What is to dissolve gradually and become liquid by attracting and absorbing moisture from the air, as certain salts, acids, and alkalies. In very moist air crystals of strontites deliquesce. Black called?

deliquesce — To dissolve gradually and become liquid by attracting and absorbing moisture from the air, as certain salts, acids, and alkalies. In very moist air crystals of strontites deliquesce. Black. (Webster's 1913.)

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