An Essay on the Climate of Ireland. By Joserpn M‘Swerny, M. D. In 
answer to the question proposed by the Royal Irish Academy.—* WHETHER WE 
HAVE REASON TO BELIEVE THAT A CHANGE HAS TAKEN PLACE IN THE CLIMATE OF 
IRELAND, AND IF SUCH CHANGE HAS OCCURRED, THROUGH WHAT PERIOD CAN WE 
TRACE IT, AND TO WHAT CAUSES SHOULD WE ASSIGN IT.” 
Read November 8th, 1830. 
Sepe etiam steriles incendere profuit agros 
Atque levem stipulam crepitantibus urere flammis. 
VireiL. Geor. Lis. 1. 
Dirricutt would be the task of treating of the climate of Ireland at different 
periods, and of drawing conclusions from data so scanty as we possess, but that 
general considerations of the immutable laws of nature aid us in the investigation, 
and we derive no small assistance from the more accurate observations on the climate 
of England, where the history of the weather has been preserved with more care, 
than in Ireland; analogy in this case lends us its powerful aid. 
The comparison of the nature of the vegetation in the island in ancient and modern 
times, and the comparison also of the animal kingdom at different periods, give us 
general views as to the climate. ‘The clothing of the ancient inhabitants, the nature 
_ of their habitations, the casual allusions to the weather made by historians in describ- 
‘ing sieges and battles; all these matters must engage the attention of the person, 
who undertakes to treat of the climate of Ireland at remote periods, when no regular 
accounts of the weather were kept to be handed down to posterity. 
If a stranger were to direct his attention to the subject of the climate of Ireland, 
he would be led to suppose from the situation of the island in a temperate zone, and 
from its situation with respect to the vast Atlantic, to the vapours of which it must be 
exposed, that the climate ought to be mild and moist; but on ascertaining that the 
island contained no mountains of extraordinary height, and on tracing on the map the 
number of rivers by which it is intersected, and amongst them such a river as the 
VOL. XvU. 2u 
