Geological Collections. 189 



long-continued heat. The pieces, he informs me, are part of the bottom of a 

 tub, which held about 130 gallons, and which had been in use in his laboratory 

 about three years and a half, and almost constantly worked for boiling a 

 weak solution of common salt, generally with an open steam-pipe, and 

 sometimes, though rarely, with a coil : the temperature was seldom higher 

 than 2J6° or 220°, and the vessel was lined with tin, rolled into sheets, 

 about the sixteenth of an inch thick, and nailed to the inside : the joints, 

 however, were not so good as to prevent the liquid from getting between 

 the metal and the wood. Mr May states also, that he had long since 

 remarked, that on making extracts with steam, of very moderate pressure, 

 all the apparent effects of burning might be produced, but that he was not 

 prepared to find so complete a carbonization of wood by steam ; the vessel 

 was made partly of fir and partly of ash, the former of which was most 

 perfectly reduced to the state of charcoal. 



Fossil Skull of an Ox, recently discovered in Caithness. (Commu- 

 nicated by Alexander Miller, Esq. of Wick.) — There was lately found, in 

 a marl p't, at Tlu:umster, in this county, (Caithness,) the skull of an animal 

 of the ox genus. It was imbedded in the marl at the depth of eight or ten 

 feet from the surface. Through the kindness of my friend, Dr Henderson, 

 of this place, I was favoured with the subjoined measurements. 



Distaiice between the roots of the horns, 9 inches. 



Distance fi-om line between the horns to the orbits, 6 inches. 



Length of sloughs of horns remaining, 1 foot. 



Diameter of roots of ditto, 4 inches. 



The nasal bones are all wanting ; and the tips of the sloughs of the horns 

 are gone, the horns being also wanting. They curved outwards and forwards, 

 and were in all probability at least two feet long. The distance between 

 their tips perhaps 24 or 30 inches Sd January, 1831. 



Fusible Mineral Compounds. — Mons. Berikier This indefatigable 



chemist has instituted an elaborate examination of the scoriae of various 

 lead works, chiefly those of England, with a view to determine their 

 value and the mode of their formation. These have led him to some very 

 curious results, some of which may probably become highly useful in 

 the arts. He finds that the fluorides, chlorides, and even the sulphides, 

 form with each other, in most cases, and with certain oxides and salts, 

 combinations which are extremely fusible. " These combhiations are 

 in general very weak, since water decomposes them completely, when one 

 of the elementary principles is soluble. Analogous compounds are found 

 in nature, such as the topaz, picnite, certain micas, apatite, the chlorophps- 

 phate, and the chloroarseniate of lead ; but some of them are infusible." 

 We quote the conclusion of the paper as very interesting: — Several of 

 the fusible compounds treated of in this article may be employed for founding 

 statues, vases, has reliefs, medals, and other ornaments, which, would thus 

 imitate perfectly the works of the sculptor, but which would be much 

 cheaper, and which would have, over plaster casts, the great advantage of 

 bearing exposure to the air as well as marble. Experience would soon 

 teach the best compositions. Those which seem to me likely to succeed 

 are the following : — 



80 Calcined plaster of Paris + 20 Fluor spar 

 70 Sulphate of barytes + 30 Fluor spar 



90 Sulphate of lead + 10 Fluor spar 



25 Calcined plaster, 20 sulphate of barytes, 40 sulphate of lead, 

 15 fluor spar. 



