History of Aiiiinal Plagitcs. 261 



sician at Dumfries, in an Essay on ^ Nervous Fevers/ notices 

 it casually as follows : ^ One thing I would not miss to take 

 notice of here : the distemper so mortal amongst the cattle 

 in this country, is a fever of a particular kind. I know of 

 no medicine that has been of much service, either to pre- 

 vent or to cure it. The most successful method to prevent 

 it is, when the cattle are thought to be infected, or the in- 

 fection near, to change the grass, by which they are purged, 

 and this is the ordinary effect of new grass. We cannot think 

 that it is owing to the particular qualities of the grass as a 

 proper antidote that they are preserved, grass being much the 

 same everywhere; but it must be from its purging quality, for 

 if this visible effect does not follow, I'm afraid they will not 

 escape. This suggests to us the use of purgatives in this disease 

 of the cattle, which, amongst the many remedies handed about, 

 and said to do wonders, is scarce ever thou2:ht of.' ' Havinsr 

 mentioned this disease of the cattle, a comparison might be made 

 betwixt it and some fevers that have affected human bodies, so 

 far as they may be found to proceed from the same first cause, 

 viz. the air and weather. For some years the seasons have not 

 been orderly. They have been unkindly, as they say. Warm 

 open winters without frost, rainy summers and harvests, have 

 been generally complained of. If by these a distemperature of 

 the fluids is brought on, it will be kept up so long as the general 

 course of the weather is the same.' ^ 



A.D. 1736-7. The weather was intensely hot during the 

 summer of 1736 in England, and gnats were so numerous all 

 over the country, but more especially in the neighbourhood of 

 Salisbury and Wiltshire, that they occasioned great annoy- 

 ance. Flying in dense clouds, they sometimes were observed 

 to ascend above Salisbury Cathedral spire. In 1737 there was 

 an eruption of Mount Vesuvius and a comet, as well as some 

 shocks of earthquake. Influenza in man in England in ^^fi. 'A 

 pestilential distemper made sad havoc of the cattle and swine in 

 the south of Devonshire in October.' ' In January, '37, catarrh- 



' Dr Gilchrist. Medical Essays and Observations by a Society in Edinburgh. 

 Edinburgh, 1737, vol. iv. p. 366. 

 2 T. Short. Op. cit., p. iii. 



