( 8 )

of tubes 10, 11, and 12 which gave 100 per cent. success in children, and a powerful
reaction in 1-000 dilution on the rabbit. It seems then as if glycerinated lymph were not
unsuitable for Bengal owing to the climate, as in an ordinary way it would not be required
to stand such a severe test as in these experiments. As lymph it is obviously more suitable
than the lanolinated variety, for (1) it contains few or no organisms and inflamed arms
should never occur as they do with lanolinated lymph; (2) it need not be used in such a
hurry. When lanolinated lymph is used too long after its preparation it is overgrown with
extraneous organisms and the virus is weakened. Many failures in vaccination occur from
this cause. The maximum period I can find record of, which has occurred between the issue
of lymph from the Calcutta Depôt and its use is five weeks. The results were unsatisfactory.
Glycerinated lymph would be at about its best five weeks after preparation, and is probably
potent even longer. These experiments, to be complete, should have gone on until the
lymph was found to be losing its potency. I fixed six weeks as the period of the experi-
ments, partly to suit my own convenience, and partly because this is about the maximum
period which might elapse before the use of the lymph, supposing it were issued after a
fortnight's storage when the glycerine has commenced its preservative action and the virus
is potent.

" The tubes I experimented on were not capillary tubes, but ordinary small glass tubes
with corks, such as are in use at present for issuing lanolinated lymph. They proved very
satisfactory.

" With regard to cost I have not worked out the figures exactly, but glycerine is cheaper
than lanolin, and a higher dilution is used. If cold storage were used, the expenses would,
of course, be heavier. I am aware that glycerinated lymph is always stored in the cold,
usually in the ice-box, but the success of these experiments is to me so striking that I am
of opinion that cold storage may be found to be unnecessary. Anyway glycerinated lymph,
with or without cold storage, might be given a trial in Bengal in some selected area, say a
small district, and I shall be surprised if the results are not worth it.

" I have the honour to give below the results of comparison made between glycerinated
and lanolinated lymphs prepared on the same day as to their bacteriological purity after
being for various times at 37° C., and should be obliged if you would add this as a supplement
to my ' Report of experiments as to the effects of heat on glycerinated calf lymph'
forwarded to you under cover of my No. 329S., dated 26th June 1907:—

" The method employed was to weigh out carefully .005 grm. of each of the lymphs to
be tested and spread on a sterile agar plate (freshly poured) with a sterile glass bent rod.

" It will be seen that the results all point to the action of glycerine in causing the colonies
to die out whilst in lanoline they increase."

Different methods of vaccina-
tion.

13. During the past year, excluding 44,820 vaccination operations
performed in the Tributary States of Patna and
Sonepur in Orissa, which could not be classified
for want of necessary information, 93,049 primary
vaccinations were performed with lymph taken direct from the calf, 775,319
with lanoline lymph, and 979,753 by the arm-to-arm method, against 87,803,
696,415 and 1,090,758 respectively during the preceding year and 151,080,
400,847, and 1,352,698 of the year before (1905-06.) The ratio per cent. of