512 
PROFESSOR SIMONDS’S LECTURE. 
were gall stones, the mechanical obstruction thev caused must be 
removed by stimulating the liver to increased action, so as to press 
them onwards into the intestinal canal : when the disease was thus 
occasioned, a good deal of pain, commonly known as colic, resulted. 
These remarks, he said, would lay the foundation for a few 
observations on that affection ordinarily designated the rot in sheep, 
a disease not unknown in this part of the country, but not so 
prevalent as in some other places. No malady was probably so 
much feared by the agriculturists as this, and with reason, for it 
was most destructive to his hopes It was commonly believed to 
be incurable, and therefore it was all-important to inquire into the 
causes which gave rise to it. He need hardly tell them, as practical 
men, that the prevalence of the rot depended very much on the 
quality and kind of food consumed by the animal. Some pastures 
were notorious for rotting sheep; on other lands sheep, under all 
ordinary circumstances, were pastured with impunity: but, as a 
broad principle, it may be laid down that an excess of moisture is 
prejudicial to the health of the animal. Sheep, by nature, are not 
only erratic animals, wandering over a large space of ground, but 
are also inhabitants of arid districts. The skill of man has increased 
and improved the breed, and has naturalised the animal in moist 
and temperate climates. But, nevertheless, circumstances now and 
then take place which shew that its nature is not entirely changed: 
thus, a wet season occurs, the animals are exposed to the debilitating 
effects of moisture, and the rot spreads among them to a fearful ex- 
tent. The malady is not confined to England or to Europe ; it is 
found in Asia and Africa, and occurs also in Egypt on the receding 
of the waters of the Nile. 
These facts are valuable, because they shew that the cause of 
the disease is not local — that it is not produced by climate or 
temperature ; for it was found that animals in any temperature 
became affected, and on any soil in certain seasons. A great deal 
had been written on the rot in sheep, which it were to be wished 
had not been. Many talented individuals had devoted their time 
to its investigation, endeavouring to trace out a cause for it, as if 
it originated from one cause alone. But the facts he had alluded 
to would shew that it arose from more causes than one. He had 
mentioned the circumstance with regard to the land sometimes pro- 
ducing rot and sometimes not; but he would go a step further, and 
ask — was there any particular period of the year when animals 
were more subject to the attack! Undoubtedly there was ! From 
this time to the commencement of the winter is the most likely 
period, and, if a large quantity of rain now fell, the heat and 
moisture combined would produce a most luxuriant herbage; but 
that herbage would be deficient in nutriment, and danger would be 
