4 
HINTS TO TRAVELLERS, 
anemometers, the approximate velocity in miles per hour corresponding 
to the numbers on the scale has been estimated 
Beaufort’s Scale of Wind Force. 
No. 
Name. 
Velocity in miles 
per hour. 
0 
Calm. 
o to 5 
i 
Light air ... 
5 »* 
2 
Light breeze . 
io „ 15 
3 
Gentle breeze . . > 
15 „ 20 
4 
Moderate breeze . 
20 „ 25 
5 
Fresh breeze . 
25 „ 3 ° 
6 
Strong breeze . 
30 „ 35 
7 
Moderate gale 
35 „ 45 
8 
Fresh gale .... 
45 „ 50 
9 
Strong gale . . . 
50 „ 60 
IO 
Whole gale.... 
60 „ 70 
ii 
Storm. 
70 „ 80 
12 
Hurricane .... 
over 80 
The duration of strong wind should be noted, as well as the time of 
any marked change of strength. The land and sea winds of tropical 
coasts show a well-marked relation to the position of the sun and the 
hour of sunset, and in places where these winds blow the hours of calm 
and change should be noted. On mountain slopes a similar diurnal effect 
may be noticed; the wind usually blows uphill during the day and down¬ 
hill at night, while in valleys it usually blows either with or against 
the direction of the river. Local winds of peculiar character are some¬ 
times met with in association with mountains such as the Fohn of the 
Alps, the Chinook wind of the Rocky Mountains, and the Helm wind of 
the Eden Yalley in England and Adam’s Peak in Ceylon. 
Whirlwinds and tornadoes are rare phenomena, but if met with, it is 
worth while to take some trouble to put on record at least the hour of 
their appearance (local time), the direction in which the whirl moves 
onward, and the breadth of the path of destruction it leaves behind. 
When a storm of wind has passed over a wooded region and blown down 
many trees, the direction in which most of the trunks lie is worth 
observing. The top of the tree usually falls in the direction in which 
