256 ART OF BUILDING. 



lathes nailed to pieces of wood ctMedfurrings, leaving a 

 space between the wall and plastering. This is the com- 

 mon practice in this country and is founded upon the fol- 

 lowing principles of heat. Brick and stone being bad 

 conductors of heat, stone or brick houses are warm in 

 the winter and cool in the summer, and if warm air 

 (which is always charged with moisture) comes in 

 contact with a colder body, as stone or brick, the moist- 

 ure is condensed upon the cold body in the form of wa- 

 ter : now apply the principles to a room in a stone or 

 brick house, the moisture of the room is condensed by 

 the cold walls. If a confined space of air is left between 

 the wall and plastering, air being a bad conductor of heat, 

 the cold of the brick or stone does not reach the plaster- 

 ing, therefore such houses are never damp because 

 the moisture can never come through the walls, if pro- 

 perly constructed. 



White-washing and coloring is another part of a ma- 

 son's work, and consists in laying a thin coat of lime upon 

 any surface, either its natural color, white, or any other. 

 Lime washes for stone, brick, or plastering should be 

 made by slacking lime with pure fresh water, as salt wa- 

 ter would cause it to exfoliate or peal off, and a small 

 quantity of lampblack should be added, (previously kill- 

 ed in vinegar) as this deprives the lime of its yellow tint. 

 Where wood work is to be washed, the lime should be 

 slacked with ?alt water, as this gives it a better set than 

 fresh water would, and will prevent its pealing off. 



Thus, we have gone through with a practical explana- 

 tion of the principal materials used !>v the mason, and a 

 short illustration of some of their uses , our object has 

 been solely to explain the rationale of their operations, to 

 give a few of the whys and whcnfures : if these are pro- 

 perly understood by the masons of our country, we willingjf 

 leave the manual part of their art to the well known in- 

 genuity of our countrymen, with a sure pledge that our 

 country will not be wanting in monuments of their skill 

 and intelligence. 



BOSTON: 

 PUBLISHED BY CARTER, II E X D E E &. BAB COCK. 



