The Rot in Sheep. 
81 
it ni.iy appear. I shall hero content myself, however," he says, 
"with statinf^ a fact recorded by the learned and inj^enious ])r. 
George Pearson, in a letter to Arthur Young, Escj., which power- 
fully militates against the hypothesis in cjuestion," and he adds, 
"as this comnumication is valuable, not only for the fact it 
contains, but on account of the philosophical spirit which per- 
vades it, I deem no apology necessary for presenting it to my 
readers in Dr, Pearson's own words : — 
" The jiapcr lately written by my friend Dr. Harrison on the rot of sliecp 
is very valuable indeed for the great number of facts with which it is enriched. 
These lacts are of various ajiplications for the economist, the agriculturist, the 
breeder, and the practitioner of physic. The subject of the rot in general, I 
am persuaded, is in very able hands for further investigation, as Dr. Harrison's 
opportunities, from his residence, are most favourable. Hence, if I had leisure,, 
I should not be inclined to occupy myself in this inquiry ; but it may, perliaps; 
be the means of eliciting or of confirming truth to state an apparent objcctioii- 
to the ingenious author's conclusion — ' that the rot is occasioned hy the same 
morhific agent ivhich occasions intermiitcid and remittent fevers' This mor-- 
bitic matter is called 7iiiasmata puludum in the schools of physic, and those 
}niasmata arc engendered especially in marshy and boggy grounds or fens, 
]iarticularly in the spring and autumnal season. In some of the marshes of 
Kent intermittent fevers affect a great proportion of the inhabitants ; and eveU' 
persons in the neighbourhood, although living on dry chalky lands, where 
these disorders never appear if remote from the low grounds, unless by im- 
portation. I was lately in Chitney Marsh, on the iledway, near the Isle of 
Shejipey, one of the most prolific situations for agues to be found in the king- 
dom. It is famous also for its pasturage, by which very gi-eat numbers of 
sheep are fed. Observing the sallow, and indeed cadaverous, countenances of 
the inhabitants, most of whom were ill or were recovering from agues, I was 
led" to inquire into the health of the sheep. Besides the evidence of the fine 
healthy condition of these animals I obtained that of the shepherd, who had' 
been so. fortunate as to live thirty-six years in the marsh. He attested thathc' 
had only seen the disorder once, and that was in the first year of his residence,, 
nor is the rot at all common in any part of Kent. The Leicestershire breed,, 
he said, were subject to it, but not the sheep bred in the marsh ; nor were 
these animals subject to any other disease more frequently than in other situ- 
ations in general, or particnlarh^ in the uplands. Hence it appears that one 
kind of miasmata of marshes which produce agues do not in all situations also 
produce rot. It is not, however, logically just to conclude from the instance I 
have given that miasmata paludum of a different species may not occasion the 
rot and also agues. It is possible, also, that some concomitant agents or cir- 
cumstances may render the same miasmata productive of one of the diseases in 
certain situations, but not of the other disease." 
Harrison also, like Mr. Youatt, narrates some cases of exemp- 
tion from rot which militate very much against his theory. He 
says that " in 1792, the fatal year, &c., often particularised, Mr. 
loung of Claxby divided a flock of sheep and placed fifty upon 
some good aftermath, where, in other seasons, the rot had fre- 
quently prevailed. Only this part of his flock escaped the dis- 
order, which he attributed to the rneadow not having been grazed, 
before it was well covered and defended from the weather." 
VOL. xxiir. G 
