62 Geological Collections. 



it occurs. Its internal structure, as seen through the microscope, resemhles that 

 of the Coniferee. 



Fossil Bones discovered near Byde, Isle of Wight. — Mr. S. P. Pratt of Bath, 

 has, during the summer, discoveied near Ryde, in the Isle of Wight, several 

 fossil bones of mammalia and reptiles, thus bringing additional proofs of the ana- 

 logy that exists between these beds and those of Paris. Amongst the bones there 

 is a very ample under jaw of a ruminant animal allied to the genus Moschus ; 

 but which differs from any of the recent species by the great width of the coronary 

 process. There are also teeth of Anoplotherium and Pacelotherium, the bones of 

 two species of Chelonian reptiles, and the vertebra of a fish. They will be de- 

 scribed at the next meeting of the Geological Society. — J. E. Gray. 



JVew method of examining the structure of Fossil Vegetables, (described 

 by Mr. Nicol in Witham's Observations on Fossil Vegetables, p. 45, et seqq.) — 

 Let a thin slice be cut off from the fossil wood, in a direction perpendicular to the 

 length of its fibres. The slice thus obtained must be ground perfectly flat, and then 

 polished. The polished surface is to be cemented to a piece of plate or mirror 

 glass, a little larger than itself, and this may be done by means of Canada bal- 

 sam. A thin layer of that substance must be applied to the polished surface of 

 the slice, and also to one side of the glass. The slice and the glass are now to 

 be laid on any thin plate of metal, as a common fire-shovel, and gradually heated 

 over a slow fire, with a view to concentrate the balsam. In performing this opera- 

 tion, it will be requisite to prevent the heat from becoming so great as to throw 

 the balsam into a state of ebullition ; for, if air-bubbles be once formed in it, it 

 will be difficult to remove them, and if they are not removed, they will prevent 

 the complete adhesion of the two surfaces when applied to each other. The heat 

 of the shovel should never become so great that the fingers may not be held in 

 contact with it, without inconvenience, for a few seconds. With every precaution, 

 some few air-bubbles will sometimes make their appearance, but these may be 

 removed by a small piece of wood tapering to a point. When the balsam is 

 thought to be sufficiently concentrated, and all air-bubbles completely removed, 

 the slice and the glass may be taken from the shovel, and applied to each other. 

 A slight degree of pressure will be necessary to expel the superabundant balsam, 

 and this will be facilitated by gently sliding the one on the other. By this kind 

 of motion, any air that might have got entangled in the balsam, when the sur- 

 faces were brought into contact, will also be removed. 



When the whole is cooled down to the temperature of the air, and the balsam 

 becomes solid, that part of the balsam adhering to the surface of the glass sur- 

 rounding the slice should be removed by the point of a pen-knife ; and it may be 

 right to remark, that, in this operation, it will at once be seen whether the bal- 

 sam has undergone the requisite concentration. If, for instance, it has entirely 

 lost its sectility, and starts off in flakes before the knife, it will be found that the 

 slice and the glass will cohere so firmly, that, in the subsequent grinding, there 

 \yill be no risk of their separating from each other. If the balsam has not been 

 sufficiently concentrated, it will slide before the knife, and, in that case, the two 

 bodies will not adhere with sufficient firmness. A very few trials, however, will 

 enable any one to conduct the process with success ; and it may be right to add, 

 that, if the layer of balsam applied to the two surfaces be not too thick, its due 

 concentration may be accomplished in four or five minutes, provided the applica- 

 tion of the heat be duly regulated. 



. The slice must now be ground down to that degree of thinness which will per- 

 mit its structure to be seen by the help of a microscope. To facilitate this part of 

 the grinding, the lapidary will find it advantageous to fix the glass in a groove 

 made in a small piece of wood, of which half inch thick deal will answer the pur- 

 pose. The groove in the wood should be a little less deep than the thickness of 

 the glass, and the wood itself need not project more than half an inch beyoud 

 each side of the glass. 



