January 22, 1914] 
LETTERS TO THE EDITOR. 
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The Present-day Occurrence of Spontaneous 
Generation. 
As is well known, Dr. Charlton Bastian has for 
several decades been investigating the occurrence of 
spontaneous generation—the development of living 
organisms from non-living matter. owever opposed 
to what seems to be our common experience this may 
be, its occurrence at some time or other is at least 
suggested by modern doctrines of evolution. Dr. 
Bastian makes use of solutions containing colloidal 
matter, from which, if it has done so, living matter 
may be presumed most probably to have sprung. 
Although such solutions apparently contain no carbon 
and other constituent elements of protoplasm, an 
ample sufficiency of such elements to supply all re- 
quirements is present as ‘‘impurities” in the solu- 
tions. 
I have carried out some experiments similar to 
those of Dr. Bastian, and although I have not yet 
been able in my laboratory to confirm Dr. Bastian’s 
observations, I have obtained no evidence to prove 
that his are erroneous. I have on several occasions 
prepared the solutions, sealed them up in tubes, and 
submitted these to a single boiling. Before sterilisa- 
tion, subcultures from the solutions have yielded 
abundant growths of micro-organisms, but after the 
single boiling I have never obtained growths on sub- 
culturing. This suggests that the three boilings to 
which the tubes are commonly subjected does kill all 
organisms present in them. I have, moreover, never 
once obtained the common forms of sporing bacilli 
from the sterilised tubes; had sterilisation been in- 
complete, these organisms would certainly have been 
expected. C 
The structures resembling organisms seen on many 
occasions in Dr. Bastian’s tubes are, I am convinced, 
really organisms, and are not artefacts,’ pseudo- 
organisms, &c.; whether they be living or no cannot, 
of course, be determined microscopically, unless they 
be motile, which has been the case on two or three 
occasions (bacteria). Dr. Bastian has drawn up the 
following statement in order that his latest results 
may be brought before the scientific world. 
R. T. Hewterr. 
Experimental Data in Evidence of the Present-day 
Occurrence of Spontaneous Generation. 
In the autumn of 1905 I found that microbes would 
grow and slowly multiply when inoculated into a 
weak solution of neutral ammonic tartrate in distilled 
water, and that though the organisms would grow 
in this solution without the aid of light, that light 
distinctly favoured the process, since when -an 
inoculated solution was equally divided, the half which 
was left exposed to ordinary diffuse daylight became 
turbid much more quickly than the other half which 
had been placed within a dark incubator, even though 
the temperature of this latter was as much as 20° F. 
higher than that of the portion exposed to daylight. 
This was an experience in opposition with previous 
bacteriological doctrine, and it has been found to be 
of much importance in connection with experiments 
which I soon after commenced, and have ever since 
1 See Anowledge, August, 1905, p. 199. 
NO. 2308, VOL. 92] 
NATURE 
eee | 
been continuing, bearing upon the question of the 
origin of life.? 
Nature of the Experimental Solutions. 
My first experiments were made with ordinary com- 
mercial sodium silicate (water-glass) diluted with an 
equal quantity of distilled water: a few drops of this 
fluid, varying from 1-8, being added to an ounce of 
distilled water containing six drops of dilute phos- 
phoric acid and six grains of ammonium phosphate, 
or else to an ounce of distilled water containing simply 
eight drops of liq. ferri pernitratis of the British 
Pharmacopeeia. 
These solutions at first, and up to the summer of 
Igio, were the two experimental fluids always made 
use of, varying only in the number of drops of the 
dilute sodium silicate employed, in accordance with 
varying strengths of different samples of this product. 
These solutions of water-glass have been found to 
deteriorate and undergo some slow changes (a rather 
copious white deposit gradually forms in the bottle 
in which they are kept), and after about eighteen 
months my solutions would no longer yield the same 
kind of experimental results as at first. Moreover, 
during the last twelve months I have been unable to 
obtain any satisfactory sample of water-glass.* 
Strangely enough, Kahlbaum’s to per cent. solution 
| of sodium silicate, which is a comparatively uniform 
product, has never yielded any satisfactory results 
when it has been used in the preparation of my solu- 
tions, 
On mentioning these troubles in the summer of 1910 
to Dr. Otto Rosenheim, of King’s College, he kindly 
gave me some of a very dilute solution of colloidal 
silica, prepared with great care after Graham’s 
method, and made with the aid of the 10 per cent. 
solution of sodium silicate above referred to, the use 
of which had hitherto always proved unproductive. 
This solution of colloidal silica gave more uniformly 
good results than I had ever obtained before, when 
I used ten to twelve drops of it to the ounce with 
the usual quantities of dilute phosphoric acid and of 
ammonic phosphate—though I have never been able 
to obtain a single successful result when using it with 
pernitrate of iron in the preparation of the yellow 
solution. Unfortunately, however, the weak solution 
of silicic acid, like the common water-glass solution, 
has seemed gradually to deteriorate, and that, too, 
much more rapidly, though in appearance the solution 
shows no change. Up to the present I have never 
been able to repeat successful results with a second 
solution when it was more than four months old. 
Thus, it seems clear that the specimens of water- 
glass with which I first experimented successfully 
must have contained other favouring ingredients not 
present in the ro per cent. solution of sodium silicate ; 
further, that though this solution yielded only barren 
results, yet the colloidal silica prepared from it and 
from strong hydrochloric acid yielded the best results 
of all when used as an ingredient of one of the colour- 
less solutions, but uniformly poor results when. mixed 
with iron for a yellow solution. 
From the point of view of the capability or the 
reverse of the different fluids for engendering living 
2 See ‘‘ The Evolution of Life,” 1907 ; and “‘The Origin of Life,” 2nd 
edition, 1913 (Watts and Co.) 
3 Details on this subject will be found in ‘‘ The Origin of Life,” 2nd edit., 
pp. 86-91. Recently, however, Messrs. Allen and Hanbury have -put me in 
communication with the London agents of their makers of water-glass, who 
have kindly supplied me with some samples of different specific gravity. An 
examination of them leads me to believe that the recent failures have been 
due to my baving been supplied with samples of higher alkalinity than 
formerly. I have made new trials with a sample of 75° sp. gr., after diluting 
it with an equal bulk of distilled water and its behaviour with the other 
reagents (in their usual proportions) seems to be similar to that of the samples 
which I obtained in 1910, so lo g as four or five drops to the ounce are used 
for the ycllow solution, and /hyee drops to the vunce for the colourless 
solution. » Samples of this dituted solution may be obtained from Messrs. 
Allen and Hanbury, of 6 Vere Street, W. 
