52 Major Lachlan on the Rise and Fall of the Lakes. 
versa. The Seiches have always been considerable when the 
atmosphere has been loaded with heavy clouds, or when the 
weather, in other respects severe, has threatened to be stormy, 
and when the barometer has sunk. Ath. That though Seiches 
are more frequent in spring and autumn, they are.more consider- 
ble in the summer, and, in particular, "towards the close of the 
season. The highest that have been observed happened in the 
month of September. 5th. That the minimum of the Seiches 
has no precise term: their maximum seems to be five feet. 6th. 
That although the duration of the: Seiches is very variable, the 
greatest extent seems not to exceed 20 or 25 minutes, but usu- 
ally lasts a much shorter time. And 7th, That they are not pe- 
culiar to the Lake of Geneva alone; M. Vaucher having observed 
them on the Lakes of Zurich, of Annecy, and of Constance.” 
I cannot refrain from also quoting the following paragraph from 
the same , as much to the point :— 
“Tt appears Sicocstionsble that the phenomenon of the Seiches 
is due to an unequal pressure of the atmosphere in different parts 
of the Lake at the time, 7. e., to the simultaneous effects of 
columns of air of different. weight, or different elasticity, arising 
from cone: age of temp perare, or from mechanic cal 
and even eee oa must be wahieot to the same in 
and fp 
therefore present the same phenomenon ; and I Novotna, doubt A 
that correct observations will verify the presumption”* = 
ith respect to the irregular tides observable in the Baltic and 
Black Seas, and other great bodies of saline water of a similar 
character, it will be sufficient to give the following, —_ the | 
first-named sea, from a standard geographical work, as bearin 
intimately on the subject under discussion :— The Baltic being 
autumn or winter, at the time of heavy ra ins, or when the at 
mosphere is charged with clouds, though unattended with falling 
weather. The water maintains its height frequently for several 
days, sometimes even for weeks. Prevalent winds, flooding rains, 
melting snows, and many other causes were assigned for this 
very remarkable phenomenon ; but it continued to occur, inde- 
pendent of all these, till 1804, when Schulten, a Swedish physi- 
cian, after having collected all the observations that had _ 
made, found ‘that the greatest height of the water corresponds 
with the greatest depression of the barometrical column ; and 
conversely.’ The almost total absence of oceanic action in this 
* See Canadian Journal, vol. ii, pp. 27, 28, &c. 
