366 Dr. J. W. Griffith on the Composition of 



difficult, is preferable, as there is less liability of the water of 

 the refrigerator leaking into the bore. 



Select a very sound and malleable cylinder of platina, of 

 about three-eighths of an inch in thickness, perforate it by 

 drilling in a lathe, so that the perforation may be concentric 

 with the axis. A drill between one-sixteenth and one-eighth 

 of an inch in diameter may be employed. In the next place, 

 the cylinder may be elongated by the wire-drawing process 

 until the proper reduction of metallic thickness is effected, the 

 diameter of the bore being prevented from undergoing an 

 undue diminution by the timely introduction of a steel wire. 



Of course the metal must be annealed as often as it har- 

 dens, by drawing. For this purpose a much higher tempe- 

 rature is necessary in the case of platinum, than in that of 

 either copper, silver, or gold. 



The annealing is best performed by the hydro-oxygen 

 flame. If charcoal be used, the greatest care must be taken 

 to have the fireplace clean. 



Agreeably to a trial made last spring, palladium may be 

 used as a solder for platinum ; and as it is nearly as difficult 

 to fuse as this metal, it is of course for that purpose preferable 

 to gold, where great heat is to be resisted. No doubt by em- 

 ploying palladium to solder the exterior juncture of the double 

 drawn tubes above mentioned, they might answer as well 

 nearly as when constructed of solid platinum. 



This idea has been verified by a successful trial : and, 

 moreover, silver has been successfully employed to solder the 

 portions of the tubes, protected from heating by being within 

 the cavity occupied by water. The portions which protrude 

 beyond the brass box (see fig. 1) may be left unsoldered. 



LIX. Oti the Coviposition of the Bile of the Sheep. By J.'W, 

 Griffith, M.D.^ F.L.S., Physician to the Finshury Dis- 

 pensary^. 



T^HE following analysis was made with the view of compa- 

 -*■ ring the composition of this fluid with that of the biliary 

 secretion in other animals ; the conditions under which the 

 analyses of the bile in them were performed have therefore 

 been observed as closely as possible. 



The bile in a perfectly fresh state was evaporated to dry- 

 ness in a water-bath, the residue powdered and exhausted 

 with alcohol of 840 specific gravity, the solution filtered, and 

 the alcohol distilled off at 212° F. ; the dry residue was next 

 powdered, dissolved in absolute alcohol, the solution filtered 

 * Communicated by the Author. 



