Aucust 17, 18y9] 
NATURE 
Sih 
Colombia, presented by Mr. R. E. Stone; two Common 
Duikers (Cephalophus grimmi), six Swainson’s Francolins 
(Plernistes swainsonz) from South Africa, presented by Mr. J. 
E. Matcham; a Suricate (Suricata tetradactyla) from South 
Africa, a Common Hamster (Albino) (Cricetus frumentarius), 
European; an Antillean Boa (Boa diviniloque) from the West 
Indies, deposited; two Spotted Turtle Doves (Turtur sur- 
atensis), bred in the Gardens. 
OUR ASTRONOMICAL COLUMN. 
Homes’ Comet 1899 a (1892 III.). 
Ephemeris for 12h. Greenwich Mean Time. 
1899. R.A Decl. Br. 
h. ms. Ope ee re? (va)-2 
August 17 250 17:17 +36 29 5374 
18 52 16°44 36 45 243 
19 53 14 43 37 0 51°8 
20 54 I1‘12 37 16 15°8 o1905 0'04889 
21 55 6°48 37 31 363 
22 56 047 37 46 532 
23 56 53°06 BSezi 653 
24 257 4422 +3817 157 01888 0704999 
MorioNn oF APSE LINE OF a GEMINORUM.—In a previous 
communication to the Afem. Soc. Degli Spett. Ital. (vol. xxvi., 
1897), M. A. Belopolsky has drawn attention to the rapid 
motion of the line of apsides in the system of a Geminorum 
(Castor), and now, in the last issue of the same journal 
(vol. xxviii. pp. 103-108, 1899), he gives the results of more 
recent work on this interesting double star. The former 
measures were obtained from a series of spectrographs obtained 
at Pulkowa during one year, and were not sufficiently repre- 
sentative to give certain results. He has now at his disposal 
observations which he has made during the past three years, and 
in the present paper confines himself to the examination of three 
groups of these observations, reserving the discussion of the 
whole for a later article. These groups of observations embrace 
the periods: (1) 1896, March 8 to April 26; (2) 1898, March 
15 to May 2; (3) 1899, January 19 to April 16. In the calcu- 
lation several difficulties are found, the chief of which are the 
rapid movement (period 2°93 days), the uncertainty of a few 
thousandths of the period producing an error of several degrees 
in the true anomaly, and also the uncertainty of the time of 
passage through Periastron. 
Tables are given showing comparisons between the calculated 
and observed values for the velocity in the line of sight, for all the 
dates in the three groups of observations, from which the author 
concludes that the probable error is only about + 0°368 l.g. 
(+ 0°92 miles), He finally concludes that the observed rapid 
movement of the line of apsides is real, and that the ferzod of 
this revolution is 
4 years 40 days = 2100 days. 
He attributes the cause of this to the probable flattening of the 
components, and mentions that a flattening of one-seventh 
would be sufficient, if the dimensions of the system are equal to 
those of Algol, to produce the observed motion. 
Mr. TEBBUTT’S OBSERVATORY.—In presenting his report of 
the work done at his observatory at Windsor, New South Wales, 
during the year 1898, Mr. John Tebbutt states that the past 
year was remarkable for the large number of clear nights during 
the autumn, winter and spring months, rendering it possible to 
get a large amount of work done. 
Meridian work was carried out with a 3-inch Cooke transit, 
the timekeeper being a Poole 8-day chronometer. 
Extra-meridian work consisted of observations of occultations, 
planets, and comets. With the 8-inch equatorial thirty-six dis- 
appearances at the moon’s dark limb were measured and the 
results published. The same instrument, in conjunction with 
the Grubb filar micrometer, was employed on fifty-seven nights 
in planetary observation ; 73 comparisons of Vesta, 211 of Iris, 
107 of Isis, 91 of Jupiter and 7 Virginis, 132 of Uranus and 
w! Scorpii, and 132 of Uranus and w? Scorpii, were recorded ; 
and comparisons with the measures published by other observers 
have proved to be very satisfactory. 
