SEICHES AND OTHER OSCILLATIONS 53 
Some Foreign Lakes 
Lake. 
reriod i^. 
Length in 
Miles. 
Depth i 
Max. 
n Feet. 
Mean. 
Erie 
960-840 
250 
180 
George . 
131 
18 
16 
Geneva .... . . 
73 
45 
1014 
500 
Constance ..... 
56 
41 
827 
295 
Neucliatel ..... 
50 
24 
502 
210 
Ziiricli ...... 
• 46 
18 
470 
144 
Lucerne ...... 
45 
24 
732 
Walen ...... 
15 
10 
496 
Traun ...... 
10 
7 
627 
Brienz ...... 
10 
9 
856 
Scottish Lakes' 
Lake. 
Periods. 
Ti 
Length 
Depth 
in Feet. 
in Miles. 
T2 
Max. 
Mean. 
Ness ..... 
31-5 
15-3 
2-06 
24 
754 
433 
Tay 
28-4 
16-4 
1-73 
15 
508 
199 
Laggan .... 
26-6 
7 
174 
68 
Lubnaig .... 
24-4 
4 
146 
43 
Arkaig .... 
24 
12 
359 
153 
Maree . ' . 
15 
13 
367 
125 
Earn 
14-5 
8-1 
1-79 
6 
287 
138 
Morar .... 
14 
12 
1017 
284 
Fada 
11-5 
6' 
l'-91 
4 
248 
102 
Chroisg .... 
11-2 
3 
168 
74 
Treig 
9-2 
5-2 
1-77 
5 
436 
207 
Periods and Nodes of Loch Earn 
In order to calculate the periods and nodes of Loch Earn, twenty- 
nine points on its normal curve were determined from the bathymetrical 
data of the Scottish Lake Survey. A pair of parabolae with a 
common vertex and vertical axis were then determined to fit these 
points as nearly as possible. This was to some extent an arbitrary 
process, and to avoid possible bias a particular application of the 
method of least squares was used to determine the parabolic constants. 
The nature of the fit will be seen from fig. 19. There is good general 
agreement between the punctuated normal curve and the biparabolic 
curve, but also considerable deviations in certain places. It was 
^ Except for Lochs Treig, Ness, Earn, and Tay, the determinations are very 
rough. 
