M‘Sweeny, on the Climate of Ireland. 199 
bras, nec ad focos Capricorni rigor invitat, aeris amznitate temperieque tempora fere 
cuncta tepescunt.”— Topog. Hib. dist. 1, cap. 25. 
Again, in another part he observes—‘ Aeris clementia tanta est ut nec nebula in- 
ficiens, nec spiritus hic pestilens nec aura corrumpens, medicorum opera parum indiget 
insula ; morbidos enim homines preter moribundos paucos invenies.”— Topog. Hib. 
Dist. 1, cap. 27. 
The Abbé Ma-Geoghegan, in commenting on this description by Cambrensis, in his 
History of Ireland, remarks thus—‘‘ Cependant le temoignage de Cambrensis me 
paroit un peu suspect, parce qu’ il est outré. En effet les pluies, les neiges et les ge- 
lées y sont assez frequentes en hyver.” He might have shown by the Irish Annals, 
previous to the invasion, and by Ware’s Annals, at a subsequent period, that cold 
winters have been often recorded. It is manifest, by these documents, that the inha- 
bitants of this country were not entirely so free from disease, as Cambrensis described 
them to be. 
In the Irisk Annals, we find that bowel complaints were not unfrequent. In fact, 
distempers of this nature were called by the general name of the country disease. 
Dermot Mac Murrough, the cause of the invasion in the time of Cambrensis, did 
not die of old age, but of disease. The soldiers of the English army were affected 
by sickness. 
It is probable that the armour of the English adventurers, particularly of the chiefs, 
afforded protection, not only against the weapons of the natives, but also protected 
them in some measure, from the drenching rains of the island. 
The expression of Cambrensis is very vague—‘‘ Morbidos enim homines preter 
moribundos paucos invenies.”” It might as well imply that the faculty in those days, 
made quick work with their patients. 
Although the account by Cambrensis, of the climate, is exaggerated, still it may be 
received in evidence, as to the general mildness of the weather in Ireland. 
Kirwan in his work* on the temperature of different latitudes, thinks that ‘‘the as- 
tronomical source of heat is permanent.” If this be the fact on an average of years, 
and if it has held good in former times,t it must follow that less inconvenience was 
felt from heat in summer, at the time of Cambrensis, in Ireland, than at a subsequent 
period, when the woods were cut down. When woods abounded in Ireland, of course 
a great portion of the surface of the island was sheltered from the rays of the sun ; 
therefore, moisture on the ground in the woods, could not be rapidly dried up. 
Evaporation causes a depression of temperature ; the constant evaporation from ex- 
tensive woods must, independently of the shade afforded, have tended to keep the 
surface of the island cool in summer, at the time of Cambrensis. 
* Kirwan, page 107. 
+ There is every reason to think that it has, from the investigation of Professor Schow of Copenhagen. 
