from St. Ignatius' Eleventh Rule. The eleventh: let one who is consoled seek to humble himself and lower himself as much as he can, thinking of how little he is capable in the time of desolation without such grace or consolation. On the contrary, let one who is in desolation think that he can do much with God's sufficient grace to resist all his enemies, taking strength in his Creator and Lord.
About Desolation:that state of interior disturbance, 'darkness of soul; turmoil of spirit; urgings to what is low and earthly; restlessness rising from many disturbances and temptations, which lead to want of faith, want of hope, want of love.
About consolation:that state of interior warmth 'by which the soul is inflamed with the love of its Creator and Lord'. This includes 'tears that move to the love of God, whether it be because of sorrow for sins, or because of the sufferings of Christ our Lord, or for any other reason that is immediately directed to the praise and service of God'.
from http://www.holyspiritinteractive.net/columns/fiomascarenhas/scripturallyspeaking/19.asp and St. Ignatius