

 the dimensions of ordinary beer-yeast anil wine-yeast. 



I 'irdiflT, .-Xugust 24. K. \V. Atkinson. 



..f I- 

 1 



inoiilil i.H cau.se<l lo grow over the surface of 

 he grains are firmly matted togelh'-r bv ihi- 



NO. 1349, VOL. 52] 



l.N reply to Mr. Atkin,son's inquiries, we would refer him ii> 

 Juhler's origintil communication on his experiments with .■ls/>ir- 

 gi/liis oiyzic, to be found in part ii. of the CciitralblatI tiir 

 Haklcriohgic, Nos. I and 9, 1895. 



.\ugust 29. TiiK Writer ok thf. Noti.. 



Mr. Seebohm on MiddendorfTs Credibility. 



.Mr. Skkiioiim writes (aiitca p. 385) : "There is no reason to 

 believe that Middendorflever found the eggs of the little stint. 

 The eggs which he records as being those of Triiiga niiiitita were 

 ]irobal)ly those of Triiiga riificollis and possibly those of 

 Triiiga mhminiila." To me these statements seem made in 

 oblivion of the facts, and as some years .ago I exhibited in 

 London (Proc. Zool. Sof., 1861, p. 39S) one of ihe s|)eciiuens on 

 which doubt is thus thrown, I beg leave to show that there is no 

 rea.son for believing thai distinguished explorer to have Ix'en 

 mistaken. The only eggs he records (.V/V'. A'ti'si', II. ii. p. 221) 

 are four, the parent of which he caught under his game bag. No 

 other nesi is mentiimed, and this one was found on July i, 1843, 

 in the Taimyr )wnin.sula, which is admilleilly as well within the 

 range of 7". miiiiila, as il is outside of that recorded f<ir 7'. rii/i- 

 (ollis Uf. Palmen, VcgaE.xpcd. I'clcnskapl. Jakllagtlstr, v. tab. 

 4). Though not recognising these two birds as good species. 

 Vim. Midden<lorfl' ha<l rarefiilly noticed {loin. (it. p. 222) the 

 difference between examples obtained in Ihe far East (Orhotsk) 

 and in Ihe high Nortli (Taimyr), expressly stating that the latter 

 agreed with Xauniann's figure which unilouiiledly represents 

 T, iiiiniila in summer plumage. As to T. siihniiiiiita, 1 am not 

 aware of any evi<lcnce of ils occurrence in the Taimyr, and by 

 conjecture only can it be ascribed lo that di.slricl ; but ihe sup- 

 |X)Siliim that a single nest can have belonged to both '/'. riifiiolli<: 

 "and possibly" 7'. siiliiiiiiiula, is a masterpiece of conjecture 

 wholly alxjve my power of comprehension. 



Ai.iKKh Nkwion. 



Magdalene College, Cambridge, August 23. 



