244 THE AMERICAN MONTHLY [November, 



many particular long particles, and mostly with little figures like flow- 

 ers, as they are represented in the 8th fig. between k and /. This is 

 the first representation of a diatom I know of. 



In the Philosophical Transactions, No. 284, for March and April, 

 1703, is " an extract from some letters sent to Sir C. H., relating to some 

 microscopical obsei-vations communicated by Sir C. H. to the pub- 

 lisher." In the letter of Sept. 29, 1702, he says, " the end of last week 

 a buck, which by mischance had his leg bi'oke, was kill'd, tho' so late 

 in the season, and it being rutting time I thought I might, with the 

 greatest advantage, observe the semen niasculum. Not to trouble you 

 with some former attempts of this kind, as soon as he was killed I took 

 out one of the testicles with the adjoining seminal vessels^ and found 

 the vasa deferentia very turgid and full of a milky fluid. After vari- 

 ous methods of viewing this liquor, I saw the aninialca (in prodigious 

 numbers) very perfectly in several postures, moving very briskly, and 

 shew'd them to others, who own'd they appear'd as plain as tadpoles 

 to a nake i eye." He figures these spermatozoa with globular heads 

 and short :ails. 



He figvn'es the vorticella, which Leewcnhocck figures, but larger and 

 plainer, showing that he had high-power lenses, which were 

 made for him by Mr. Wilson. He also figures various other animal- 

 cules. 



In the Philosophical Transactions for September and October, 1702, 

 at page 1241, is " The Description and Manner of using a late invented 

 set of small Pocket Microscropes, made by James Wilson, which, with 

 great ease are apply'd in viewing opaque, transparent, and liquid ob- 

 jects, as the farina of the flowers of plants, etc. The animalcula •• in 

 semine, etc." In this he describes and figures the microscope 

 of eight separate " magnifying glasses," in which he follows 

 the " authority of the excellent Dr. Hook," who " assures us that single 

 magnifying glasses (when they can be used) are prefei'able to micro- 

 scopes composed of two or more magnifying glasses." He also figures 

 the down from a butterfly's wing, the "farina" of maloe, tail of a 

 fish with the veins and arteries in it, two animalcules on the tail of the 

 fish, and " one of the lice fovmd on the beetle, called Scarahcns pedicu- 

 losus^ 



But to return to the " gentleman in the country." He mentions the 

 small plant as figured by Leewenha^ck as " Lens palustris or Duck 

 meat^ which is Lemna" and "• the Animalcula^ which Mr. L. describes 

 sticking to the root of the plant," which is Hydra fusca^ but says he 

 " was never so fortunate as to see that motion in them, which he says 

 is like that of a mill-wheel." '• But I think I can easily account for this 

 mistake of Mr. L., or rather of his painter, for in the §ame water 

 wherein I have seen these plants and animalcula ^ I have observed 

 a small, round creatui'e, whose many legs stand like radii all about 

 its body. This has a swift, progressive motion, but will often lie still 

 (when only you can perceive those radii) , and then turn very swiftly 

 round like a wheel, sometimes one way, and then stop and turn the 

 other way, without stirring an hair's bi^eadth forwards. Now, 'tis 

 very probable that one of these might show its tricks so very near or 

 among a tuft of the other fixed Animalcula, that it might be very well 

 taken for part of the same, and I am very confident that this is a matter 



