lime.” When more water is added, the slaked lime becomes a paste, and this paste is mixed with sand to form a mortar.
Mortar for plaster work is usually composed of slaked lime mixed with sand and hair. The sand should be hard, sharp, gritty and free from all organic matter. Hair is used as a binder to increase cohesion and tenacity. For this purpose it should be long, strong, and free from grease or
other impurities. Ox hair is generally used, although sometimes adulterated with the short hair of horses. Substitutes for hair include manila fiber and sawdust.
Plaster of Paris is obtained from gypsum by gentle calcination. It is very soluble in water, and this fact renders it unfit for external use. It is, however, valuable for decorative details, for cornice, molds, and other enrichments, and is also used in several plastic mixtures. Plaster of Paris sets rapidly, acquiring full strength in a few hours.
Research has disclosed the fact that in essential
particulars the tools of plasterers in the early history of the craft were identical in design and aim with those now employed. The method of the Egyptians of plastering on reeds closely resembles our use of lath. The tools of today were used in Egypt 3000 years ago and in Pompeii in the day of Julius Caesar. The technique of Greece and Brittany, of Rome and Gaul was the same. The material of the classic workers at Athens 800 years before Christ
differs in no particular from that in use at the present.
Archeologists reveal that stucco of various kinds, natural and in color, was known in very ancient days for covering of walls. As long as five centuries before Christ its use had advanced to a high artistic standard when it covered temples both outside and in, even in cases where the building was of marble. There it formed a fine foundation for decorative painting which at this period of Greek history had reached a high degree of beauty. The extent of its use was very wide. In early times it was not un
PLASTER CEILING IN DIRECTORS’ ROOM IN BUILDING OF TRAVELERS INSURANCE CO., HARTFORD. CONN.
DONN BARBER, ARCHITECT
Mortar for plaster work is usually composed of slaked lime mixed with sand and hair. The sand should be hard, sharp, gritty and free from all organic matter. Hair is used as a binder to increase cohesion and tenacity. For this purpose it should be long, strong, and free from grease or
other impurities. Ox hair is generally used, although sometimes adulterated with the short hair of horses. Substitutes for hair include manila fiber and sawdust.
Plaster of Paris is obtained from gypsum by gentle calcination. It is very soluble in water, and this fact renders it unfit for external use. It is, however, valuable for decorative details, for cornice, molds, and other enrichments, and is also used in several plastic mixtures. Plaster of Paris sets rapidly, acquiring full strength in a few hours.
Research has disclosed the fact that in essential
particulars the tools of plasterers in the early history of the craft were identical in design and aim with those now employed. The method of the Egyptians of plastering on reeds closely resembles our use of lath. The tools of today were used in Egypt 3000 years ago and in Pompeii in the day of Julius Caesar. The technique of Greece and Brittany, of Rome and Gaul was the same. The material of the classic workers at Athens 800 years before Christ
differs in no particular from that in use at the present.
Archeologists reveal that stucco of various kinds, natural and in color, was known in very ancient days for covering of walls. As long as five centuries before Christ its use had advanced to a high artistic standard when it covered temples both outside and in, even in cases where the building was of marble. There it formed a fine foundation for decorative painting which at this period of Greek history had reached a high degree of beauty. The extent of its use was very wide. In early times it was not un
PLASTER CEILING IN DIRECTORS’ ROOM IN BUILDING OF TRAVELERS INSURANCE CO., HARTFORD. CONN.
DONN BARBER, ARCHITECT