Mar. 14, 1872] 



NATURE 



393 



1 1. 15 r.M. — A deep red glow from E. to W. by S. along the 

 horizon. Fourteen parallel bands of a silvery colour, with dark 

 bands between them. They lie south and north, occupying 

 nearly the whole southern hemisphere as far as the eye can reach, 

 and are flanked at east and west by patches of blood and cherry 

 red. 



11.24 P.M. — The bands have disappeared. There 13 a deep 

 red glare at E.S.E. and a lighter one at W.S.W. 



1 1. 28 P.M. — A few faint bands on either side of Canopus. A 

 red light on their western, but none on their eastern side. 



II. 31 P.M.— A dark red glow at W.S.W. , about 12° above the 

 horizon. 



11.33 P-"'- — Clouds gathering in the lower regions of the at- 

 mosphere. ^ 



11.37 P.M. — Two parallel faint beams of whitish hght 2 to 

 3° east of Canopus. A faint red glow at W.S.W., about 10° 

 above the horizon. 



11,42 P.M.— Two broad bands of faint whitish light to west- 

 ward and three to eastward of Canopus. A patch of red hght 

 still at W.S.W. near horizon. 



1 1.46 P.M. — Clouds gone. Aurora gone. 



11.49 P.M.— A faint red glow at W.S.W. about 10° above the 

 horizon, and a band of faint greyish light about 2° west of 

 Canopus. 



1 1. 5 1 P.M.— The glow at W.S.W. is brighter and higher. 



11.58 P.M. — Much fainter. 



0.34 A.M.— A segment of dark red light from S.E. by S. to 

 W.S.W., and rising at its middle to about 45° above the horizon. 



1.20 A.M.— A bright red glow from S E. to S.W. Intensest 

 below the Centaur. Soon died away. J, Meldru.m 



Royal Alfred Observatory, Mauritius, February 6 



GEOLOGY 

 Supposed Legs of Trilobites* 



Mr. Henry Woodward, of the British Museum, In a reply 

 to the paper by the writer in vol i., p. 320, of the present series 

 of this Journal, supports the view that the supposed legs are real 

 legs. He says that the remark that the cilcified arches were 

 plainly a calcified portion of the membrane or skin of the under 

 surface is "an error, arising from the supposition that the matrix 

 represented a part of the organism." But Prof. VerriU, Mr. 

 Smith, and myself, are confident that there is on tlie specimen 

 an impression of the skin of the under surface, and that this sur- 

 face extended and connected with the arches, so that all belonged 

 distinctly together. 



Moreover the arches are exceedingly slender, far too much so 

 for the free legs of so large an animal ; thediamder of the joints 

 is hardly more than a sixteenth of an ineh outside measnre ; 

 and henee there is no room inside for the required miiseles. In 

 fact legs with such proportions do not belong to the class of 

 Crustaceans. Moreover the shell (if it is the shell of a leg in- 

 stead of a calcified arch) is relatively thick, and this makes the 

 matter worse. 



We still hold that the regular spacing of these arches along 

 the under surface renders it very improbable that they were legs. 

 Had they been closely crowded together, this argument would be 

 of less weight ; but wliile so very slender, they are a lourth of 

 an inch apart. Mr. Woodward's comparison between the usual 

 form of the arches in a Macrouran and that in the trilobite does 

 not appear to us to prove anything. We therefore still believe 

 that the specimen does not give us any knowledge of the actual 

 legs of the trilobite. Mr. Woodward's paper is contained in 

 vol. vii.. No. 7, of the Geologieal Ma^vzine. 



J. D. Dana 



PHYSIOLOGY 

 Blood Crystals 

 An interesting volume has just been published by M. W. 

 Pieyer on Blood Crystals. The literature of this subject, 

 which dates no farther back than 1840, is already e.stensiye, no 

 less than 143 authors being quoted in the " Bibliography, some 

 of whom, as Bottcher, Hoppe-Seyler, Kiihne, Lehmann, RoUett, 

 Valentin and M. Preyer himself, have wntten many separate 



essays on points bearing more or less directly upon the crystallisa- 

 tion of the blood. Though blood crystals were first observed by 

 Hiinefcld, the merit of discovering them is due to Reichert, who 

 first recognised their nature. The fact of the ciystallisation of a 

 complrx organic substance like blood was first received with some 

 amount of increduUty, but the corroborative testimony of m my 

 microscopistssoon cleared away all doubt, and a varietyof methnd s 

 were suggested by which the crystals could be obtained. The 

 best plan for obtaining them is thus given by M. Preyer. The 

 blood is received into a cup, allowed to coagulate, and placed in 

 a cool room for twenty-four hours. The serum is then poured 

 off, and a gentle current of cold distilled water passed over the 

 finely divided clot placed upon a filter until the filtrate gives 

 scarcely any precipitate with bichloride of mercuiy. A current 

 of warm water (30° — 40° Cent.) is now poured on the clot, and 

 the filtrate received in a large cylinder standing in ice. Of this a 

 small quantity is taken, and alcohol added drop by drop till a 

 precipitate falls from which an estimate may be made of th; 

