grief increases by concealing

Scene [I]: The Cave
     [enter Sorceress]
     
     [PRELUDE FOR THE WITCHES]
     
     SORCERESS
     Wayward sisters, you that fright
     The lonely traveller by night
     Who, like dismal ravens crying,
     Beat the windows of the dying,
     Appear! Appear at my call, and share in the fame
     Of a mischief shall make all Carthage flame.
     Appear!
     [enter Enchantresses]

 ACT THE FIRST
     
     Scene: The Palace
     [enter Dido, Belinda and train]
     
     BELINDA
     Shake the cloud from off your brow,
     Fate your wishes does allow;
        Empire growing,
        Pleasures flowing,
     Fortune smiles and so should you.
     
     CHORUS
     Banish sorrow, banish care,
     Grief should ne'er approach the fair.
     
     DIDO
     Ah! Belinda, I am prest
     With torment not to be Confest,
     Peace and I are strangers grown.
     I languish till my grief is known,
     Yet would not have it guest.
     
     BELINDA
     Grief increases by concealing,

 DIDO
     Mine admits of no revealing.