20 
President’s Address. 
this survey is being laid down to a half inch scale in 
“’divisions” containing one square degree, of which there 
are thirty-one contained in the Colony. 
Another great scientific work carried on by a Government 
department, under the direction of a member of the Council 
of our Society, is Mr. Selwyn’s Geological Survey of Victoria, 
— a work of which this colony may well be proud, and which 
cannot fail to be of the highest advantage in all future time 
to the colonists engaged in undertakings requiring a know- 
ledge of the structure and composition of the earth, and 
the distribution of the mineral riches of the country. 
From personal experience of the British Geological Survey, 
in which I at one time took part myself, I can confidently 
affirm, that the Geological Maps issued by the Victoria 
Survey, are equal to any in the world, and superior to most 
works of the kind which have been published, in the admi- 
rable accuracy of their detail ; although the great additional 
labour and delay has been thrown on the department of 
making a great portion of the topographical map, and nearly 
all the physical feature-shading required as a basis on which 
to plot the proper geological work. 
During the last twelve months, the field geologists have 
mapped an area of about four hundred square miles, a 
great portion of which, being more or less auriferous country, 
has required that the physical features should be minutely 
laid down : these include gullies, quartz reefs, igneous dykes, 
and the contouring of hills. This makes about 3,500 square 
miles of the Colony now geologically mapped. The staff 
engaged in this work has consisted of three field geologists, 
one assistant field geologist, and nine men. The districts in 
which they have been at work during the past year are 
Yandoit, Pentland Hills, Ballan, and the Campaspe, north 
of Barfold. Besides this regular and progressive work, the 
auriferous and argentiferous reefs of St. Arnaud have been 
carefully examined, as well as the processes in use there for 
treating the silver ores for the extraction of the silver, and 
a detailed report on the same by one of the staff, Mr. Ulrich, 
is nearly completed. The quartz reefs at Wood’s Point have 
been also visited and reported on. 
Amongst the more interesting points of discovery by 
the Survey during the year, is the occurrence of an 
auriferous drift resting on basalt, and overlaid by a 
subsequent flow of the same rock. This was met 
