216 THE NORTHERN MICROSCOPIST. 
done with cheap instruments—to much of this we concur if allowed 
to ask the quality of that work, or the powers used ; it is one thing 
to work at mosses with a small and light stand, using the two-inch 
or one-inch objective, and another to be able to investigate subjects 
requiring the use of high powers, say from the jinch upwards. 
The writer’s experience is, that for the practical microscopist, it 
is absolutely necessary to be provided with a “knockabout” 
Fig. 44. . 
microscope for the purposes already mentioned: one which may be 
used with powers up to the halfinch or occasionally with the 
quarter-inch ; but if it be wished to use objectives of higher 
amplification than this, he would certainly recommend the best 
stand obtainable. 
It is not in this latter direction, however, that we expect to be of 
any use to our readers—the cheaper instruments already mentioned 
are generally made with tubes to take the continental eye-pieces, 
which being of small diameter the field is limited in size; then, 
