It was fabled that Castor and Pollux were alike immortal, that like day and night they periodically died, but that whenever one of the brothers expired the other was restored to life, thus sharing immortality between them. "There was," says Duncan, "an allusion to this tradition in the Roman horse-races, where a single rider galloped round the course mounted on one horse while he held another by the rein."[536] This ceremony becomes more interesting when we find that the cauchemar, the nightmare, or the blackmare used in England to be known as the "ephialtes".[537] That this ill-omened _hipha_, or hobby, was ill-boding Helena, seems somewhat to be confirmed by the custom in Cumberland of allotting to servants the years' allowance for horse-meat on St. Helen's, Eline's, or Elyn's day.[538] It is believed that horse meat is now taboo in Britain, because the eating of horse was so persistently denounced by Christianity as a heathen rite. [Illustration: FIG. 268.--British Altar. By kind permission of the authorities of the British Museum. [_To face page 479._] I have shown elsewhere some of the innumerable forms under which the fires of Elmo, or the heavenly Twain, were represented. In England it is evident that a pair of horses served as one form of expression, for among the treasures at the British Museum is an article which is thus described: "Bronze plate representing an altar decorated with blue, green, and red sunk enamels, and evidently unfinished, hence native work of the fourth or fifth century. Found in the river Thames, 1847". The principal decoration of this bijou altar--significantly 7 inches high--is two winged steeds supporting a demijohn, vase, or phial, the handles of which, in the form of [SS], are detached from the vase, but are emerging flame-like from the supporters' heads. The fact of these steeds appearing upon an "altar" is evidence of their sacred character, and one finds apparently the same two beasts delineated on a bucket, _vide_ Fig. 270. This so termed "barbaric production," discovered in an Aylesford gravel pit belonging to a gentleman curiously named Wagon, is attributed to the first century B.C., and has been compared unfavourably with the Etruscan bucket reproduced on page 474. The authorities of the British Museum comment upon it as follows: "The effect of barbaric imitation during two or three centuries may be appreciated by comparing the Etruscan _cista_ of the _fourth century_, with the Aylesford bucket of the _first century_ B.C. The first thing to be noticed is the absence from the latter of the heavy solid castings that form the feet and handle-attachments of the classical specimen. Such work was beyond the range of the British artificer, who was never successful with the human or animal form, but there is an evident desire to reproduce the salient features of the prototype. The solid uppermost band of the Etruscan