( 67 ) 
The scheme is pasted on card-board and for each counting covered 
with tracing-paper, whereon of each field the number of the counted 
organisms is recorded; in this way the same scheme-table can be used 
every time again (provided the cover-glasses be of the same size). 
The preparation is set in on the centre of the cover-glass; the 
position of the two verniers of the object-stage is marked on the 
tracing-paper, so that this point can always be found back; around 
it the several fields are grouped. 
When human faeces are treated in this way, there mostly appears 
to exist a great disproportion between the number of bacteria which 
can be counted microscopically, and that which can be grown on 
some fitted medium; this disproportion is so great that it is obvious 
even in the ordinary staining-method after Koc, although numerous 
organisms are then washed away. Accordingly, some investigators as 
Bucnyer, Kuisu, EBERLE, and others, drew attention to this fact. As 
however, no exact method was known to microscopically determine 
the number of bacteria, and thus, partly no quantitative estimations 
were made, partly imperfect methods could only be worked with 
the importance of the fact was not acknowledged, still less tried 
to explain it. 
When applying the microscopic counting-method and the culture- 
method to alkalin gelatin at 22° C., the differences often prove 
exceedingly great; to give a few instances: in | mgr. of faeces, 
were counted microscopically 74.959000 bacteria, found by the 
culture-method 356; 2nd instance: microscopic counting 165.614000, 
cultivated 9900; ete. 
At first view it might be presumed that the greater part of the 
enormous number of organisms, which are seen microscopically, 
are in the same condition as the few cultivable bacteria, 1. e. also 
living and fitted for development, but that the difference might 
be quite, or at least greatly explained by the distribution in 
clumps of the faeces-bacteria each clump producing but one single 
colony, whilst in the counting-method each organism is reckoned 
separately. It is in fact very troublesome to make a good emul- 
sion of faeces, wherein the bacteria are equally distributed, but 
if following the above method, it nearly always succeeds, which 
may directly be controlled from the microscopic preparation. Also 
the excessively great differences which are found, likewise a priori 
contradict this view. In order, however, completely to exclude 
this possibility, a series of determinations was made, where in the 
microscopic preparation not only each organism was counted, but 
moreover in each counted field the number (reduced number) was 
5* 
