536 Asphaltic Mastic, to Flooring, Roofing, [No. 139. 



destruction of some remains of fortifications, supposed to be of Roman 

 erection near Pyrimont about 45 years ago, so great was the tenacity 

 of the work, that it was not pulled down without the aid of gunpowder, 

 which circumstance led to an important discovery ; it was observed 

 that the cement resembled the asphaltic rock of Pyrimont, about five 

 miles North of Seyssel at the foot of the Eastern side of mount Jura, 

 on the right bank of the Rhone in the department de L'Ain. Several 

 applications of the substance were immediately made, and the experi- 

 ments on its properties as a cement for building masonry and keeping 

 out damp succeeded entirely, since which, the working of the material 

 has become of great importance. In the immediate vicinity of the 

 asphalte is obtained a peculiar kind of mineral pitch, which mixed 

 in certain proportions with the asphalte, forms the mastic, the subject 

 of this memoir. Mr. Claridge, an English gentleman, has taken out 

 a patent for it in England, and is most successfully bringing it into 

 general use under the sanction of the Commissioners of woods and 

 forests. 



The surface of the ground in the locality of its discovery is covered 

 by a molasse, consisting of silicious gravel and bitumen intercepted by 

 deep ravines. A mass of calcareous asphalte is situated between two 

 of the ravines, the external appearance of which is whitish, but inter- 

 nally it is of a deep brown color. The asphalte is equally diffused 

 throughout the rock, in some places more or less saturated, but in 

 others the calcareous matter is quite pure,* leading to the conclusion, 

 that the asphalte is ramified in veins in the mass under the molasse. 

 The calcareous asphalte is not stratified, fissures are seen intersecting 

 each other in all directions. Various are the opinions of its formation, 

 but the following is the most probable, — that it has been generated 

 by heat naturally acting on the bituminous matter below strata of 

 carbonate of lime ; some of the bitumen has passed up and mixed with 

 the lime, by nature adjusted in just such proportions as the lime would 

 absorb, thus has been effected by a natural force, what by art could 

 not have been, and it is this which renders this material so far superior 

 to any manufactured article. 



The resinous and sulphuric particles have passed up to the surface 

 and formed a crust, so that the inflammable qualities, as well as the 

 * Bulletin de la Societe Geologique de la France, Vol. vm. p. 138. 



