30 



THE MICROSCOPE AND ITS LESSONS. 



showed him the wonderful feet, with their booklets and 

 suckers, and he was more astonished than before. Singu- 

 larly illustrative of the impression made upon the mind 

 by only one well-used opportunity of witnessing some of 



the objects in "the In- 

 visible World," let me 

 amuse the reader with 

 one result of my friend's 

 experience. Many years 

 afterwards he told me of 

 a dream he had, in which 

 there may be more 

 matter for consideration 

 than I must impose upon 

 the reader. My friend's 

 dream was this. He had 

 gone home to dinner on 

 his fiftieth birthday, and 

 after it was over, seated 

 in the conservatory smok- 

 ing his pipe, one of his 

 daughters, climbing up- 

 on his shoulder, caused 

 the tobacco - smoke to 

 get into his eyes, while 

 she remarked, " She did 

 not know another man 

 who, at his age, had so 

 few grey hairs." In the 

 course of the evening my name occurred in the conversa- 

 tion, which after the exhibition just mentioned, namely, 

 the wonders of a house-fly my friend always associated 

 with the microscope. And these four things, namely, the 

 smoke, the grey hairs, the instrument, and myself, all got 



Tongue of the house-fly (Musca 



domestica). 



a, terminal sucking disc; &, aperture leading to 

 gullet ; c, lancets ; d, trachea ; e, maxillary 

 palpi. 



