LIME 



CALCIUM CARBONATE 



INDIAN LIMESTONES 



Stucco. 



White Mortar. 



Chunam. 

 Composition. 



Whitewash. 



Carved Cement. 



Glutinous 

 Cements. 



Bice. 



Flour Gluten. 



Resinous Lac. 



Cutlers' Cement. 



their adhesive power is diminished by mixture with sand. When used 

 as a stucco the sand employed must be perfectly free from loam, and the 

 surface must not be painted over (if that be so desired) until the cement 

 has been thoroughly dry for some months. 



It may further be added that if Portland cements have more than 

 4 per cent, magnesia they rapidly decompose when kept under water. 

 A cement with a basis of white magnesia in place of clay is sometimes 

 known as " White Mortar." There are large deposits of magnesite and 

 of magnesium limestones (dolomites), especially near Salem in South 

 India, and these it is understood have recently been taken advantage of 

 by the Madras Portland Cement Company in the preparation of a cheap, 

 easily applied and rapidly drying plaster that takes a fine polish. In the 

 public press it is not uncommon to read the certificates of " Arbuthnot's 

 Portland Cement " as being " equal to the best-known brands of English 

 Portland Cement." Mr. C. S. Middlemiss wrote in 1896 a most interesting 

 report on the magnesite areas of the Chalk Hills near Salem (Agri. 

 Ledg., 1896, No. 15). Papers written by James Cleghorn (Ind, and East. 

 Engin., May 1894, 320-1 ; 1898, ii., 210-11 ; iii., 32-3 ; iv., 28, etc.) will 

 also be found to contain much useful information regarding magnesian 

 cements. [Cf. Blount and Bloxam, Chem. for Engin. and Manuf., 1900, 

 132-42 ; Min. Indust. in U.S.A., 1900, 75, 82 ; Gilmore, Hydr. Cements, 

 1-334, etc.] 



Chunam. Incidental mention has already been made of the fact that 

 an admirable polishing and exceedingly strong cement (sometimes spoker 

 of as chundm) is made in several parts of India. There are various methc 

 of preparing this substance, but these all practically agree in the cii 

 cumstance that some saccharine substance is combined with the Iii 

 as well as powdered marble, plaster of Paris or steatite. The su 

 most commonly employed for this purpose is the jaggery obtained fror 

 the cocoanut palm. The milk of that palm is also mixed with lime ir 

 the preparation of a very superior whitewash. It is believed that the 

 sugar promotes the solubility of the lime, thus allowing of a finer anc 

 more complete state of division. 



A special art of some parts of India, as, for example, in Bikanii 

 consists in carving cemented surfaces into rich floral designs that 

 may be subsequently gilded or painted. [Cf. Ind. Art at Delhi, 1903, 

 95-6.] 



Cement Materials. Lime or some of its salts (such as plaster of Paris) is 

 largely employed in combination with glutinous and resinous materials ii 

 the formation of cements. The rice-water is in India commonly mixe 

 with a certain percentage of pure lime in the preparation of a strong 

 cement which is employed to join the various parts of musical instruments 

 in place of glue. Instead of rice, the dough of fine flour may be kneaded 

 in water until gluten only remains. To this should then be added a 

 small quantity of pure lime. The cement thus prepared is largely used 

 for all forms of woodwork, and has the special merit of resisting damp. 

 It is generally known by the name suji. Lac combined with borax 

 forms a convenient cement to be used where exposure to water or 

 moisture is unavoidable. Cutlers' cement consists of rosin, bees'-wax 

 and brickdust and plaster of Paris, or simply rosin and plaster of 

 Paris. Dr. Fleming, in his Account of the Salt Range, says the Natives 

 use plaster of Paris, mixed with pure lime, to produce their finest 



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