The following entry appears on p. 553 of the 1912 edition of “An Encyclopaedia of Freemasonry and Its Kindred Sciences” by Albert G. Mackey.
The triple triangle, or the pentalpha of Pythagoras, is so called from the Greek words pente, meaning five, and alpha, the letter A, because in its configuration it presents the form of that letter in five different positions. It was a doctrine of Pythagoras, that all things proceeded from numbers, and the number five, as being formed by the union of the first odd and the first even, was deemed of peculiar value; and therefore, Cornelius Agrippa says (Philos. Occult.) of this figure, that, “by virtue of the number five, it has great command over evil spirits because of its five double triangles and its five acute angles within and its five obtuse angles without, so that this interior pentangle contains in it many great mysteries.”
The disciples of Pythagoras, who were indeed its real inventors, placed within each of its interior angles one of the letters of the Greek word ΥΓΙΕΙΑ or the Latin one SALUS, both of which signify health; and thus it was made the talisman of health. They placed it at the beginning of their epistles as a greeting to invoke secure health to their correspondent. But its use was not confined to the disciples of Pythagoras. As a talisman, it was employed all over the East as a charm to resist evil spirits. Moné says that it has been found in Egypt on the statue of the god Anubis. Lord Brougham says, in his Italy, that it was used by Antiochus Epiphanes, and a writer in Notes and Queries (3 Ser., ix, 511) says that he has found it on the coins of Lysimmachus. On old British and Gaulish coins it is often seen beneath the feet of the sacred and mythical horse, which was the ensign of the ancient Saxons.
The Druids wore it on their sandals as a symbol of Deity, and hence the Germans call the figure “Druttenfuss,” a word originally signifying Druid’s foot, but which, in the gradual corruptions of language, is now made to mean Witche’s foot. Even at the present day it retains its hold upon the minds of the common people of Germany, and is drawn on or affixed to cradles, thresholds of houses, and stable-doors, to keep off witches and elves.
The early Christians referred it to the five wounds of the Savior, because, when properly inscribed upon the representation of a human body, the five points will respectively extend to and touch the side, the two hands, and the two feet.
The Medieval Freemasons considered it a symbol of deep wisdom, and it is found among the architectural ornaments of most of the ecclesiastical edifices of the Middle Ages.
But as a Masonic symbol it peculiarly claims attention from the fact that it forms the outlines of the five-pointed star, which is typical of the bond of brotherly love that unites the whole Fraternity. It is in this view that the pentalpha or triple triangle is referred to in Masonic symbolism as representing the intimate union which existed between our three ancient Grand Masters, and which is commemorated by the living pentalpha at the closing of a Royal Arch Chapter.
Many writers have confounded the pentalpha with the Seal of Solomon, or Shield of David. This error is almost inexcusable in Oliver, who constantly commits it, because his Masonic and archeological researches should have taught him the difference. Solomon’s Seal being a double, interlaced triangle, whose form gives the outline of a star of six points.
The full text of the 1912 edition of Mackey’s “An Encyclopaedia of Freemasonry and Its Kindred Sciences” may be found at:Mackey’s Encyclopaedia of Freemasonry: Volume I
Mackey’s Encyclopaedia of Freemasonry: Volume II