ANNIVERSARY ADDRESS. 28 
in this observatory ; all double star measures up to end of 1896 
have been published, and the next volume of meridian observations 
is now ready for the printer. Photographic work suffers more from 
drought haze than ordinary telescope work, because the hazy sky 
reflects the city light and produces fog on the plates. Mr. Russell 
has, however, obtained three hundred and sixty-eight star photo- 
graphs, with exposures of from thirty to forty-five minutes ; these 
are for the chart of the heavens, and the comparatively long 
exposures limit the number of plates which can be taken. 
As regards Meteorological work, the volume for 1895 has been 
published and that for 1896 is ready for the printer. It contains 
a series of six outline maps of New South Wales, (1890 to 1895 
inclusive), in which the rainfalls of all parts of the colony are com- 
pared with the average, and the result given as a percentage ; 
this proves to be the best method yet tried for estimating the 
value of the annual rainfall. The series has been carried back to 
1880 for publication in the 1896 volume. Another series of 
diagrams, shewing the monthly distribution of rain with special 
reference to agriculture, in the various parts of the colony, is in 
course of preparation ; some of them are ready for the 1896 volume. 
The number of volunteer observers in the country is rapidly 
increasing, and every square degree of the colony now contains 
three or more observers, some as many as ten. Amongst the 
recording instruments at the Observatory a long felt want has 
been supplied, viz., an extremely sensitive recording thermometer, 
which shows every ripple of change in the temperature wave even 
to a quarter of a degree, and shows very clearly that the atmo- 
sphere, even when there is not a cloud in the sky, is often made 
up of portions which are not equally heated. Ifa large cloud 
passes over the sun, or a shower of rain comes, the fact is wey 
recorded by the new thermometer. 
Besides the work of the Sydney Observatory, Mr. John Tebbutt 
has a record of important work during the year, carried on at his — 
Observatory, the Peninsula, Windsor, New South Wales. The 
work which Mr. Tebbutt has done since the close of last May 
