VOL. XIX.] PHILOSOPHICAL TRANSACTIONS. 217 



at length it grew as big as a large white caterpillar ; and from this, according to 

 the usual transformation natural to these smaller animals, came forth this flying 

 insect. 



This plague was happily checked several ways. High winds, wet and misling 

 weather, destroyed many millions of them in a day ; whence we may conclude, 

 that though we have them in these northern moist climates, yet they are more 

 natural, and peculiar to warm and dry countries. Whenever this bad constitu- 

 tion of the air prevailed, their bodies were so enfeebled, that they would let go 

 their hold, and drop to the ground from the branches, and so little a fall as 

 this was sufiicient quite to disable, and sometimes perfectly kill them. Nay, 

 it was observable, that even when they were most vigorous, a slight blow would 

 for some time stun them, if not deprive them of life. During these unfavour- 

 able seasons of weather, the swine and poultry of the country would watch under 

 the trees for their falling, and feed and fatten upon them ; and even the poorer 

 sort of the native Irish, the country then labouring under a scarcity of provi- 

 sion, had a way of dressing them, and lived upon them as food. 



In a little time it was found, that smoke was another thing very offensive to 

 these flies, and by burning heath, fern, and such like weeds, they secured their 

 gardens, and prevented their incursions ; or if they had already entered, by this 

 means they were eftectually driven out again. 



Towards the latter end of the summer, they constantly retired of themselves, 

 and so wholly disappeared, that in a few days you could not see one left. Some 

 thought they took their flight, like swallows and other birds of passage, to a 

 more distant country and warmer climate. But I believe the true reason of 

 their disappearing is, that after their coition is over, for it is about this time 

 they are observed to couple, they retire under ground, in order to lay their 

 spawn there, for a succeeding generation, and likewise to compose themselves 

 to sleep for the rest of the ensuing year, as several other animals are known to 

 do ; for instance, snails among insects, the hedge-hog among the beasts, and 

 as I have good reason to think, the ortygometra or rail among the birds. What 

 further confirms this opinion is, that in the spring time, on digging or plough- 

 ing up the ground, great hollows or nests of them are frequently discovered and 

 broken up, where whole bushels are found together in one heap, but in such a 

 quiet condition, that they seem to have but little life and motion. These large 

 caverns to which they retire, are often met with under a firm solid surface of 

 earth, that has not been stirred or ploughed in many years before, and no mani- 

 fest passage can be discovered by which they could get in. 



A year or two ago, all along the south-west coast of the county of Gallway,, 

 for some miles together, there were found dead on the shore such infinite mul- 

 VOL. IV. Ff 



