CHAPTER VIII. 



CEMENTS, MORTARS, PAINTS AND GLUES. 



Cement and Mortar. 



CEMENTS FOR IRON. i. Sal ammoniac, 2 ozs. ; suL- 

 phur, ioz.; clean iron borings or filings reduced to pow- 

 der, 12 Ibs. ; water enough to form a thin paste. 



2. Sal ammoniac, 2 ozs.; iron filings, 8 Ibs.; sufficient 

 water. 



3. i or 2 parts of sal ammoniac to 100 of iron filings. 

 When the work is required to set quickly, increase the sal 

 ammoniac slightly and add a small amount of sulphur. 



4. Iron filings, 4 Ibs.; pipe clay, 2 Ibs.; powdered pot- 

 sherds, 1 1 Ibs. ; make into a paste with moderately strong 

 brine. 



5. Equal parts of red and white lead, mixed into a paste 

 with boiled linseed oil. Used for making metallic joints of 

 all kinds. 



6. To 4 or 5 parts of clay, thoroughly dried and pulver- 

 ized, add 2 parts of iron filings free from oxide, i part of 

 peroxide of manganese, ^ of sea salt and ^ of borax 

 mix well and reduce to a thick paste with water. Use Im- 

 mediately. Expose to warmth, gradually increasing al- 

 most to white heat. 



7. Sifted coal ashes 2 parts and common salt i part. 

 Add water enough to make a paste and apply at once. This 

 is also good for stoves and boilers, as it stands heat. 



BOILER CEMENTS. i. Chalk, 60 parts ; lime and salt, 

 of each, 20 parts ; sharp sand, 10 parts ; blue or red clay 



(69) 



