hreadlike forms that
gradually rise to the top, it means wind and sudden storm.

[Transcriber's Footnote 1: Dram, drachma; drachm; U.S. Customary System
equal to 1/16 of an ounce or 27.34 grains (1.77 grams). Apothecary weight
equal to 1/8 of an ounce or 60 grains (3.89 grams).]

U. S. DEPARTMENT OF AGRICULTURE WEATHER BUREAU. EXPLANATION OF FLAG
SIGNALS,

[Illustration: Flags]

No. 1, alone, indicates fair weather, stationary temperature.
No. 2, alone. Indicates rain or snow, stationary temperature.
No. 3, alone, indicates local rain, stationary temperature.
No. 1, with No. 4 above it, indicates fair weather, warmer
No. 1, with No. 4 below it, indicates fair weather, colder.
No. 2, with No. 4 above it, indicates warmer weather, rain or snow.
No. 2, with No. 4 below it, indicates colder weather, rain or snow.
No. 8, with No. 4 above it, indicates warmer weather with local rains.
No. 3, with No. 4 below it, indicates colder weather with local rains.
No. 1, with No. 5 above it, indicates fair weather, cold wave.
No. 2, with No. 5 above it, indicates wet weather, cold wave.

Forecasts made at 10 A.M., and displayed between 12 and 1 P.M., forecast
the weather for the following day until 8 P.M.

FORECASTING THE WEATHER 245

Plant Barometers

The dandelion is an excellent barometer, one of the commonest and most
reliable. It is when the blooms have seeded and are in the fluffy,
feathery condition that its weather prophet facilities come to the fore.
In fine weather the ball extends to the full, but when rain approaches, it
shuts like an umbrella. If the weather is inclined to be showery it keeps
shut all the time, only opening when the danger from the wet is past.

The ordinary clover and all its varieties, including the trefoil and the
shamrock, are barometers. When rain is coming, the leaves shut together
like the shells of an oyster and do not open again until fine weather is
assured. For a day or two before rain comes their stems swell to an
appreciable extent and stiffen so that the leaves are borne more upright
than usual. This stem swelling when rain is expected is a feature of many
towering grasses.

The fingers of which the leaves of the horse chestnut are made up keep
flat and fanlike so long as fine weather is likely to continue. With the
coming of rain, however, they droop, as if to offer less resistance to the
weather. The scarlet pimpernel, nicknamed the "poor man's weather glass,"
or wind cope