DOUBLE, REVERSED ACROSTIC.

A little verb used every day,

Whose letters spell the same each way;

My next, which means to lengthen out,

Spells just the same if turned about;

At close of day you'll find my third,—

Reversed, you have the self-same word;

My fourth, implying "held supreme,"

The same each way, though strange it seem.

An act, these four initials name,

Backward or forward spelled the same.

J.F.B.