"O tower not of ivory": Rosenberg points out that this image inverts and thus parodies both the Litany of the Blessed Virgin and the Song of Solomon 7:4: "Thy neck is as a tower of ivory."
According to John D. Rosenberg, "Libitina is the Goddess of gardens, voluptuous pleasures, fertility, and death --the Roman counterpart of the Greek god Priapus."
"Thalassian" = born of the sea, i.e. Venus. Swinburne named his late autobiographical poem, which appeared in Songs of the Springtides (1880), "Thalassius," since he felt that he, too, was in a sense born of the sea.
The beautiful tyrant is Nero, who fiddled — actually, played the lyre — while Rome burned.
Vestal: All the temples served by Vestal Virgins in ancient rome are gone.
Alciphron: a Greek rhetorician and author of letters supposedly written by celebrated courtesans (Rosenberg 154n). Walter Savage Landor wrote a once well-known poem entitled "Alciphron and Leucippe," which is available online.
Arisbe: here one of the wives of King Priam of Troy whom he married before Hecuba. In The Iliad, the word also appears twice as a place name. (For additional information see the entry in fact-index.com.)
visible god: A contrast to the Judeao-Christian god, who is not visible to us and must be taken on faith.
Ipsithilla: the lover to whom Catullus addresses poem 32 of the Carmine: In Peter Whigam's translation (Penguin, 1967) the poem begins:
Call me to you
we'll make love
my gold and jewels
my treasure trove
my sweet Ipsíthilla.
Dindymus: "The centre of the worship of the Phrygian kube/lh or kubh/bh, was in very ancient times the town of Pessinus in Galatian Phrygia, at the foot of Mt. Dindymus, from which the goddess [Cybele] received the name Dindymene. . . . The especial worship of Cybele was conducted by emasculated priests called Galli (or, as in vv. 12 and 34, with reference to their physical condition, Gallū)" (source).
The lines "As the rod to a serpent that hisses/As the serpent again to a rod" refer to several passages in the Bible. Rosenberg (157n) points to the passage in Exodus 7:9 when God instructs Aaron, "Take thy rod, and cast it before Pharoh, and it shall become a serpent." In the Bible, Aaron's Rod (which provided D. H. Lawrence with the title of one of his novels) represents a true miracle caused by God as opposed to the false magic of Pharoah's priests and magicians. According to the online International Standard Bible Encyclopedia Aaron's rod appears a second time in the same part of the Bible:
Immediately after the incidents connected with the rebellion of Korah, Dathan and Abiram against the leadership of Moses and the priestly primacy of Aaron (Nu 16), it became necessary to indicate and emphasize the Divine appointment of Aaron. Therefore, at the command of Yahweh, Moses directs that twelve almond rods, one for each tribe with the prince's name engraved thereon, be placed within the Tent of the Testimony. When Moses entered the tent the following day, he found that Aaron's rod had budded, blossomed and borne fruit, "the three stages of vegetable life being thus simultaneously visible." When the miraculous sign was seen by the people, they accepted it as final; nor was there ever again any question of Aaron's priestly right. The rod was kept "before the testimony" in the sanctuary ever after as a token of the Divine will (Nu 17:10)
Aphaca and Lampsacus: According to The Ecclesiatical History of Salaminius Hermias Sozemenus (born c. 400), the emperor Constantine destroyed the temple at Aphaca dedicated the Venus. See below Swinburne's quoted passage from Catullus, which cites the connection between Lampsacus and Priapus, who was "a god of fertility, protector of horticulture and viticulture . . . mainly known for his huge virile member" (Carlos Parada's mythology site, from which I have taken the previous quotation, contains additional information and images).
Cotytto, a Thracian goddess worshipped in particularly licentious rites, appears in Milton's Comus:
Goddesse of Nocturnal sport
Dark vaild Cotytto, t' whom the secret flame
Of mid-night Torches burns; mysterious Dame
That ne're art call'd, but when the Dragon woom
Of Stygian darknes spets her thickest gloom,
And makes one blot of all the ayr. [ll. 129-36; text transcribed by Judith Bass at U. of Oregon site]
Astarte and Ashtaroth were Middle-Eastern analogues to Venus (or Aphrodite) whose worship entailed male castration or human sacrifice. Rossetti's 1877 painting Astarte Syriaca is also known as Venus Astarte. Here as throughout much of the poem, Swinburne emphasizes the more painful, even crueler, aspects of physical love and desire.
But while men slept, his enemy came and sowed tares among the wheat, and went his way. But when the blade was sprung up, and brought forth fruit, then appeared the tares also. So the servants of the householder came and said unto him, Sir, didst not thou sow good seed in thy field? from whence then hath it tares? He said unto them, An enemy hath done this. The servants said unto him, Wilt thou then that we go and gather them up? But he said, Nay; lest while ye gather up the tares, ye root up also the wheat with them. Let both grow together until the harvest: and in the time of harvest I will say to the reapers, Gather ye together first the tares, and bind them in bundles to burn them: but gather the wheat into my barn.
Another parable put he forth unto them, saying, The kingdom of heaven is like to a grain of mustard seed, which a man took, and sowed in his field: Which indeed is the least of all seeds: but when it is grown, it is the greatest among herbs, and becometh a tree, so that the birds of the air come and lodge in the branches thereof.
Another parable spake he unto them; The kingdom of heaven is like unto leaven, which a woman took, and hid in three measures of meal, till the whole was leavened.
All these things spake Jesus unto the multitude in parables; and without a parable spake he not unto them: That it might be fulfilled which was spoken by the prophet, saying, I will open my mouth in parables; I will utter things which have been kept secret from the foundation of the world. Then Jesus sent the multitude away, and went into the house: and his disciples came unto him, saying, Declare unto us the parable of the tares of the field. He answered and said unto them, He that soweth the good seed is the Son of man; The field is the world; the good seed are the children of the kingdom; but the tares are the children of the wicked one; The enemy that sowed them is the devil; the harvest is the end of the world; and the reapers are the angels. As therefore the tares are gathered and burned in the fire; so shall it be in the end of this world.
Swinburne typically here both shows his close knowledge of scripture and parodies it, casting doubt on the truths of Christianity.
Catullus, Carm. xviii [Swinburne's note in Latin]: Here, in Whigam's translation, is all of poem 18:
I dedicate, I consecrate this grove to thee,
Priapus, whose home and woodlands are at Lampsacus;
there, among the coastal cities of the Hellespont,
they chiefly worship thee:
their shores are rich in oysters!
Oysters are mentioned, of course, because legend had it that they promoted both sexual desire and potency.
The Poems of Algernon Charles Swinburne, 6 volumes, London: Chatto & Windus, 1904.
Swinburne: Selected Poetry and Prose. Ed. John D. Rosenberg. New York: Modern Library, 1968.