336 



THE APPLICATIONS OF PHYSICAL FORCES. [BOOK iv. 



But we have no intention of tracing here the history of the art of 

 warming, nor of inquiring whether the ancient Greeks or Romans were 

 acquainted with chimneys, or if, on the contrary, these useful appli- 

 ances only made their appearance during the Middle Ages in the 

 houses of Western Europe. That improvements which in these days 

 appear so simple should have been so slowly introduced is nothing- 

 extraordinary when we consider that our present civilisation has 

 advanced from the South and the East towards the West and the 

 North. The Greeks used to pass a great part of their life in the 

 open air, and the mild climate of the Islands of the Archipelago 



FIG. 230.- Warming among the ancients. Grecian tripods. 



and of the Peninsula of Greece did not render necessary any excep- 

 tional precautions against the cold of winter. They were satisfied to 

 moderate the temperature of their houses by placing braziers upon 

 tripod-stands with lighted coals beneath the warm ashes a method of 

 warming which was neither very efficacious nor very healthy. The 

 tripods of the Greeks and the foculi of the Romans are still found 

 under the name of brascros in southern countries, as in Greece, 

 Italy, and in Spain. 



We come then to the appliances for warming made use of in 

 modern times, and we will begin with fireplaces. 



