168 THE CURIOUS LORE OF PRECIOUS STONES
At the laste he thought to make the light, For the Bridge to shine by nighte, With Carbuncle Stones, to make men wonder, With double reflexion above and under: Then new thought troubled his Minde Carbuncle Stones how he might finde;
where to find wise men and trewe, Which would for his interest pursue,
In seeking all the Worlde about, Plenty of Carbuncles to find out; For
this he took so mickle thought, That his satt flesh wasted nigh to
is scarcely necessary to add that the poor parson never realized his
dream, but the story shows how popular was the belief that carbuncles
or rubies shone with their own light.
luminous or phosphorescent stone, which has been named the Bologna
stone, is the subject of a treatise published by the physician Mentzel
in 1675.48 The writer describes various experiments made to
test the peculiar qualities of this mineral, which is partly a radiated
or crystalline sulphate of barytes, and phosphoresces when calcined. It
was sometimes called the "lunar stone" (lapis lunaris), because,
like the moon, it gave out in the darkness the light it received from
the sun. Mentzel also relates that the stone was first discovered, in
1604, by Vincenzio Casscioroli, an adept in alchemy, who believed that
it would be a great aid in the transmutation of the baser metals into
gold, on account of its solar quality. The place of its occurrence was
Monte Paterno, near
45 Norton's "Ordinall"; in Ashmole " Theatrum Chemieum Brit-annicum," London, 1652, p. 27.
48 Christiani Mentzelli, " Lapis Bononensis," Bilefeldia;, 1675.