the Deflections of the needle of a Galvanometer. 273 
placed an inch or an inch and a half objective. On the screen 
we have the graduations asa series of bright lines on a dark 
ground, and along them moves the bright index line of the 
pointer. 
the shade on its base; and by turning the transverse wire so 
that it points toward the screen, when the needles of the gal- 
easure before our college c 
December 31st, 1872. 
