to keep them safe from frost. They should not be in the sun while
germinating. When the first sprouts appear above the ground let another
set be planted, and so on, till a series is obtained ranging from plants
several inches high to those just starting from the seed. The seeds
themselves should be soaked for a day and the series is then ready
for study. The time required for their growth varies according to the
temperature, moisture, etc. Dr. Goodale says they should be ready in ten
days.[1]

[Footnote 1: Concerning a few Common Plants, by G.L. Goodale, Boston, D.C.
Heath & Co. This little book, which is published, in pamphlet form, for
fifteen cents, will be found exceedingly useful.]

I have never been able to raise them so quickly in the schoolroom, nor
have the pupils to whom I have given them to plant done so at home.
Generally, it is three weeks, at least, before the first specimens are as
large as is desirable.

Germinating seeds need warmth, moisture and air. The necessary conditions
are supplied in the very best way by growing them on sponge, but it would
be difficult to raise enough for a large class in this manner. Place a
piece of moist sponge in a jelly-glass, or any glass that is larger at the
top, so that the sponge may not sink to the bottom, and pour some water
into the glass, but not so much as to touch the sponge. The whole should
be covered with a larger inverted glass, which must not be so close as
to prevent a circulation of air. The plants can thus be watched at every
stage and some should always be grown in this way. The water in the
tumbler will keep the sponge damp, and the roots, after emerging from
the sponge, will grow well in the moist air. Seeds can also be grown on
blotting paper. Put the seeds on several thicknesses of moist blotting