On Malaria. 
67 
of waters next to be noticed, it is popularly said that they cannot be pernicious, be- 
cause the water is constantly refreshed by a stream, it is a false as well as a dan- 
gerous opinion. Should such a receptacle admit a stream that replaced the whole 
water in a few hours, which is rarely the case, it would even then be no other 
than a slow river, and therefore no more free of danger than the worst of those. 
In proportion as any species of soil or place is least suspected and most common, 
it seems the more necessary to be careful in pointing it out and dwelling on it ; 
and hence it is, that 1 am more desirous of urging the dangers arising from what 
will, I know, be despised, as I have experienced it to be. I allude here to a j-reat 
variety of apparently insignificant waters, comprising mill-ponds for various pur- 
poses and on all scales ; ornamental waters and fish-ponds, canals, and the endless 
pools and ponds found all ocer the country, in deserted gravel pits, and in various 
other casual situations not worth detailing 
It is always useful to examine any case of this nature by reducing it to its princi- 
ples, or by a philosophical analysis, and to inquire whether it ought not to he in- 
salubrious, before inquiring whether it actually is so. Now all these waters, be 
they what they may, include the elements of a marsh or of a water productive of 
malaiia. Their margins are marshes, they contain aquatic and putrefying plants ; 
and under the heat of summer, they disclose mud impregnated with vegetable 
matter. And this is true of the whole, whatever their extent or character maybe ; 
while, if plainly shown that bulk or space is not necessary even to a marsh, and 
that our climate is adequate to the production of malaria, there is no reason, d 
priori, why they should not produce it. 
Now let us see how the experience confirms this; and if it does, then are we 
in possessioJi of a very extensive class of causes of disease, and of one which very 
especially we have in our power as to correction, which, and not the excitement of 
useless alarm, is the object of this paper. 
Volney*s testimony as to the pernicious nature of mill-ponds, is decided as to 
America; and I have just quoted it. Won falcon is equally decided as to the poi- 
sonous qualities of all such waters in France; and all the Italian writers agree 
that it is the same in their own country. And the evil does not depend on the 
name by which they arc known* or upon their physiognomy or uses, any more 
than it does on their dimensions mo mark a few of specific kinds which are con- 
demned in foreign countries, as a guide to our judgments respecting our own. 
There are many extensive districts in France occupied by ponds rather than 
lakes, maintained and farmed for an inland fishery, where the diseases from ma- 
laria prevail to such an extent, that the average of life does not exceed twenty years; 
where the people are decimated in every year ; where absolute old age, in those who 
survive so long, takes place at forty ; ami where the aspect of twenty is that of 
fifty or sixty in countries such as our own ; where even the children are diseased 
from their births, becoming subject to unceasing fevers if they live to seven, and 
thus continuing till the not far distant period of death arrives to terminate the 
literally long disease of life. I can here refer to Monfalcon for details that I 
dare not enlarge on, and for authority that no one will question. 
Here is proof of the ellec:. of such waters : and 1 will use the same writer's 
authority as to condemnation of all canals, ponds, and ornamental waters, of what- 
ever nature ; besides which, as to those who desire facts more specific, his word 
and that of other French physicians, will probably be taken for the fact, that the 
41 canal” at Versailles, and the similar water at the Chantilly, which are mere 
ponds scarcely exceeding that in St. James’s Square, are the common causes of 
severe intermittent and remittent fevers. 
I need not quote further foreign authorities. They who doubt, may not, perhaps, 
take my word for the fact ; but while I could point out, in this country of ours, 
the same occurrences in abundance everywhere, from many waters of this nature, 
1 shall prefer trusting to the examination of others hereafter : since a conviction 
derived from such a source will be of much more value than a belief founded on 
any evidence which I could produce ; marked as that is, and easy as it would be, to 
point out the very places, often familiar to the inhabitants even of this capital. 
But that I may make these remarks of the more utility, let me note one or two 
other particulars ; since, as far as reformation or avoidance of the cause is attaina- 
ble, the value of these remarks must depend on their specific nature. 
If any one will be at the trouble of examining the condition of health and the 
characters of the disorders, and further, the time of the year, and the particular 
kind of seasons in which these prevail, as these relate to the inhabitants of such 
