M‘Sweeny, on the Climate of Ireland. 229 
is about 55. This does not prove a change of climate ; in the first place the average 
is swelled by the warm year of 1826, and the thermometer is kept in the centre of the 
city, in a situation surrounded by high buildings, where it must be affected by ra- 
diation. Howard has shown, that the mean temperature of London yaries to the 
extent of 44 degrees in different years; therefore Hamilton was not warranted, in 
deducing the mean temperature of Ireland from the observations of a few years. 
Smith’s account of the winds in his day, agrees well enough with the average of 
five years in modern times in Cork. No precise conclusions can be drawn from com- 
parisons between broken fragments of cycles of the weather. 
Kirwan remarks—‘‘ Among all the years observed by Dr. Rutty from 1725 to 
1765, there occurs but one similar to 1792, the year 1755, in that the three seasons, 
spring, summer, and autumn, were wet.”— Transactions ef Royal Irish Academy, 
Vol. V. p. 240. 
It is a generally received opinion, that within the memory of our old peasants, the 
winters have become milder, and the summers less warm ; in this essay it is contended 
for, that the general character of the climate has from a very early period been the 
same; yet it is certain that there is some good reason for this popular opinion, on 
account of a modification of the climate, from the general extension of the potatoe 
culture. 
That the old people should imagine that the summers were warmer formerly, ought 
not to surprise us, as the buoyancy of youth, and warm blood in young days, cause a 
warm glow from moderate exercise; but, on account of the greater liability of old 
people, to be affected by cold, they ought to feel more severely now, winters of the 
same temperature. If no change has taken place, we should expect to hear from them 
complaints of the cold; but on the contrary, the old peasants maintain firmly, that 
the winters formerly were colder. 
Popular and general opinion is not to be slightly passed over. The peasantry of 
France, obtained a signal triumph over the philosophers of their country, with regard 
to the fact of the fall of, meteoric stones. 
The potatoe culture has extended in almost every direction, even up to the tops of 
mountains in some places. The paring and burning of rough ground, makes it 
smooth, and allows the sun to exert its full influence along the surface in winter. On 
rough mountain ground, where there are inequalities, and tufts of heath, and furrows 
worn by the rain, snow in such places is liable to remain a long time undissolved. 
Boate remarked in his time, that there was a greater plenty of snow on the moun- 
tains, than in other parts. 
In summer the shade of the stalks of potatoes protect the ground from the sun, and 
the trenches, which might serve in winter as fit receptacles for keeping snow undis- 
solyed a considerable time, are obliterated by the digging out of the potatoe crop, on 
the approach of severe weather. If the trenches remained during the winter, it is 
