92 naturalists' assistant. 



Lieberkuhns, parabolas, etc., etc., are but rarely used by the 

 true student and need not be described here. 



This is a good place to say a word about the "Novelty," 

 " Globe," "Craig," and other microscopes which are extensive- 

 ly advertised and as extensively recommended by clergymen, 

 teachers, and others. These microscopes, furnished for twen- 

 ty-five cents, are said to magnify 10,000 times, to show 

 animalcules in water and various other wonderful things, but 

 they are merely catch-pennies, and the clergy who recommend 

 such worthless instruments are entering a field in which they 

 are perfect ignoramuses. These cheap microscopes are 

 poorly made, give distorted and misleading images, and in a 

 word are worse than useless. The Craig is perhaps the worst 

 of the lot. 



DIFFERENT FORMS OF MICROSCOPES. 



From the days of Adams, Baker, Trembley, and the older 

 investigators, microscopes have been used extensively by 

 naturalists, and of course in these years various styles of in- 

 struments have originated, but all forms now manufactured 

 may be roughly classified under two heads, the English and 

 the Continental patterns. The latter are almost always 

 small, of great simplicity, and those of the prominent 

 makers like Zeiss, Hartnack, Merz, or Nachet, are invariably 

 of good workmanship. These have either a circular or horse- 

 shoe base from which arises the support of the working por- 

 tions of the instrument. The stage is almost invariably of 



