342 



NATURE 



\Augtist II, 1 88 1 



North-West Africa, two Pantherine Toads i^Bnfo panlhiriuus) 

 from Tunis, on approval ; a Bennett's Wallaby {Haltnaturus 

 bennetli), born in the Gardens. In the Insectarium may now be 

 seen larvae of the scarce Swallow-tail Butterfly (Papilio poda- 

 lirius), also those of Attactis alias of various sizes, from ones 

 just hatched to ones nearly full-fed. Other noticeable larva: are 

 the curiously shaped ones of Siaiiropiis fagi, and young one-i of 

 the North American Sainia cayopia. Imagos of Attacus peniyi 

 are also emerging, reared from eggs laid in the Insectarium in. 

 the earlier part of the summer. 



OUR ASTRONOMICAL COLUMN 

 Gould's Comet-Observations on June ii. — Dr. B. A. 

 Gould, director of the Observatory at Cordoba, has communi- 

 cated to the Astrouomische Nachrichtcn particulars of his experi- 

 ences while observing the great comet of the present year on the 

 evening of June II. On that evening, he says, ''the comet was 

 found with but little difficulty, although considerably north of 

 the estimated place, being recognisable by its diffuse aspect, 

 elongated form, and large diameter, although it was quite pale 

 in the bright twilight, and the tail could not be seen." He had 

 just obtained a rough determination of its position from the 

 equatorial circles for the purpose of finding and identifying some 

 comparison-star, when he found one in the field. He considered 

 it to be some one of the many bright stars of Orion in the 

 vicinity, which would be readily identified, and hence did not 

 complete the approximate determination with the usual care, 

 nor obtain instrumental readmgs for the star. This he describes 

 as " only a little fainter than the comet itself, and not very di^ 

 similar in aspect : since, although its apparent diameter was 

 much less than the comet's, it was greatly blurred by the 

 exceptionally thick haze and the mists of the horizon, the zenith 

 distance being nearly 80°, I do not think it wfjuld have been 

 below the third magnitude, and could rather believe it to have 

 been as bright as the second." Dr. Gould adds: "Only four 

 comparisons were obtained before the comet passed below tlie 

 horizon ; then on attempting to identify the star, I found it in 

 none of the catalogues." 



On the next evening he examined the region without finding 

 any visible star, but Rigel was much brighter than the missing 

 object, and there was no visible object in the vicinity of the 

 coniit, which he found nearly three decrees to the northward. 

 The observations gave the following results : - 

 1881, June II, position of the comet from the circles of the 

 equatorial. loh. 5Sm. 9s. sidereal time. Right ascension, 

 5h. Mm. 4s. Decl. - 9° 36'. 



The comparisons with the star gave : — (Comet — star.) 

 Cordoba Sid. T. Diff. R.A. Diff. Decl. 



II II 55 ... -I- o 48-6 ... - 16-15 (- 5'8"-i). 

 Thus he deduced for the st.ir's position R.A. 5h. lom. i6s. 

 Decl. - 9° 30', where our catalogues have no conspicuous star. 

 In his letter to Prof Krueger he concludes thus : — 



"The whole observation has .seemed to me so improbable that 

 I have hesitated a good deal before sending it to you, fearing 

 some gross error in reading the circles. But I have discovered 

 none, and the later determination of the comet's geocentric path 

 will remove all uncertainties of this kind." 



On receiving these particulars Prof. Krueger, determined the 

 place of the comet fir the time of Dr. Gould's observation, from 

 the elements we published in this column, which were founded 

 upon observations between June 22 and July I, and finds R.A. 

 5h. Ilm. iSs., Decl. -9° 32' -o, and thence for the place of the 

 star R.A. 5h. lom. 26s., Decl. -9° 26' -9, showing only such 

 differences from the observed place as might be well attributed 

 to uncertainty of observation so near the horizon, and to tlie 

 corrections which the elements used probably required before 

 Che perihelion passage. Prof. Krueger remarks that no known 

 bright star exists in this position, and the star-chart of the Berlin 

 Academy for this region, which was formed by Dr. Schmidt, 

 shows here a great blank. He draws attention also to the signi- 

 ficant fact that the observed motion in declination in the interval 

 between the first and last comparisons is much less than thaj 



which the comet must have had ; the elements would indicate 

 about 45" or more than 2-3 revolutions of the micrometer-screw, 

 while the observations give only 0-5. Dr. Gould especially 

 remarks upon the resemblance of the object to the comet, and 

 Prof. Krueger suggests whether there could have been "eine 

 Verdoppelung des Cometen in Folge einer Luft.spiegelung," or 

 again was a second cornet observed ? 



