iVov. 7, 1878] 



NATURE 



reptic ferment is very rare among invertebrates ; a ferment 

 ilar to thrypsine, on the other hand, is met with among 

 ..;:'erent clas.-es of these animals. — M. Plateau communicates 

 an account of experiments (with the graphic method and poisons 

 of the heart), on the movements and innervation of the central 

 organ of circulation in articulate animals- Inter alia, section of 

 the cardiac nerve diminishes the number of pulsations (in verte- 

 brates, it produces acceleration). — M. Renard describes the 

 diabase of Challes, near Stavelot, in the Cambrian system. — Dr. 

 Koninck continues his researches on Belgian minerals ; and there 

 are some papers on mathematical subjects. 



The Bulletin de V Acadimie Imperiale des Sciences de St. Petert- 

 bourg (vol. XXV. No. 2) contains the following papers of in- 

 terest : — On the occurrence of the musculus peroneo tibialis in 

 Quadrumana, by Dr. Wenzel Gruber. — On a control barometer, 

 by H. Wild (with plate). — On the reduction of Kirchhoflf's 

 spectral observations to nave-lengths, by Dr. B. Hasselberg. — 

 On the observed ingress of Mercury upon the solar disc, at the 

 transit of 1878, May 6, by O. Struve, of Pulkowa (with plate), 

 — Catalogue of forty-two new red stars, by E. Lindemann. — 

 On the Russian species of the mollusc Clausilia, Drap., by Dr. 

 Oskar Boettger. — On the theory of curves of the shortest para- 

 meter on curved surfaces, by F. Minding. — On the hexylenes 

 resulting from tertiary hexyblcohols and their polymerisation, 

 bj.' L. Jawein. — On the action of tertiary iodide of butyl upon 

 i>obutylene in the presence of metallic oxide?, by J. Lermontoft. 

 — On tetramethylethyl and its derivates, and. on the chemical 

 composition of pinacone, by D. Pawlow. 



TTie yournal of the Russian Chemical and Physical Societies of 

 Sf. Petersburg (vol. x. No. 6) contains the following papers of 

 interest : — On tetramethylethylene and the chemical structure of 

 pinacone, by M. D. Pavloff. — On the glucose derived from 

 ■actose, by M. Foudakovsky. — On the action of bromide of 

 iluminium in the formation of the bromides of aromatic hydro- 

 :arbons, by G. Gustavson. — On the dextrogyrate terpens 

 'btained from Russian terpentine, by F. Flavitzky. — On the 

 :hemical structure of terpenes, by the same. — On dibenzoyl- 

 iinitrodiphenol, by M, Goldstein. — On some new mineral 

 ;pring3 in the Caucasus, by E. Wroblewsky. — On the influence 

 bf the surrounding medium upon electrodynamical actions, by J. 

 Borgmann. — On the determination of the magnetic function of 

 iquids, by the same. 



Verhandlungen der naturforschcnden Gesellschaft zu Freiburg 

 . B. (vol. N-ii. part 2) . — From the part we note the following 

 lapers : On organic cyanides and their decomposition, by A. 

 Claus. — Note on wine, analysis, by the same. — On the equili- 

 :)rium of a system of expanded molecules and the theory of 

 ;lastic after effects, by E, Warburg. — Observations on the 

 orsion oscillations of an iron wire heated to redness, by Dr. 

 Messer. — On the sensitiveness of alum crystals towards minute 

 ariations in the concentration of their mother-liquor, by F. 

 \locke. 