NO. 1555, VOL. 60| 
The observations of comets have been made with~both the 
44-inch and 8-inch equatorials, and have included measures of 
Encke’s Comet, and Comet Coddington- Pauly, the latter being 
followed from June 15 to March 3, 764 measures of the comet 
and 138 of comparison stars being made on 103 nights during that 
period. 
Attempts to observe Comets Perrine, e and /, 1898, were un- 
successful owing to their proximity to the sun. 
All the observations, computations and reductions have been 
made by the proprietor of the observatory, it being extremely 
difficult to obtain even occasional assistance. 
TEMPERATURES IN GAsEouS NEBUL&.—Mr. F. E. Nipher, 
in a paper read before the Academy of Science, St Louis 
(vol. ix., No. 4), discussed the conditions of temperature, &c., 
in a gravitating nebula having w7zform temperature throughout 
its mass. In a second paper he now discusses the same 
subject on the different assumption that the initial temper- 
ature d2mznishes from the centre outwards. After a lengthy 
mathematical discussion he derives a general formula 
ry) \1=n 
D=Tp (1 +n)(“) 
= 
which reduces to Ritter’s equation if the temperature of the 
mass be assumed initially uniform. He concludes that in 
general the temperature throughout a nebula is to be given in 
terms of the coordinates of the point in space where the 
temperature is to be determined, and the ratio of contraction 
from any given initial condition. If the temperature remains 
constant throughout the mass, then Ritter’s equation would 
hold during contraction. If on account of unequal perme- 
ability to heat the temperature should become unequal, 
the law of temperature change asa function of the ratio of 
contraction becomes more complex, so that if at any time the 
temperature varies inversely as the #th power of the distance 
from the centre, the ratio of temperature change at any con- 
tracting surface will be given by the above equation, in which 
it is evident, from physical conditions, that #2 cannot be less 
than zero. 
THE RECENT PERSEID METEORIC SHOWER. 
A SERIES of very clear nights enabled the Perseids to be 
well observed this year. The shower was not of unusual 
brilliancy, but it furnished a considerable number of meteors, 
and they appear to have been widely observed. The occurrence 
of the Perseid display now excites not only the attention of the 
meteoric enthusiast, but is seriously observed by astronomers 
generally, and the application of photography to work of this 
kind has greatly stimulated the interest in it. 
On August 9 the writer watched the north-eastern sky be- 
tween about 10h. 15m. and 13h., but a few clouds prevailed 
during the first hour. 38 meteors were seen, of which 26 were 
Perseids. On August 10, between about 1oh. and 13h. 30m., 
QI meteors were seen, of which 72 were Perseids. On August 
11, between 1oh. and 13h. 30m., 90 meteors were observed, in- 
cluding 68 Perseids. On August 12, between 1oh. and 13h. 
30m., 62 meteors were counted, and amongst these were 43 
Perseids. On August 13, 23 meteors (10 Perseids) were seen 
in 2 hours, and on August 14, 29 meteors (12 Perseids) were 
recorded in 24 hours. 
On August 10, between 11h. rom. and 14h. 35m., Prof. A. S. 
Herschel at Slough observed 104 meteors, and after making 
allowance for time spent in registering the paths the horary 
number of meteors for one observer would be about 40. He 
describes the maximum as having been observed between 12h. 
and 12h. 30m., when several bright meteors succeeded each 
other at short intervals. 
On August ro Mr. T. H. Astbury, observing at Shifnal, Salop, 
says that thirty-four meteors were seen between 1oh. and 1th., 
the great majority being Perseids. There was also an active 
radiant in Cygnus. 
On August 11 only about eighteen meteors were seen from 
toh. till rrh., so that he concluded the maximum occurred on 
the roth, when the meteors were brighter and more numerous. 
According to the Bristol observations already alluded to, very 
little decline in numbers was, however, noticed on August 11, 
and to exhibit this more readily, the following table has been 
compiled :— 
