i88o/ 
Scientific Progress of the Past Year. 
17 
the Astronomical (as distinguished from the Photographic) 
Observations and Results for Printing is complete for the 
expeditions to the Hawaiian Islands, Rodriguez Island, and 
New Zealand. For the other two expeditions much remains 
to be done— chiefly, however, mere copying. The employ- 
ment of the staff upon the measurement, re-measurement, 
and discussion of the photographs, was the most serious 
cause of the delay that has occurred in presenting to the 
public the astronomical results. Those who are now 
engaged upon this subject entertain serious doubts as to 
whether any result of value, as regards the special objeft of 
the expeditions, is to be expected from the photographs, 
owing to a want of sharpness in the images. Some of the 
photographs taken by the Russian Astronomers have been 
measured, but not very successfully. The telescopic obser- 
vations of the internal contadts, at many stations m India 
and Australia, as well as at those occupied by the Govern- 
ment Observers, in all thirty-one observations of the Ingress 
and forty-eight of the Egress, have yielded a value of the 
mean solar parallax of 8" - 85+o '*03.+ ... 
The Greenwich Nine-Year Catalogue of 2263 stars with 
discussions of the systematic errors of R-A. s and N.P.D. s 
has been published. 
The complete redudtion of the measures of about 1900 
photographs of the sun, taken at Greenwich from 1873 up to 
the present time, affords data immediately aval able for 
determining the distribution of spots and faculae on the sun s 
surface, and the position of its axis of rotation The photo- 
graphs now regularly taken at.Greenwich may be consideied 
a continuation of the Kew series.. ,• 
The reduction of the Greenwich magnetic obseivations, 
l8 , 1 _ I 877, has afforded an opportunity for testing the con- 
nexion (first suggested by Sir E. Sabine and. afterwards 
investigated as regards the element of declination by Pro- 
fessor R. Wolf) between magnetic variations and sun-spots. 
Mr. Ellis has compared the diurnal ranges of magnetic 
declination and horizontal force with Professor Wolf s curve 
of sun-spot frequency, with the result that not only is there 
a general correspondence in the two sets of phenomena, but 
the minor irregularities of the sun-spot curve are reproduced 
in the curves of diurnal magnetic range for both elements 
and further that the well-marked annual inequality in the 
latter is itself variable, being greatest at the time of maxi- 
mum of sun-spots and least at that of minimum. 
* At Haven Possuit. 
•j- “ Monthly Notices, R.A.S., 1 xxxvm., p. 455. 
VOL II. (THIRD SERIES). C 
