140 Tue MIcROscoPE. 
CAUTIONS IN VIEWING OBJECTS. 
Beware of determining and declaring your opinion sud- 
denly on any object; for imagination often gets the start of 
judgment, and makes people believe they see things, which 
better observations will convince them could not possibly be 
seen: therefore assert nothing till after repeated experiments 
and examinations in all lights and in all positions. 
When you employ the microscope, shake off all prejudice, 
nor harbor any favorite opinions; for, if you do, ’tis not 
unlikely fancy will betray you into error, and make you think 
you see what you would wish to see. 
Remember that truth alone is the matter you are in search 
after; and if you have been mistaken, let not vanity seduce 
you to persist in your mistake. 
Pass no judgment upon things over-extended by force, or 
contracted by dryness, or in any manner out of their natural 
state, without making suitable allowances. 
There is no advantage in examining any object with a 
greater magnifier than what shows the same distinctly; and 
therefore, if you can see it well with the third or fourth glass, 
never use the first or second; for the less a glass magnifies, the 
better light you’ll have, the easier you can manage the object, 
and the clearer it will appear. 
It is much to be doubted, whether the true colors of 
objects are to be judged of, when seen through the greatest 
magnifiers: for as the pores and interstices of an object must 
be enlarged according to the magnifying power of the glass 
made use of, and the component particles of matter must by 
the same means appear seperated many thousands of times 
farther asunder than they do to the naked eye, their reflections 
of the rays of light will probably be different, and exhibit 
different colors. And, indeed, the variety of coloring some 
objects appear dressed in, may serve as a proof of this. 
The motions of living creatures themselves, or of the fluids 
contained within them, as seen through the microscope, are 
likewise not to be determined without due consideration: for 
as the moving body and the space wherein it moves are magni- 
fied, the motion must probably be so too. And therefore, that 
rapidity, wherewith the blood seems to pass along through the 