SOCIETIES AND ACADEMIES 



Cambridge 



Philosophical Society, October 21. — Dr. Pearson read a 

 ;aper on a series of lunar distances taken by him during the 

 rears 1875-77, mostly at Cambridge and at a place not far distant, 

 he longitude and latitude of each spot being accurately known, 

 le said that they entirely bore out the conclusions at which he 

 lad arrived some time back from a much smaller number of 

 >bservations, and which were communicated by him to the 

 Society in a paper read by him, March 13, 1876 (see Proceedings, 

 ;i. pp. 414-418), viz., that the errors are such as cannot be 

 ! ailed errors of observation of any kind, and may probably arise 

 rem the solution of the spherical problem on which the result 

 epends not being, as at present given, strictly accurate. It 

 • as mentioned that there is much to justify this conclusion ; for 

 Kample, this method of obtaining longitudes is not much resorted 

 JO now in practice (from which it may be argued that it is actually 

 lound inaccurate). It is not formally adopted in Germany, 

 jhough it still is retained in the Nautical Almanac, and in the 

 jorresponding publication, the Connaissance des Temps, issued 

 jt Paris. Capt. Toynbee, F.R.A.S., in a paper in the Nautical 

 iiagazine for February, 1850 (of which there is an abstract in 



" Monthly Notices oi the R.A.S,), distinctly states that lunars 



taken ea't of the moon give always a result thirty or fortv 

 seconds different from those taken west, though his mean result 

 he says was entirely satisfactory ; and until the early part of this 

 century all East Indian longitudes were in error nearly 3m. to 

 the east, a result which very nearly agrees with the errors resulting 

 from these observations, supposing them to have been deduced 

 from the new moon of five to eight days old, probably the most 

 convenient time at which to take them from the sun. The whole 

 series, it w-as stated, consists of 250 separate distances, each dis- 

 tance being either a mean of three or two, or else only one 

 observation, there being about an equal number of each class, 

 though there is no reason to think that the last are less trust- 

 worthy than the others in any serious degree ; the Greenwich 

 mean time for each being established, with the exception of a 

 very few, within certainly ten seconds. Only 200 of these, the 

 number at present thoroughly verified, were discussed on the 

 present occasion. Classing these in groups of about forty, it 

 was found that the first group gave thirty-two results where the 

 measured distance was in defect of the theoretical distance, and 

 thirteen in which it was in excess. Assuming the rule given in 

 p. 417 of the paper referred to to be correct, this result exactly 

 agrees with what might be expected, it being almost always most 

 convenient, especially for a beginner, to take lunars, at any rate 

 from the sun, under such circumstances as will give this result, 

 while the example of India, founded apparently on observations 

 made at Madras, seems to imply this probable facility, and 

 also that they were made on the new moon, these being more 

 easily taken in our hemisphere than those made on the old one. 

 In the four remaining groups the proportions are 26 to 18 : 28 

 to 15 : 25 to 17 : 17 to 14 : giving a total of 128 observations in 

 defect, and 77 in excess. Rejecting three or four certainly ques- 

 tionable results, the" greatest errors occurring are 2' 59' in defect, 

 and 2' 48" in excess. The true mean has not yet been ascertained, 

 but is certainly in each case not far from 1' — i' 20" ; which, on 

 an average, will give the obsers'er an error of about half a degree 

 of longitude, or of twenty to thirty-five miles, advancing from 

 our own latitude to the equator. There are probably not a 

 dozen clear exceptions to the rule suggested in the commimi- 

 cation of March, 1876, that if the luminaries are both on the 

 same side of the meridian, the obser\-ed distance is always in 

 defect of the true if the moon be nearest to it, and in excess if 

 she is farther distant ; while the same rule holds good, but with 

 less certainty, when the two luminaries are on different sides. 

 The only exceptions seem to arise where the one more distant 

 from the meridian has a greater altitude than the other, or is of 

 a considerably higher declination, and when the distances are 

 very great, i.e. from 120° to 130°, in which case the measured dis- 

 tance seems generally to be slightly in excess of the true ; but, as 

 might naturally be expected, these last distances cannot often be 

 taken in our own climate. It was explained that all the reductions 

 had been made by Borda's formula, stated in the Philosophical 

 Transactions for 1797 to have been the first strictly mathe- 

 matical solution of the problem. But the results vary only by a 

 few seconds of arc from those given by the system adopted in 

 the large folio published in 1772 by Mr. Shepherd, Plumian 

 Professor at Cambridge Univer ily under the superintendence of 

 the Commissioners of Longitude, and while Dr. Maskelyne was 

 Astronomer-Royal ; or from other methods which it is believed 

 are allied to this. Two examples were also exhibited of dis- 

 tances reduced according to the elaborate method suggested by 

 Bessel in the Astronomische Nachrichten of 1832 ; Bessels 

 results, however, do not differ to any great extent from those 

 obtained otherwise. It was suggested that the problem is really 

 one of spherical trigonometry, and from the fact that the errors 

 seem to depend on the position of the luminaries towards the 

 meridian, whereas the old methods of solution depend on their 

 altitudes, and also that the different ways suggested for elimi- 

 nating the error due to the difference between the geocentric and 

 geographical latitude of the place cf obser\'ation give different 

 results, a hope was expressed that if these two circumstances 

 were thoroughly reconsidered in dealing with the- question, 

 means might be found of discovering a farther correction of the 

 observed distance, which would give a really accurate result, 



Manchester 



Literary and Philosophical Society, October 15. — ^J. P. 

 Joule, F.R.S., &c., president, in the chair. — Relative brightness 

 of the planets Venus and Mercury, by James Nasmyth, C.E., 

 F.R.A.S., Corresponding Member of the Society. "On many 

 occasions, when observing Mercury and Venus in fall daylight. 



