347 



TABLES FOR PRACTISING THE USE OF THE MICRO- 

 SCOPE AND MICROSCOPICAL MANIPULATION. 



All who desire to become practically familiar with the use of the microscope, 

 and to learn how to observe, are strongly recommended to submit to the 

 routine which a conscientious practice of the experiments given in the 

 following Tables necessarily involves. The author is fully persuaded 

 that the patient prosecution of the course recommended, for two or 

 three hours, on eight different occasions, will enable the student to 

 obtain a practical acquaintance with the elements of microscopical en- 

 quiry, which it would not be possible for him to acquire so readily by 

 reading, or indeed by any other plan. 



TABLE I. 



ARRANGEMENT OF THE INSTRUMENT FOR OBSERVATION. DRAWING 



AND MEASURING OBJECTS. 



1. Arrange the microscope for examining objects by transmitted 



light. 34, pi. X, fig. 42. 



2. Examine the objects upon the slide* with the inch, and afterwards 



with the quarter of an inch object-glasses, using first the shallow, 

 and afterwards the deep eye-piece. 4, 5, 6, pi. I, figs. 3, 4, 7. 



3. Arrange the mirror in such a manner that the rays of light may 



pass through the object in a direct course or obliquely. 10, 

 pi. V, fig. 19. 



4. Examine the same object under the quarter of an inch object- 



glass with the achromatic condenser, and afterwards without 

 the use of this instrument. 37, pi. XII, fig. 54. 



5. Draw upon paper some of the objects | on the slide. 41. 



a. Judging of the size of the paper by the eye alone. 



b. By placing the paper on a level with the stage. 



c. By measuring with a pair of compasses, p. 288. 



(1. With the aid of the neutral tint glass reflector. 44. 

 pi. XIII, fig. 60. 



* Scales from the wing of a butterfly, 

 f Tracheae from a ^caterpillar. 



