experiment a dangerous one. Early in 1786, Raspe
produced a brief but well-executed conspectus of the arrangement and
classification of the collection, and this was followed in 1791 by "A
Descriptive Catalogue," in which over fifteen thousand casts of ancient
and modern engraved gems, cameos, and intaglios from the most renowned
cabinets in Europe were enumerated and described in French and English.
The two quarto volumes are a monument of patient and highly skilled
industry, and they still fetch high prices. The elaborate introduction
prefixed to the work was dated from Edinburgh, April 16, 1790.

This laborious task completed, Raspe lost no time in applying himself
with renewed energy to mineralogical work. It was announced in the
_Scots Magazine_ for October 1791 that he had discovered in the extreme
north of Scotland, where he had been invited to search for minerals,
copper, lead, iron, manganese, and other valuable products of a similar
character. From Sutherland he brought specimens of the finest clay, and
reported a fine vein of heavy spar and "every symptom of coal." But in
Caithness lay the loadstone which had brought Raspe to Scotland. This
was no other than Sir John Sinclair of Ulbster, a benevolent gentleman
of an ingenious and inquiring disposition, who was anxious to exploit
the supposed mineral wealth of his barren Scottish possessions. With
him Raspe took up his abode for a considerable time at his spray-beaten
castle on the Pentland Firth, and there is a tradition, among members
of the family, of Sir John's unfailing appreciation of the wide
intelligence and facetious humour of Raspe's conversation. Sinclair had
some years previously discovered a small vein of yellow mundick on the
moor of Skinnet, four miles from Thurso. The Cornish miners he consulted
told him that the mundick was itself of no value, but a good sign of
the proximity of other valuable minerals. Mundick, said they, was a
good horseman, and always rode on a good load. He now employed Raspe to
examine the ground, not designing to mine it himself, but to let it out
to other capitalists in return for a royalty, should the investigation
justify his hopes. The necessary funds were put at Raspe's disposal,
and masses of bright, heavy material were brought to Thurso Castle as a
foretaste of what was coming. But when the time came for the fruition
of this golden promise, Raspe disappeared, and subsequent inquiries
revealed the deplorable fact th