388 Address of Professor Husley. ° 
the so-called Infusorial Animalcules, none of which can be seen, 
except by the aid of the microscope; while a large proportion 
belong to the category of smallest things of which | have 
spoken, and which must have all looked like mere my and 
ees under the ordinary microscopes of the eighteenth century. 
by various theoretical considerations which I cannot now 
Sonia ut which looked promising enough in the lights of that 
day, Buffon and Needham doubted the applicability of Redi’s 
hypothesis to the infusorial animalcules, and Needham very 
pee endeavored to put the question to an experimental 
s mself, if these infusorial animalcules come 
ras germs, their germs must exist either in the substance in- 
in the water in which the infusion is made, or in the 
superna air. Now the vitality of all germs is destroyed by 
heat. Therefore, if I boil the mfusion, cork it up carefully, 
cementing the cork over with mastic, and then heat the whole 
ap. vessel by heaping hot ashes over it, I must needs kill whatever 
"germs are present. Consequently, if Redi’s hypothesis hold 
_- good, when the fusion is taken away and allowed to cool, no 
~~ animalcules ought to be developed in it ; whereas, if the animal- 
ez. are not de ndent on its spe germs ones are ere 
TT EE eT ee eS ee Pee 
allow for their gee 
In much of his work Needham was associated with Buffon, 
and the results of their eM fitted in admirably with 
the great French nat s hypothesis of “ organic molecules,” 
according to which, life is the mdefeasible property of certain 
indestructible molecules of matter, which exist in all living 
things, and have inherent activities by which they are distin- 
guished from not living matter. Hach individual aioe! organ- 
ism is formed by their temporary combination. They stand to 
it in the relation of the particles of water to a seh or a | 
whirlpool; or to a mould, into which the water is poured. The 
form of the organism is thus determined by the reaction be- 
tween external conditions and the inherent activities of the 
organic molecules of which it is composed ; and, as the stop- 
page of the whirlpool sage nothing but a form, and leaves 
the molecules of the water, with 
so what we call the death and putrefraction of an animal, or of 
a ita is merely the breaking up of the form, or manner of 
association, of its constituent organic molecules, which are then 
set f - as infusorial animalcules. 
Tt will be perceived that this doctrine is by no means identi- 
eal with Abiogenesi with which it is often confounded. On 
