Meanings of good preservative in English

But Jack Frost is a good preservative, and so nothing spoiled.

Salt is a good preservative, and apparently natural salt basements have been found in Moscow's netherworld.

Salt is a good preservative, but there is little excuse for our using preserved foods extensively.

A good preservative is to wash or paint them with a very strong solution of fine lime and water.

It is said to dry in about 6 hours and to be a good preservative for fences, barns and other outbuildings.

Paradoxical as it may appear, too much prosperity is often dangerous, and some national misfortune is now and then a good preservative of prosperity.