113 
A New Self-registering Anemometer and Pluviometer 
for Sydney Observatory. 
By H. ©. Russet, B.A., F.R.A.S. 
[Read before the Royal Society of N.S.W., 17 December, 1884.] 
Tue first Self-registering Anemometer and Pluviometer in Sydne ey 
Observatory was made and set to work in 1863, and, with | 
slight repairs, this instrument has done its work ever since ; but 
the wear and tear of twenty-one years has told so severely on some 
of the wheels, more particularly the one into which the screw-spindle 
of the cups works, that it became necessary either to make extensive 
repairs or a new instrument. As repairing the old one would have 
stopped the record, it was determined to have a new one made 
embodying some ideas which experience had suggested. 
may be useful to others, I have determined to explain to you the 
more important parts of the new instrumen 
Owing to the fact that the Time-ball and ‘shaft are on the only 
available tower, it was necessary from the first to elevate the vane 
and cups above them ; otherwise the wind eddying round the shaft 
affected the cups and vitiated the record ; but as this required the 
me to be e feet above the leads, there was some difficulty in 
ringing the motion down to the registering part or cylinder. In 
the old one this was effected by reducing the rate of motion of the 
turned once for 560 revolutions of the cup, or 4 miles of 
In the new anemometer, a brass box 6 x 4x3 inches is placed 
on top of a tube 3 inches in diameter, and extending 17 feet above 
the leads of the tower. Into the top of this box a piece of inch 
pport 
upper bearing of the 8-inch tube that carries the vane. The lower 
bearing of this is attached to the side of the box, and a bevel wheel 
is attached to the lower end, and gears into one of equal size on a 
h 
centre ; they work on a spindle inside the vane spindle, the top 
i ing of bone and the lower one a hardened steel cup, 
larger than the end of the screw spindle that works in it, so that 
it serves as oil-cup and bearing. This screw spindle works a wheel 
‘fifty teeth, the axis of which is a screw working into a wheel of 
