“According to Peter of Capua, the Cross and the Church; but Saint Melito says the saints.  According to the monk of Clairvaux, it is the false doctrine of the Jews and heretics; and as to the drops of resin, they are Christ’s tears, if we may believe Saint Ambrose,” replied the Abbe Plomb.

“And even so, our cathedral remains incomplete.  We are but feeling our way, without logical sequence.  I admit that at the entrance we must plant the purifying hyssop in the place of the holy-water vessel; but with what can we build the walls unless we accept the alternative of a real church having walls but unfinished?”

“Take the figurative sense of the walls and translate that; the great walls are representative of the four Evangelists, Can you find plants for them?”

Durtal shook his head.  “The Evangelists are, of course, symbolized in the fauna of mysticism by the animals of the Tetramorph; the twelve apostles have their synonyms in the category of gems, and two of the Evangelists are naturally to be found there:  Saint John is associated with the emerald, the emblem of purity and faith; Saint Matthew with the chrysolite, the emblem of wisdom and watchfulness; but none, so far as I know, has found a representative among either trees or flowers.  And yet, to be sure, Saint John has the sun-flower, signifying divine inspiration; for he is represented in a window in the church of Saint Remy at Reims, his head crowned with a nimbus surmounted by two of these flowers.”

“Saint Mark, too, has a plant—­the tansy, so named in the Middle Ages.”

“The tansy?”

“Yes; a bitter, aromatic plant with yellow flowers, which grows in stony ground, and is used in medicine as an anti-spasmodic.  Like Saint George’s herb, it is used in nervous maladies, the intercession of Saint Mark being, it would seem, of sovereign efficacy.

“As to Saint Luke, he may be represented by clumps of mignonette, for Sister Emmerich tells us that while he was a physician it was his favourite remedy.  He macerated mignonette in palm oil, and after blessing it, applied the unction in the form of a cross on the brow and mouth of his patients; in other cases he used the dried plant in an infusion.

“Only Saint Matthew remains; but here I give in, for I know of no vegetable species that can reasonably be assigned to him.”

“Nay, do not think it hopeless,” cried the Abbe Plomb.  “A mediaeval legend tells us that balms exuded from his tomb; hence he was represented as holding a branch of cinnamon, symbolical of the fragrance of virtue, says Saint Melito.”

“Well, it would be better to accept the real walls of a church, making use of the structure, and limiting ourselves to completing the idea by details borrowed from the symbolism of flowers.”

“And the sacristy?” suggested the Abbe Gevresin.