312 Progress of Foreign Science. 



for water- mortars, which is of too little interest in this king- 

 dom for us to copy, he next presents us with the following table 

 of analyses of hydraulic limestones. 



Carbonate of lime 0.900 0.858 0.892 0.890 0.890 0.825 — 0.792 0.765 O.800 0.840 



magnesia O.050 0.004 00.30 0.020 0.020 0.041 — 0.025 0.030 O.OlS 



iron . . 0.062 — 0.060 0.030 



C Silica. . . . — 0.06.0 0.116 0.170 0.100 



^1 Alumina. . . 0.050 0.054 0.078 0.090 O.090 0.134 — 0.038 0.036 0.010 0.050 



5 ) Oxide of iron . — O.olO 



(Charcoal. . . 0.022 — O.020 



1.000 1.000 1.000 1.000 I.OOO 1.000 — 1.000 0.992 l.OOS 1.000 



The first five are called moderately hydraulic ; the last six very 

 hydraulic. 



No. (1.) Limestone of Vougy (Loire,) between Roanne and 

 and Chaulieu ; sublamellar, yellowish, full of ammonites, and 

 other shells. It gives a very good lime, which sets in water. 

 (2.) Limestone of St. Germain, (Ain,) compact, of a deep grey, 

 veined with white limestone, lamellar, and penetrated with 

 gryphites. It is employed at Lyons, for water-works. (3.) 

 Limestone of Chaunay, near Macon ; compact, in fine grains, 

 yellowish-white ; it is of the secondary formation, and is em- 

 ployed in the fabrication of a lime, which is hydraulic. (4.) 

 Limestone of Digna (Jura) ; compact, penetrated with plates of 

 limestone, and having imbedded a great number of gryphites, 

 of a very deep grey. It produces lime which takes a good 

 hold, and may be considered as hydraulic. (5.) Limestone, 

 which accompanies the preceding, and which enjoys the same 

 properties ; compact, in grains nearly earthy, of a bright grey 

 colour. (6.) Secondary limestone of Nismes (Gard) ; compact, 

 yellowish-grey ; yields a hydraulic lime, which passes in the 

 country for being of excellent quality. (7.) Lime of Lezoux, 

 (Puy de Dome,) fabricated from a marly fresh-water limestone. 

 It is called excellent. It produces an abundant jelly, with 

 acids. (8.) Compact limestone, the locality of which is un- 

 known. It gives a very good hydraulic lime. (9) Second- 

 ary limestone of Metz (Moselle) ; compact, in grains almost 

 earthy, of a bluish grey, more or less deep. The lime which 

 it produces is known to be hydraulic. (10.) Marly limestone 

 of Senonches, near Dreux (Eure et Loire) ; compact, very ten- 

 der, crushes between the fingers, absorbs water very readily. 

 It forms a paste with this liquid, nearly like clay, but it does 

 not fall into powder, when calcined. This lime is very cele- 

 brated, and is much employed at Paris. (11.) Mixture of four 

 parts of the chalk of Meudon, and one part of the clay of Passy, 

 in volume, which M. Saint-Leger employs to make artificial 

 hydraulic lime, in the manufacture of it, established near the 

 military school. The government uses at present only the lime 



