
- seded by those of Brown. 
Jone 9, 1923] 
NA TURE 
789 

é 
5 
The Royal Observatory, Greenwich. 
ANNUAL VISITATION. 
THE visitation of the Royal Observatory took 
place on Saturday afternoon, June 2. In 
addition to members of the Board of Visitors a large 
number of guests interested in astronomy were 
present, and took part in the inspection of the 
observatory and instruments. 
The astrographic equatorial has been remounted 
on its return from Christmas Island, and the instru- 
ments left in Russia in 1914 have just arrived safely 
after an absence of nearly nine years. The Astro- 
nomer Royal in his report expresses his regret at the 
failure of the Christmas Island expedition ; he notes, 
however, that the close verification of the Einstein 
shift by the Lick Observatory expedition renders it 
unnecessary to send an expedition from Greenwich 
to observe the Californian eclipse next September. 
The exchange of wireless signals has reopened the 
uestion of the small differences of time-determina- 
tions at different observatories. Examination of the 
bearings of the transit circle showed that the western 
pivot was bearing only on its eastern edge ; this was 
remedied by a slight lowering of the bearing. The 
test was made by placing some rouge on the bearings, 
then lowering and rotating the instrument; the 
presence or absence of rouge on the pivot showed 
where it was in contact with the bearing. 
The results of the wireless time comparisons for 
the year are given; the annual means are Paris 
+o-10 sec. ; Bordeaux +0-14 sec. ; Nauen 0-00 sec. ; 
Annapolis (August to December only) +0-03 sec. 
The plus sign means that the other station is late on 
Greenwich. In the case of Annapolis, the discord- 
ance is wholly explicable by the time of transmission ; 
0-06 sec. of the Paris and Bordeaux discordances is 
due to the fact that Leverrier’s Tables of the Sun, 
used in France, differ by this amount from those of 
Newcomb. In the long run these differences will 
probably give excellent determinations of longitude. 
Observations of the moon are dealt with in special 
detail in the present report, on account of the fact 
that Hansen’s tables, used in the ‘‘ Nautical Almanac”’ 
from 1862 to the end of 1922, have now been super- 
This was, therefore, 
selected as a suitable occasion for collecting all the 
Greenwich observations of the moon made since the 
time of Bradley, and reducing them to Brown’s 
system (modified by using Fotheringham’s secular 
acceleration, which is 4-79” in excess of Brown’s). 
It was then found that the residuals could be repre- 
sented by two empirical terms, one with amplitude 
3” and period 70 years, the other with amplitude 1}” 
‘and period 59 years. The two terms are now in 
unison, producing a large oscillation, but in Bradley's 
time they tended to neutralise each other. A full 
comparison is given between Brown’s Tables and 
observation for the first quarter of 1923; there isa 
nearly constant error in longitude of -—7-8”, about 
half of which is due to Brown’s use of too small an 
acceleration. 
_ Observations with the Cookson floating telescope, 
lent by Cambridge Observatory, are being continued. 
Mr. Jones has revised his determinations of latitude 
Variation with this instrument; and they are in 
satisfactory accord with those made elsewhere. One 
of the seven-year maxima of latitude variation is due 
about 1923. The 28-inch equatorial is being used for 
observation of close and difficult pairs; 66 pairs 
with separation less than 0-5”, and 105 between 0-5” 
and 1:0” have been observed during the year. Mr. 
ackson is continuing to deduce hypothetical paral- 
xes for these and other stars. 
_ The 26-inch refractor is being used for photographic 
determinations of stellar parallax; 49 parallaxes 
have been determined during the year, making a 
total of 195 with the instrument. The 30-inch 
teflector is being used for photography of stellar 
spectra with a combination of prism and grating. 
A principal spectrum is thus obtained, bordered by 
diffraction spectra of known relative intensities, thus 
determining the density gradient of the plate for all 
wave-lengths. With the astrographic equatorial 
some of the fields photographed about twenty years 
ago are being re-photographed through the glass, so 
that superposition on the earlier plates, film to film, 
enables proper motions to be deduced. The work 
has begun with zone 65° N. Declination, and will 
gradually approach the pole. 
- Sunspot activity continues to decline. 
i 
There was, 
however, a considerable group of spots visible from 
December 22 until January 4 in latitude 6° N. A 
high-latitude spot in 41° S. was photographed on 
November 14 and 15. 
The following are the provisional magnetic ele- 
ments deduced for 1922 : 
Declination 13° 46-6’ W., Dip 66° 51-9’, Hor. Force 
018449, Vert. Force 0-43181 (the last two being in 
C.G.S. units). 
The weather report is for the twelve months ending 
April 30, 1923. The mean temperature was 49°8° F., 
being 0-2° above the average. On two days, both in 
May, the temperature reached go° F. It fell to 
freezing-point on 21 days. There were 1404 hours 
of bright sunshine, 31-5 per cent. of the possible 
amount. . 
The Astronomer Royal naturally refers to the 
‘severe loss which the Observatory has sustained in 
the death of Mr. W. W. Bryant, noting his enthusiasm 
in former years as a meridian and double-star observer, 
and the zeal and energy with which he afterwards 
carried on the work of the Magnetic and Meteorological 
Department. Allusion is also made to the astro- 
nomers who have visited the observatory for special 
purposes during the year; they include Mr. Dodwell, 
director of Adelaide Observatory, Messrs. Comrie and 
Greaves from Cambridge, and Mr. S. Gaythorpe, who 
came to study the Horrocks MSS. in connexion with 
a biography of Horrocks which he is preparing. 
As C.D: C. 
Royal Visit to University College and Hospital, London. 
‘Bai Thursday, May 31, the King, who was accom- 
panied by the Queen, opened the new Institute 
of Anatomy at University College, London, and laid 
the foundation-stone of the new Obstetric Hospital. 
Her Majesty laid the foundation-stone of a Nurses’ 
Home which is to be erected on an adjacent site in 
connexion with University College Hospital. 
Before a gathering’as brilliantly representative of 
the science and practice of medicine as of philan- 
thropy and affairs, his Majesty said there could be 
NO. 2797, VOL. IIT] 
but few instances on record in which any foundation 
had received 1,200,000/. from a single benefactor in 
a single gift. The magnificent generosity of the 
Rockefeller Trustees is the more impressive since 
it was bestowed by a citizen of the United States of 
America upon a college and hospital in London, and 
thus upon the people of Great Britain and the Empire. 
The declared purpose of the trustees is ‘‘ to promote 
the well-being of mankind throughout the world.” 
‘That they should have selected the University of 
