elevation of five miles, or more, when too delicate
to be visible below.

+------------------------------------------------+
| | 3 miles.
|Cirrus. |
| Cirro-cumulus. |
| Cirro-stratus. |
| |
Primary | { Cumulus extending up |
stratum. | { in violent showers. |
| |
| |
|Stratus. |
|------------------------------------------------|
| | 1-1/2 miles.
Scud & |N. W. scud. { Cumulus Storm scud. |
cumulus |Fair-weather { ordinarily and |
stratum. | { its base always. |
| |
|------------------------------------------------|
| | 1/2 mile.
Fog |High fog. Storm fog. |
stratum. | |
| Low fog at the surface of the earth. |
| |
+------------------------------------------------+

With the assistance of this table of elevations, and a careful
observation, the reader can soon become familiar with the forms of clouds
and their relative situations.

CHAPTER III.

Having thus taken a brief view of the different clouds, let us return to
the inquiry, from what ocean, and by what machinery, _our_ "rivers
return."

Not wholly or mainly from the North Atlantic, although it lies adjacent to
us, and they often _seem_ to do so; for, first, all storms, showers, and
clouds, which furnish, _independently_, any appreciable quantity of rain
to the United States, and even adjacent to the Atlantic, or indeed to the
Atlantic itself, come from a westerly point, and pass to the eastward.
_This is a general, uniform, and invariable law, although there is in
different places, and in the same place at different times, some variation
in thei