5
is that there is an enteric or other history in connection with the patient, and. it i8
for the clinician to determine whether the present or a past condition is responsible
for the reaction. Vice versa When the reaction reported is a negative one, that is
not tantamount to saying that the patient has not got typhoid or other fever.
There is also some difference of opinion as to what constitutes a positive
reaction. Bearing in mind the above-mentioned limitations as to what is meant by
a, positive reaction, I consider that it is better to report an action positive if there
is a reasonable amount of agglutination in a dilution of one in thirty in half an
hour. A positive report can only lead to greater vigilance, while a negative one
might mislead the ,medical attendant to the detriment of the patient. If, however,
as maintained by some authorities, you can only regard a reaction as positive when
it is complete at a dilution of one in thirty in fifteen minutes, and marked at one in
a hundred in half an hour, you must exclude all those incipient reactions which are
sometimes the first guiding clue that a physician has in a puzzling case. Further
it is just in the ill-defined cases that most help is required. Since the 15th of Sep-
tember in addition to the report at dilution one in thirty-two, the reaction at one
in a hundred after one hour has been given. Two hundred and ninety-two tests
were made and of these 142 gave a positive reaction to enteric germs. Thirty-three
of these were tested up to a dilution of one in a hundred and 25 reacted positively
at that dilution. Out of 16 tests for Paratyphoid. B., 8 were positive, and out of
these 8, 6 also reacted to enteric germs. Fifteen tests against B. Gartner euteritidis
gave only one positive reaction, while of 7 tests against Paratyphoid A., and 6
against Micrococcus melitensis , all were negative.
(4) Malaria.—As in past years there were a great many failures to detect
parasites in the specimens submitted for examination. Out of 74 specimens 59
gave negative results, but 17 or more than a quarter of these showed the definite
increase of the large mononuclear cells so characteristic of malaria. The failure
to find parasites in these cases is probably due to the practice of giving quinine
before a specimen of the blood is taken. As stated in last year's report this should
never be done. It may not be possible to have the specimen examined before
.quinine is administered, but if the case is being attended by a medical man the
!.specimen can always be taken.
(5) Leucocytic Counts.--Among five specimens submitted for a differential
count of the leucocytes none showed a marked variation from the normal.
1
(6) Sputum for Tubercle bacilli.—Out of 37 specimens, 11 showed the presence
of these organisms.
None of the other headings call for remark except the last. There were far
fewer unsuitable specimens submitted this year. Most of these she-wed no trace of
having been derived from the source stated.
Water Analysis.—Three hundred and ninety-two complete bacteriological, and
-260 complete chemical examinations of water were carried out. Eighty four and
77, respectively, of these were conducted on samples derived from various sources ;
-the remainder were upon samples from municipal and jail supplies in, the Presidency,
-the results of which are given in appendices I and II.
1
Laboratory Note—Romanowsky stain.—The Senior Laboratory Assistant
M.R.Ry. T. Seethapathy Aiyar, L.M. &. s., has called my attention to a point in the
reparation of this very useful stain, the results obtained with which have been
however very variable in different hands. In giving directions for making up the
stain, none of the text books specify whether the carbonate of soda used should be
;'
Anhydrous or crystalline. As crystalline carbonate of soda contains 63 per cent. of
water, the question is not a negli g ible one. In this laboratory we have got consis-
-gently good results by using 0 . 35r'per cent. of anhydrous carbonate of soda. The
r usitally quoted 0 . 5 per cent. is definitely too much if anhydrous soda be used.
, An accidental adaptation by Assistant Surgeon T. Seethapathy Aiyar of the
method of washing out the hæmoglobin while searching for parasites in scanty
- infections, devised. by Ronald Ross, is perhaps worthy of mention. While staining
a s l i d e c o n t a i n i n g
inin trypanosomes by the Romanowsky method, the preliminary
0
*
fixation was accidentally omitted. As a result all the red corpuscles were rendered
visible and the well-stained trypanosomes stood out with beautiful clearness.
2