90. 
a) For large stands (I, I'\ photo-niicrograpliic stand) 
b) For mediuni stands (11", IV, \) 
With Micro-burner M. 7.— more. 
Turn-Table on wood base for ringing specimens 
^Attachable mechanical Stage. (Fig. 46.) 
This mechanical stage may be readily attached by any one 
to stands I, IP, IV, V and "Babuchin" stand. 
It is in principle similar to those designed by Mr. Mayall 
and Herr Reichert. Two sliding pieces mounted at right angles 
to one another after the manner of a lathe slide-rest are moved 
by means of two milled heads S, T (the rotation of S effecting 
by rack and pinion the forward and backward motion, that of T 
the lateral movements). These sliding pieces pass along millimeter 
scales which serve to record their position at any desired move- 
ment'''). The object slide is so placed as to firmly rest against 
the arm A on the left and against the projecting pin on the 
right. Then the clamping arc D is turned to the left so as to 
firmly hold the slide in its position and is fixed by means of the 
left handed screw head E. To release the slide it is sufficient 
to turn the clamping arc in the opposite direction. The object- 
slide always remains in immediate contact with the stage of the 
microscope-stand, which is imperative if the illuminating apparatus 
is to exercise its full efficiency. The slide may have any size 
between 48 and 87 mm length, 24 and 37 mm width .... 
*) The amount of the rack and pinion movement is 30 mm, that of the lateral 
movement 50 mm; the reading is taken with the aid of a simple index; but 0.1 mm 
may be estimated with ease. 
