our mandrake.  The Romans of old had their rock-breaking plant called “saxifraga” or sassafras; [6] and we know in later times how the granulated roots of our white meadow saxifrage (Saxifraga granulata), resembling small stones, were supposed to indicate its efficacy in the cure of calculous complaints.  Hence one of its names, stonebreak.  The stony seeds of the gromwell were, also, used in cases of stone—­a plant formerly known as lichwale, or, as in a MS. of the fifteenth century, lythewale, stone-switch. [7]

In accordance, also, with the same principle it was once generally believed that the seeds of ferns were of an invisible sort, and hence, by a transference of properties, it came to be admitted that the possessor of fern-seed could likewise be invisible—­a notion which obtained an extensive currency on the Continent.  As special good-luck was said to attend the individual who succeeded in obtaining this mystic seed, it was eagerly sought for—­Midsummer Eve being one of the occasions when it could be most easily procured.  Thus Grimm, in his “Teutonic Mythology,” [8] relates how a man in Westphalia was looking on Midsummer night for a foal he had lost, and happened to pass through a meadow just as the fern-seed was ripening, so that it fell into his shoes.  In the morning he went home, walked into the sitting-room and sat down, but thought it strange that neither his wife nor any of the family took the least notice of him.  “I have not found the foal,” said he.  Thereupon everybody in the room started and looked alarmed, for they heard his voice but saw him not.  His wife then called him, thinking he must have hid himself, but he only replied, “Why do you call me?  Here I am right before you.”  At last he became aware that he was invisible, and, remembering how he had walked in the meadow on the preceding evening, it struck him that he might possibly have fern-seed in his shoes.  So he took them off, and as he shook them the fern-seed dropped out, and he was no longer invisible.  There are numerous stories of this kind; and, according to Dr. Kuhn, one method for obtaining the fern-seed was, at the summer solstice, to shoot at the sun when it had attained its midday height.  If this were done, three drops of blood would fall, which were to be gathered up and preserved—­this being the fern-seed.  In Bohemia, [9] on old St. John’s Night (July 8), one must lay a communion chalice-cloth under the fern, and collect the seed which will fall before sunrise.  Among some of the scattered allusions to this piece of folk-lore in the literature of our own country, may be mentioned one by Shakespeare in “I Henry IV.” (ii. 1):—­

“Gadshill.  We have the receipt of fern-seed, we walk invisible——­[10]

“Chamberlain.  Nay, by my faith, I think you are more beholding
to the night than to fern-seed for your walking invisible.”

In Ben Jonson’s “New Inn” (i. 1), it is thus noticed:—­