at Shrovetide, white besoms with white handles are tied to the cows’ horns; and, in the rites connected with the Midsummer fires kept up in different parts of the country, the besom holds a prominent place.  In Bohemia, for instance, the young men collect for some weeks beforehand as many worn-out brooms as they can lay their hands on.  These, after dipping in tar, they light—­running with them from one bonfire to another—­and when burnt out they are placed in the fields as charms against blight.[13] The large ragwort—­known in Ireland as the “fairies’ horse”—­has long been sought for by witches when taking their midnight journeys.  Burns, in his “Address to the Deil,” makes his witches “skim the muirs and dizzy crags” on “rag-bred nags” with “wicked speed.”  The same legendary belief prevails in Cornwall, in connection with the Castle Peak, a high rock to the south of the Logan stone.  Here, writes Mr. Hunt,[14] “many a man, and woman too, now quietly sleeping in the churchyard of St. Levan, would, had they the power, attest to have seen the witches flying into the Castle Peak on moonlight nights, mounted on the stems of the ragwort.”  Amongst other plants used for a similar purpose were the bulrush and reed, in connection with-which may be quoted the Irish tale of the rushes and cornstalks that “turn into horses the moment you bestride them[15].”  In Germany[16] witches were said to use hay for transporting themselves through the air.

When engaged in their various occupations they often considered it expedient to escape detection by assuming invisibility, and for this object sought the assistance of certain plants, such as the fern-seed[17].  In Sweden, hazel-nuts were supposed to have the power of making invisible, and it may be remembered how in one of Andersen’s stories the elfin princess has the faculty of vanishing at will, by putting a wand in her mouth.[18] But these were not the only plants supposed to confer invisibility, for German folk-lore tells us how the far-famed luck-flower was endowed with the same wonderful property; and by the ancients the heliotrope was credited with a similar virtue, but which Boccaccio, in his humorous tale of Calandrino in the “Decameron,” applies to the so-called stone.  “Heliotrope is a stone of such extraordinary virtue that the bearer of it is effectually concealed from the sight of all present.”

Dante in his “Inferno,” xxiv. 92, further alludes to it: 

  “Amid this dread exuberance of woe
  Ran naked spirits winged with horrid fear,
  Nor hope had they of crevice where to hide,
  Or heliotrope to charm them out of view.”

In the same way the agate was said to render a person invisible, and to turn the swords of foes against themselves.[19] The Swiss peasants affirm that the Ascension Day wreaths of the amaranth make the wearer invisible, and in the Tyrol the mistletoe is credited with this property.