Miscellanies. 405 



and those in the fourteenth, were principally produced by the second 

 kind of induction. Although I may be too sanguine in reference to 

 ths results of this discovery, yet 1 cannot refrain from adding that it 

 appears to lead to a separation of the electrical induction of a galvan- 

 ic current from the magnetical, and that it is a step of some importance 

 towa!('s a more precise knowledge of the phenomena of magneto- 

 electricity." 



19. Ehrenherg on the Infusoria. — The following interesting conclu- 

 sions are stated in a short review, given in Charlesworth's Mag. of Nat. 

 Hist. London, Oct. 1839, of Ehrenberg's recent work, entitled Die 

 Infusions thierchen, etc. (Leipzig, folio. 64 plates.) In the Infu- 

 soria themselves, Prof. Ehrenberg has either confirmed or first estab- 

 lished a considerable number of very curious qualilies and relations, 

 which are highly interesting in a physiological and other points of 

 view, the most important of which we briefly enumerate. 



1 . Most (probably all) microscopic animalcula are highly organized 

 animals. 2. They form, according to their structure, two well-defined 

 classes. 3. Their geographical distribution in four of the parts of the 

 world follows the same laws as that of other animals. 4. They cause 

 extensive volumes of water to be colored in different ways, and occa- 

 sion a peculiar phosphorescence of the sea by the light they develop. 

 5. They form a peculiar sort of living earth; and as 41,000 millions 

 of them are often within the volume of one cubic inch, the absolute 

 number of these animalcula is certainly greater than that of all other 

 living creatures taken together ; the aggregate volume is even likely 

 to be in favor of the animalcula. 6. They possess the greatest power 

 of generation known within the range of organic nature ; one indi- 

 vidual being able to procreate many millions within a few hours' 

 time. 7. The animalcula form indestructible earths, stones, and 

 rocks by means of their siliceous testcB ; with an admixture of lime or 

 soda they may serve to prepare glass ; they may be used for making 

 floating bricks, which were previously known to the ancients ; they 

 serve as flints, as tripoli, as ochre, for manuring land, and for eating, 

 in»the shape of mountain meal, v/hich fills the stomach with a harm- 

 less stay. They are sometimes injurious by killing fish in ponds, in 

 making clear water turbid, and in creating miasma ; but that they 

 give rise to the plague, cholera morbus, and other pestilential diseases, 

 has never been shown in a credible manner. 8. As far as observation 

 goes, the animalcula never sleep. 9. They exist as Entozoa in men 

 and animals, the Spermatozoa not being taken into consideration here. 

 10. They themselves are infested with lice as well as Entozoa, and on 

 the former, again, other parasites have been observed. 11. They are, 



