544 REVIEWS 



The Classification of the Crystalline Cements. Amer. Geologist, VoL 



XXIX, pp. 146-154, March, 1902. Reprinted in Cement, Vol. Ill, 



pp. 1 09-1 14, May, 1902. Reprinted in part in Engineering News,. 



Vol. XLVI, p. 354, May 1, 1902. 



A classification of cementing materials, with notes on raw materials, technology, 



and the properties of the various products. The grouping offered is as follows : 



I. Simple cements; including those materials which are produced by the expulsion 

 of a liquid or gas from the raw material; and whose set is due to the simple reab- 

 sorption of the same liquid or gas and a reassumption of original composition. 



la. Hydrate cements; set due to reabsorption of water. Plaster-of-Paris, cement 

 plasters, Keene's cement, Parian cement, etc. 



lb. Carbonate cements; set due to reabsorption of carbon dioxide. Limes, mag- 

 nesian limes, etc. 



II. Complex cements; including those cementing materials whose set is due to the 

 formation of new compounds during manufacture or use. 



Ha. Silicate cements; set due to the formation of silicates. Hydraulic limes, natural 

 cements, Portland cement, pozzuolanic cements. 



lib. Oxychloride cements; set due to the formation of oxychlorides. Sorel stone, 

 etc. 



Frear, William, The Use of Lime upon Pennsylvania Soils. Bulletin 61, 

 Pa. Dept. Agriculture. 170 pp., 1900. 



Principally a discussion of lime in its relation to agriculture, but contains also very 

 satisfactory accounts of limestones (in general) and lime-burning, with 273 analyses- 

 of Pennsylvania limestones, mostly compiled from reports of the Second Geological 

 Survey of that state. 



Harris, G. D., and Veatch, A. C. General Geology (of Louisiana). Geo. 

 logical Survey of Louisiana, Report for 1899. Pp. 55-138, Pis. i-ii, Figs- 

 2-5, geological maps. 



Report on the stratigraphic and economic geology of the state. The matter of 

 clays, limestones, sandstones, and gravels (pp. 127-132) is here summarized. 



Good brick clays are common in the alluvium and yellow loam, and are also 

 found at several places in the hill-lands. The Eocene clays commonly lack plasticity, 

 though some beds occur which will make a fair quality of earthenware. Good potter's 

 clay occurs in the Lignitic, near Robeline, where it has been utilized. The clays of 

 the Grand Gulf hills seem to be more promising than any others in the state, good 

 exposures occurring in Catahoula and Vernon parishes. 



The sandstones of the state are of two classes ; the ferruginous sandstones of the 

 Eocene and Lafayette, and the siliceous sandstones of the Grand Gulf. The former 

 are widely distributed, but are unimportant as structural materials. The siliceous 

 Grand Gulf sandstones are of greater value, and have been used for jetty work and 

 railroad ballast. 



Limestones of Cretaceous age outcrop at Winnfield, Coochie Brake, and Bayou 

 Chicot. The first is a pure limestone, which may be used for lime, but not for building 

 stone. The other two are of greater value for structural purposes. Limestone con- 

 cretions occurring in the Tertiary are of local importance for lime or road metal. 



