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13
APPENDIX.
Dr. Klein's Reports.
July 23rd, 1898.
I beg herewith to report on the bacterioscopic analysis of three samples* of " ice-cream " delivered
here by Dr. Hamer, on July 10th, 1898. The examination of^these samples was directed—
(a) To ascertaining the number of microbes.
(b) To ascertaining, by special method of cultivation, the number of bacillus coli, and of
proteus vulgaris.
(c) To ascertaining the number of bacillus enteritidis sporogenes, and
(d) To ascertaining the number of any other pathogenic microbes.
(a) As to numbers.
All three samples contained such an abundance of liquefying microbes, that all agar plates made
with l-100th part of a cubic centimetre were crowded with innumerable colonies. The gelatine plates
made with the same amount were completely liquefied in 48 hours. On a rough estimate—the only one
possible under the circumstances—there must have been present at least a million microbes per 1 c.c.
of the materials.
(b) From none of the samples was the typical bacillus coli isolated.
Proteus vulgaris was present in sample number 2, to an enormous extent, in fact aerobic
cultures made from this sample seemed a pure culture of proteus vulgaris. Sample number 3 contained
a small number of proteus vulgaris, of course nothing like sample number 2. Sample number 1 was
free from proteus vulgaris.
(c) None of the samples 1, 2, 3, contained the spores of the bacillus enteritidis.
(d) Only sample number 2 contained spores of the anaerobic bacillus butyricus.
No pathogenic microbe was found in any of the samples.
Sample number 1 contained the harmless sporing bacillus mesentericus in almost pure culture,
sample number 2 was free from this, sample number 3 contained a fair number of these microbes.
This is one of the microbes which in milk produces curdling and acidity, and in accordance with
the above observations, both samples number 1 and 3 on being kept for 48 hours, at the temperature
of the room—the bottles being closed—developed a marked smell of souring, and on testing with
litmus, the materials were strongly acid.
Sample number 2, on the other hand, as might be expected from its containing enormous
numbers of proteus vulgaris, was completely decomposed in 48 hours, with foul smell and emanation
of nauseous gases.
It follows from this that samples numbers 1 and 3 were practically harmless, number 1 more
so than number 3, but sample number 2 had all the elements of, and had actually commenced to
undergo putrid decomposition, and for this reason I should not consider this sample free from danger.
October 4th, 1898,
I beg herewith to report on the bacterioscopic examination of the three samples! of ice-cream
delivered here by Dr. Hamer on September 29th. These three samples were labelled respectively,
A, B and C. All these samples have the appearance of thick custard.
The examination in ail these cases was made—
(a) For ascertaining approximately the number of microbes present in the material.
(b) For ascertaining the number of bacillus coli and of proteus.
(c) For ascertaining the number of liquefying anaerobes, and
(d) For ascertaining the number of spores of bacillus enteritidis sporogenes.
The result of these examinations was as follows—
(a) Sample A contained in five cubic millimetres (one 1-200 part of a cubic centimetre)
so great a number of microbes that the colonies developing in a plate made with five cubic
millimetres could not be easily counted on account of their excessive numbers (over two millions per
cubic centimetre.)
Sample B contained 126 colonies per five cubic millimetres, that is to say 25,200 in 1 c.c.
Sample C contained microbes as numerously as A., i.e., over two millions per 1 c.c.
Amongst the microbes present in A and C, there were about 150 colonies of bacillus coli, and a
very great number of bacterium lactis per five cubic millimetre plate; this shows that in these samples
a very abundant multiplication of these two microbes must have taken place previous to the delivery
of the samples, milk, and milk preparations being an excellent soil for the rapid multiplication of these
microbes.
In sample B the microbes obtained in a plate made with 5 cubic millimetres were most of them
of the nature of bacterium lactis and of liquefying cocci.
(b) Sample A and sample C contained, as already stated, a large number of typical bacillus
coli (over 150 per 5 cubic millimetres), and it has also been stated that their number is easily accounted
for by their rapid multiplication in milk and milk preparations even at the ordinary temperature.
In addition to bacillus coli both samples A and C contained very numerously proteus Zenkeri, and
sample C in addition contained three colonies of proteus vulgaris per 10 cubic millimetres (1-100th
of c.c.) Sample B contained one colony of bacillus coli per 10 cubic millimetres, no proteus Zenkeri
and no proteus vulgaris.
(c) None of the samples contained liquefying sporing anaerobes.
(d) None of the samples contained the spores of bacillus enteritidis sporogenes.
From these examinations it follows that sample B was bacteriologically the cleanest. Samples
A and C were materials of an impure character. Particularly sample C was inferior to sample A
since it contained proteus vulgaris in addition to bacillus coli and proteus Zenkeri. None of the
samples contained any pathogenic microbe, at any rate none contained the bacillus enteritidis.
*These samples were taken from Italian ice-cream vendors,
†These samples were taken from a club, an hotel, and a well-known restaurant.