Purgatory is a scene of affliction and anguish, inasmuch as God's justice gains compensation for the portion of sacrifice and love we have refused Him here below.
Holy angels, guardians of those blazing chasms, help me to call to mind those souls, so holy and resigned, from the bowels of flames that torment them. Make us recognize among them our fathers, our mothers, our sisters and brothers. Let their cries, so tender and heart-rending, capable of splitting the mountains and mollifying cruelty itself, reach and penetrate our ears.
All the above text is by Father Charles Arminjon, from the book The End of the Present World. Father Arminjon goes on to say, "Saint Jerome and several Doctors are of the opinion that, when the Holy Sacrifice is being offered for the intention of a deceased person, he ceases to suffer the pains of Purgatory for the whole duration of the ceremony."
It is still October, not quite the month of the Holy Souls, but knowing what we do about the Holy Souls, imagine what your offering of Holy Communion can do for them. They can only participate in the Eucharistic Sacrifice by our intercession. Our prayers and good works do much to alleviate their suffering, but it is the Holy Sacrifice of the Mass that earns them the most relief. Remember them at every Mass throughout the year.