ZOOLOG 1’ AND BOTANY, MIOliOSCOl’Y, ETC. 
97 
Most finders labour under two disadvantages, viz. (1) inadjustability 
to different Microscopes for comparison purposes, owing to variations in 
stand and objective construction ; (2) unreliability, even on tbe same 
Microscope, owing to the difficulty of securing a precisely similar ad- 
justment. The authors’ object is to obtain an absolute means of recording 
the position of any part of a preparation, and one which shall moreover 
be independent of any particular make of Microscope. 
They propose to indicate such a position by means of co-ordinates 
measured parallel to the top and left-hand edges of the slide, and every 
adjustable stage lends itself to such measurements. The readings of 
the scales should be so altered that the indicator is at zero when the 
left edge of the slide is in the centre of the field of view. If any instru- 
ment does not haj>pen to give zero under these circumstances, the reading 
should be carefully noted once for all and subtracted from the actual 
reading of any required point in the preparation. This will give one 
co-ordinatf>, and the other can be ascertained similarly. A simplification 
would be introduced if the scales were made movable for adjustment in 
the direction of their long axis. The figure (fig. 16) will make the 
authors’ arrangements clear. 
Microscopist’s Table. — This piece of furniture (fig. 17), designed by 
Messrs. Bausch and Lomb, has a revolving top and vertical adjustments. 
It is made of solid quartered oak with japanned iron base. The top is 
Fig. 17. 
76 cm. in diameter, and has three drawers with brass handles. The 
table may be raised and lowered as desired from 79 cm. to 112 cm., and 
clamped in position by a heavy band clamp, the adjusting bar being 
3 cm. in diameter. The table is equally as stable as if supported on four 
1899 H 
