Ronald Ross Nobel Lecture

64

    1 9 0 2   R.R OS S

The cold weather came on apace, and at first it appeared to be utterly im-

possible to work. There were no cases of malaria and scarcely any mosquitoes.

Much to my pleasure, however, I found a few dappled-winged gnats, and

observed again that their larvae lived in water on the ground - namely in a pit

and an old well - apparently almost as dormant as the adults were. I kept a

single one alive in a bottle for two months without its developing.

Shortly after arrival at Kherwara I wrote down a brief account of the find-

ing of the pigmented cells in the third and fourth mosquitoes. At the end of

January the British Medical J

 

ournal containing my previous paper on the

cells

38

, together with remarks by Manson, Bland Sutton, and Thin, reached

me. I therefore rewrote the beginning of my second paper; and added a refer-

ence to some work which I had been able to do with pigeons, and also a long

discussion of Thin’s remarks, in which I showed that his position with regard

to the pigmented cells was untenable. The paper was published in February.

I did not explicitly say that the third dappled-winged mosquito had been bred

from the larva in captivity, because it was evident that this fact would be in-

ferred from the opening of the first paper of which the second was obviously

a continuation. But I said that the grey mosquito in which pigmented cells

had been found was "observed feeding on a patient", and that "I judged for

many reasons that it had been feeding occasionally on the same man for several

days" showing clearly enough that this insect had not been bred from the

larva in captivity. The facts might have been put more explicitly at the time;

but they are apparent enough to any candid reader.* In the paper the order of

the third and fourth mosquitoes is changed for purposes of description - the

case of the grey mosquito being put last because it was doubtful.

The work with pigeons just referred to was as follows. Being unable to ob-

tain cases of human malaria I turned to the malaria of birds which had long

been known to harbour parasites closely similar in appearance and life-history

to the malaria parasites of man. Both Manson and I had long recognized the

technical advantages of working with these organisms. I immediately found

the parasites of Labbé’s genus Halteridium in the pigeons of Kherwara; but

could not induce mosquitoes to bite the birds. Observing, however, that they

were infested by a species of blood-sucking fly, I examined thirty of these, and

* When I

 

wrote these papers I did not suspect that every line of mine, even in some of

my private letters, would be subjected to a minute and unscrupulous analysis in the hope

of finding discrepancies which would serve to discredit my observations. Every possible

artifice has been used for this purpose by the very men who learnt all they knew from

these very publications.

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    R E S E A R C H E S   O N   M A L A R I A

65

some lice, fed on infected pigeons. No pigmented cells were, however, found

in them.

At last when the weather became warmer in February several cases of quar-

tan fever occurred among the troops, probably relapses. The dappled-winged

mosquitoes still refused to bite; but I succeeded in feeding a number of brin-

dled mosquitoes of a peculiar brown species on the cases. The results were again

negative in thirty-four of these insects.

I was just about to apply for my pension when welcome news arrived. I had

of course given full details of my sudden transfer to Manson; and he had ex-

erted himself to influence the government of India and the Director General

of the Indian Medical Service (then Surgeon General Cleghorn) to put me on

special duty to continue my researches. I had urged the same thing upon the

Director General; but, unfortunately as it happened, suggested that one good

place for the work would be Assam, where an epidemic of kala-azar - a disease

which Rogers had recently reported to be malaria - had long been raging.

However, I now received a telegram stating that I had been placed on special

duty to investigate malaria and kala-azar in Calcutta and Assam for six

months.* My five months’ imprisonment was at an end. I arrived in Calcutta

on the 17th February 1898; and was joined there by my family, with all my

books and notes which had been with them at Bangalore all this time.

15. Calcutta (February-April, 1898). The theory proved. 

Now in recompense

for the tribulations of Kherwara, opened a glorious time, during which the

amazing story of malaria was unrolled little by little. The great induction had

given the clue; now, following the clue step by step, we were to be led into

regions where Nature revealed herself wonderful beyond the imagination of

any of us. In the background was something greater still - the possibility of

saving human life on the large scale.

I am happy to be able to begin this part of the narrative with a brief account

of the brilliant and important discovery of MacCallum. It will be remembered

that Manson had thought the motile filaments to be flagellated spores; that I

had studied them much without being able to learn anything new about them

except that they are certainly living organisms; and that when I finally found

the pigmented cells I thought that these were derived from the motile fila-

ments, and had absorbed their melanin from the haemoglobin in the stomach

cavity of the insects. In his letter of the 11th August however, Manson sent

me a paper by Simond, suggesting that the similar motile filaments of certain

* Afterwards extended to one year.

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