Farewell, O sun, Cleombrotus exclaim'd,
Then plung'd from off a height beneath the sea;
Stung by pain, of no disgrace ashamed,
But mov'd by Plato's high philosophy.

This is alluded to by Juvenal—

Provida Pompeio dederat Campania febres
Optandas: sed multæ urbes et publica vota
Vicerunt. Igitur Fortuna ipsius et Urbis,
Servatum victo caput abstulit.—Sat. x. 283.

Pompey's second wife was Julia, the daughter of Julius Cæsar; she died the year before the death of Crassus, in Parthia. Virgil speaks of Cæsar and Pompey as relations, using the same expression (socer) as Cicero—

Aggeribus socer Alpinis atque arce Monœci
Descendens, gener adversis instructus Eois.—Æn. vi. 830.

This idea is beautifully expanded by Byron:—

Yet if, as holiest men have deem'd, there be
A land of souls beyond that sable shore
To shame the doctrine of the Sadducee
And sophist, madly vain of dubious lore,
How sweet it were in concert to adore
With those who made our mortal labours light,
To hear each voice we fear'd to hear no more,
Behold each mighty shade reveal'd to sight,
The Bactrian, Samian sage, and all who taught the right.

Childe Harold, ii. 8.

The epitaph in the original is,—

Ὥ ξεῖν᾽ ἀγγεῖλον Λακεδαιμονίοις ὅτι τῇδε
κείμεθα, τοῖς κείνων πειθόμενοι νομίμοις.