 quantity required to be added to the whole uithont producing a 

 precipitate. The mixture, still placed in ice, after the lapse of a 

 few hours, furnishes a rich crop of crystals. The forms of the 

 crystals obtained from the blood of different animals do not vary 

 to any great extent, and arc all reducible to the rhombic and 

 hexagonal systems. The vast majoriiy are rhombic prisms, more 

 or less resembling that of man. The squirrel, however, Avith 

 several of the Rodentia, as the mouse and rat. and the hainster, 

 are hexagonal. The ha:moglobin of several corpuscles is re- 

 quired to^form a single crystal. All blood crystals are double 

 refracting. The animals wlnse blood has been hitheito exa- 

 mined and found to crystallise, are— man, monkey, bat, hedge- 

 hog, mole, cit, lion, puma, fox, dog, guinea pig, squirrel, 

 mouse, rat, rabbit, hamster, marmot, ox, sheep, horse, pig, owl, 

 raven, crow, lark, sparrow, pigeon, goose, lizard, tortoise, ser- 

 pent, frog, dobule, carp, barbel, bream, rudd, perch, herring, 

 flounder, pike, garpike, earthworm, and nephelis. The spectrum 

 of blood-colouring matter m hen oxidised with its two absorption 

 stria- between D and E of Fraunhofer's lines or in the yellow 

 part of the ordinary spectrum, and the single band of deoxidised 

 hemoglobin, are now well known. M. Preyer states he has not 

 been able to obtain a spectrum from a sin:^Ie blood corpuscle, but 

 that the characteristic bands are visible where certainly only a 

 very few are present. The specific gravity of dry hcemoglobin 

 he gives at about 1-3- 1-4- The solubility of the crystals 

 obtained from different animals varies considerably. Those 

 of the guineap'g and squirrel dissolving in water with great diffi- 

 culty. Ha-moglobin is msoluble in absolute alcohol, ether, the 

 volatile and fixed oils, in benzole, turpentine, chloroform, and 

 bichloride of carbon. It is easily soluble in alkalies ; acids 

 rapidly decompose it. He calculates out for it the fearful formula 

 of C„|||, Hgi,,, N154 Fe, S., Oi-g, as agreeing very accurately with 

 the percentage results of its analysis. Its equivalent is 4444, 4. 

 Many pages of M. Preyer's work are occupied with an account 

 of the action of various reagents upon it. The plates contain the 

 forms of the principal crystals, and thirty-two spectra lithographed 

 in colours. He describes five crystallisable products of the de- 

 composition of hemoglobin, namely, hemin, hematosin, ha^a- 

 toidin, ha:matochlorin, and hematolutein, and several uncrystal- 

 lisable. such as methemoglobin, ha-matin, and hamathion. 



H. P. 



From the ^> 



( Journal of Science and A rts for March 1 



SCIENTIFIC SERIALS 



Anualen der Chemie unJ F/tarmacie, Septembei 1871. — 

 Kochlin has continued his researches on " compounds of the 

 camphor group." By the action of nitric acid on camphor the 

 author has obtained a new body, C,|Hj.,0.., which he calls cam- 

 phoronic acid, and which has the property of forming salts in 

 which H., and H., are replaced by metals. By distillation with 

 potassic hydrate, butyric acid is produced ; with bromine in pre- 

 sence of water camphoronic acid is oxidised, yielding oxy-cam- 

 phoronic acid ; this acid forms salts, in which Hj, H„, and H., 

 are replaced by metals. — An important physiologico-chemical 

 paper follows by Hlasiwetz and Habermann on "Proteids," 

 and a paper by Naumann on the length of lime for the evapora- 

 tion and condensation of solid bodies," which, however, do not 

 possess much general interest. — Bender contributes a paper on 

 the " hydrate of magnesic oxychloride." This substance, how- 

 ever, does not appear to be very stable, or to have very marked 

 properties. — Mulder has experimented on allantoin and bodies 