The case is a very interesting one. With elements which 

 must give the comet's place on June 1 1 within a very few seconds 

 of arc. Prof. Krueger's inferences are fully borne out. Thus for 

 June 11-41962, Greenwich mean time, which corresponds to 

 llh. iim. 55s. Cordoba sidereal time, diminished by the time 

 for aberration, the right ascension of the comet is found to have 

 been 5h. iim. 13-Os., Decl. - 9° 35' 18", agreeing closely 

 with Dr. Gould's instrumental place obtained a few minutes 

 earlier, and tlie differential observations thus give for the ap- 

 parent position of the star, R.A. 5h. lom. 24-45., Decl. 

 -9° 30' ^o". There appears to be a misprint or an oversight in 

 Dr. Gould's letter as regards the zenith distance of the comet 

 and neighbouring object at the time of his observations, which 

 would be nearer 85° than So°. 



Scharerle's Comet. — The following elements of this comet 

 have been calculated by M. Bigourdan, of the Observatory at 

 Paris, from observations on July iS, 23, and 28 : — 



Perihelion passage, 18S1, August 22-60205, M-T. at Paris. 



Longitude of perihelion 33441 10) iir -c-- 



,, ascending node 96 48 23 > 00 !j^ 



Inclination 39 56 3S ) 



Log. perihelion distance 9-801 78S 



Motion — retrograde. 



Whence the comet's positions for midnight at Berlin, or about 

 llh. 6m. G.M.T., will be :— 



R.A. 



Decl. 



Log- Distance from 

 h. m. s. o . Earth. Sun. 



August II ... 7 54 o ... +52 7-6 ... 9-9307 ... 9-8307 

 13 ... 8 22 55 ... 52 45-6 ... 9-8973 ... 9-8218 

 IS ■•■ 8 57 39 ... 52 47-2 ... 98638 ... 9-8142 

 17 ••• 9 37 38 ... 5' 5i'4 - 9'S3i7 •• 9"8o83 

 19 ... 10 20 39 ... 49 36-7 ... 9-8031 ... 9"8o43 

 21 ... II 3 21 ... -f45 49-6 ... 9-7806 ... 9-8020 

 The comet was within naked eye vision on the morning of 

 July 29, and the intensity of light, according to theoiy, should 

 increase until August 25, about which time we miy look for a 

 pretty conspicuous object. The most favourable period for 

 ob ervation will be during the last ten days of August. 



THE CONNECTION OF THE BIOLOGICAL 

 SCIENCES WITH MEDICINE^ 



""pHE great body of theoretical and practical knowledge which 

 ■*■ has been accumulated by the labours of some eighty 

 generations, since the dawn of scientific thought in Europe, has 

 no collective English name to which an objection may not be 

 raised; and I use the term "medicine" as th.at which is least 

 likely to be misunder^tood ; though, as every one knows, the 

 name is commonly applied, in a narrower sense, to one of the 

 chief divisions of the totality of medical science. 



Taken in this broad sense, "medicine" not merely denotes 

 a kind of knowledge ; but it comprehends the various applications 

 of that knowledge to the alleviation of the sufferings, the repair 

 of the injuries, and the conservation of the health, of living 

 beings. In fact, the practical a.pect of medicine so far dominates 

 over every other, that the " Healing Art " is one of its most 

 widely received synonyms. It is so difficult to think of--medicine 

 otherwise than as something which is necessarily connected with 

 cur.ative treitment, that "e are apt to forget that there must be, 

 a: d is, such a thing as a pure science of medicine — a "pathology " 

 which has no more necessary subservience to practical ends than 

 has zoology or botany. 



The logical connection between this purely scientific doctrine 

 of disease, or pathology, and ordinary biology, is easily traced. 

 Living matter is chai-acterised by its innate tendency to exhibit 

 a definite series of the morphdogical and physiological pheno- 

 mena which constitute organisation and life. Given a certain 

 range of conditions, and these phenomena remain the same, 

 within narrow limits, for each kind of living thing. They 



I Address at the International Medical Congress. By Prof. T. H. Huxley, 

 LL.D., Secretary to the Royal Society. 



