2. Any heavy matter put into the car of a balloon to give it
steadiness.
3. Gravel, broken stone, etc., laid in the bed of a railroad
to make it firm and solid.
4. The larger solids, as broken stone or gravel, used in
making concrete.
5. Fig.: That which gives, or helps to maintain, uprightness,
steadiness, and security.
It [piety] is the right ballast of prosperity.
--Barrow.
{Ballast engine}, a steam engine used in excavating and for
digging and raising stones and gravel for ballast.
{Ship in ballast}, a ship carring only ballast.
2. To fill in, as the bed of a railroad, with gravel, stone,
etc., in order to make it firm and solid.
3. To keep steady; to steady, morally.
'T is charity must ballast the heart. --Hammond.