162 EVENINGS AT THE MICEOSCOPE. 



but vibrations, even when so violent as those produced 

 by tapping the stage of tlie microscope with the finger- 

 nail, have no effect unless the stalk be tense, its own 

 power of vibration being then only developed, just as 

 a cord becomes musical in the ratio of its tension. 



It is not until wc view these creatures with a good 

 microscope that we acquire an adequate idea of their 

 beauty : for myself, at least, it was so. I had seen en- 

 gravings of many of the invisible animalcules, and had 

 read technical descriptions ; but of their brilliant trans- 

 parency, their sudden and sprightly motions, their gen- 

 eral elegance and delicacy, and the apparent intelli- 

 gence with which they are endowed, neither books nor 

 engravings had given me any conception. 



Some of the individuals under our present exam- 

 ination are exhibiting phenomena of no less interest 

 than their form and motions. Some of the stalks are 

 terminated by two vases instead of one, which appear 

 to spring from a common point. These, however, are 

 the result of the spontaneous splitting of one ; and in 

 other examples you may see the process in different 

 stages, or, if your patience endure a couple of hours' 

 watching, you may trace the whole phenomena, as I 

 have done, from the moment when it first becomes re- 

 cognisable, to its completion in the freedom of one of 

 the newly formed animalcules. 



For instance, you perceive that one of the bells 

 instead of being vase-shaped, has assumed a globular 

 form. By keeping your eye on this for only a few 

 moments, you detect a depression forming in the midst 

 of its front outline, which momentarily deepens, nntil 

 it is manifestly a cleft. The division proceeds down- 

 wards, the two halves herding simultaneously, so that 



