EHRENBERG ON ORGANIC MOLECULES AND ATOMS. 573 



tlie above-mentioned process with colouring nutritive substances, and 

 which possessed voluntary motions, but the entire and greatest dia- 

 meter of whose body only amounted to the yjoo ^^ 2 00 ^^ ^ Parisian 

 line*. The smallest animal form, to Avhich I have given the name of 

 Monas Tcrmo, is the same being as that which Otto Fr. Miiller has 

 delineated among the infusoria. I could perceive in the greatest indi- 

 viduals of this animal form as many as six, and in the smallest as 

 many as four, internal sacs coloured by blue indigo, which at times did 

 not occupy quite half of the dimension of the animal. Such a sac 

 therefore of the Monas Termo, if the animalcule measures yj^ 

 of a line, and if we suppose only four sacs occupying the half of it 

 (therefore not one of the smallest), is xg^^jy of a lin. in size, which is 

 five times smaller than the minutest particles obsen-ed by Brown. At 

 the upper part of this animal is perceived, as in all the monads, a 

 powerful pushing aside of particles still smaller than themselves, when 

 these come near to them ; and it is therefore probable that they have 

 a fringe of ten to twenty cilia near the anterior part of the mouth aper- 

 ture, as in Blonas Pulvisculus, and especially in the other still larger 

 monads. Further, if even we suppose the single colouring particles 

 with which the bellies are gradually filled not to be numei'ous, it would 

 be against all probability not to think that they were filled by several 

 particles. Let us however only suppose each sac to be filled by three 

 colourmg atoms, — which from the roundness made perceptible by the 

 motion communicated to them we may well admit, — this alone aftbrds 

 a proof of the existence of material colouring particles of red and dark 

 blue moving fi'eely in water, Avhich measure 3 ^ ^ ^ ^ of a line, or 432W0 

 of an inch, in diameter ; and calculating these objects from the smallest 

 of the animalcules, which by actual observation were found to be goW 

 of a line in size, and which sometimes contained four coloured points 

 in the hinder part of the body, these particles, which cannot be dis- 

 tinguished individually by the eye with a magnifying power of 800, 

 but yet are to be recognised as corporeal, would amount to xah'iJo ^^ ^ 

 line, or jttj'qoo ^^ ^^ inch, which exceeds the molecules of Brown 

 nearly twenty times in smallness. 



The above-mentioned transparent cilia about the mouth of these mo- 

 nads (perceivable only by their action) may also approach in fineness 

 those just cited; for if they were not less than 53^00 of a line, or the 

 nmltipleof forty-eight, with my magnifying power of 800, there would be 

 no optical reason, except their transparency, why I should not see them 

 with that power, as will be evident from the sequel of the memoir. I 

 shall moreover direct attention to the fineness of other parts of these 

 organic living beings. The smaller monad-bellies are seen isolated in 



• 1 have already mentioned tliat 1 make use of a glass micrometer which 

 measures -r-oiDTr of an inch. 



