See this online ebook:

  • Calvary and the Altar; or, Devotions for the Octave of the Blessed Sacrament, the Forty Hours (Quarant’ ore) and the Days of Perpetual Adoration, by Mademoiselle [Léonie] Guillemaut; translated and with a preface by Lady Herbert [Mary Elizabeth Herbert, Baroness] (London, Dublin, Derby: Thomas Richardson and Son; New York: Henry H. Richardson & Co., 1870). Available in pdf, mobi/kindle, epub, and other formats at Internet Archive.

See also these texts and ebooks on the Sacrament of the Eucharist:

On the Most Holy Sacrifice of the Mass, see the following books and texts:

On the worthy reception of Christ our Lord in Holy Communion, see the books and texts listed in our post “Online texts: Commentaries on ‘Amoris Laetitia’“, as well as the following texts:

Posted on the Feast of Corpus Christi in the Roman Rite. For other online texts and legally free ebooks, you may access the List of Free eBooks (Arranged by Title) and the List of Free eBooks (Grouped by Subject).

“For I have received of the Lord that which also I delivered to you, that the Lord Jesus, the night in which he was betrayed, took bread, And giving thanks, broke, and said: Take ye, and eat: this is my body, which shall be delivered for you: do this for the commemoration of me. In like manner also the chalice, after he had supped, saying: This chalice is the new testament in my blood: this do ye, as often as you shall drink it for the commemoration of me.

“For as often as you shall eat this bread, and drink the chalice, you shall shew the death of the Lord until he come. Wherefore, whosoever shall eat this bread, or drink the chalice of the Lord unworthily, shall be guilty of the body and of the blood of the Lord. But let a man prove himself: and so let him eat of that bread, and drink of the chalice. For he that eateth and drinketh unworthily, eateth and drinketh judgment to himself, not discerning the body of the Lord.” (I Corinthians xi, 23-29)