On the Supposed Origin of Life in Solutions of 
Colloidal Silica. 
BY 
SYDNEY G. PAINE. 
With Plate IX. 
T HE origin of life is at present in entire obscurity, and it would seem 
that our knowledge of chemistry and physics must advance consider- 
ably before any real light can be thrown upon it. 
It is a question which lends itself more to speculation than to laboratory 
practice, but it is hoped that one day we may be in a position to investigate 
experimentally the phenomena concerned in the change from the non-living 
to the living state. 
Except for certain investigations in the first half of the nineteenth 
century, the only experimental work which definitely had as its object 
the realization of this change is that of the late Dr. Charleton Bastian. 
Since the appearance of his first publication on the subject in 1870 until the 
time of his death, Dr. Bastian held firmly to the yiew that living organisms 
may arise de novo from non-living materials. During the past twenty years 
he has supported his view by numerous experiments in which he describes 
the development of organisms under conditions calculated to exclude all 
possibility of infection by a living germ. 
The results of this work are to be found in three monographs by 
this author ( 1 ), and in the pages of Nature (2). 
The method of experiment is described fully at page 30 of ‘ The Origin 
of Life’, and consists of enclosing in special tubes very dilute solutions 
of colloidal silica mixed either with phosphoric acid or with some form 
of colloidal iron ; after sealing, the liquids are carefully sterilized by inter- 
mittent sterilization at ioo° C. or by short exposures to temperatures of 
120 0 C. to i35°C. Thus prepared, the tubes are exposed to light at 
an east window for periods varying from six months to two years. During 
this time a small deposit collects at the bottom of each tube, and the 
examination of this is made by removal with a fine pipette on to a micro- 
scope slide, or the liquid is sometimes centrifuged and the deposit 
examined microscopically. 
[Annals of Botany, Vol. XXX. No. CXIX. July, 1916.] 
