124 ANNUAL REPORT 
CHAPTER IV. 
THE USES OF CEMENT IN REINFORCED CONCRETE. 
“Reinforced concrete,’ “Armored concrete,’ or “Steel concrete’ as 
it is variously called, is the structure resulting from the use of concrete 
with iron or steel ribs or “bones” running through the concrete mass. 
EARLY USE OF REINFORCED CONCRETE. 
Condensed extracts from a discussion upon Steel Concrete Construc- 
tion by, Mr Ay Icy Johnson, “Assoc: Ma Am Seer @) printed inathe 
Proceedings of the American Society of Civil Engineers, follows. He 
gives to Mr. W. E. Ward the credit of having first used steel reinforced 
concrete in a scientific manner in a building which he erected in Port 
Chester, N. Y., in 1875. Mr. Ward constructed a building in which “not 
only all the external and internal walls, cornices and towers were con- 
structed of beton (the word concrete was not then in use), but all the beams 
and roofs were exclusively made of beton reinforced with light-iron beams 
and rods.” 
“Francois Coignet of Paris, in 1869, took out patents on a combina- 
tion of beton and iron rods, but he had no conception of the proper method 
of using the materials.” 
Monier built his first wire and beton flower pots in 1876, but the 
manner in which he combined the two materials showed that he did not 
understand the principles of reinforced concrete. He placed the wire 
webbing in the neutral axis of the slab; while it answered his purpose, 
it would be disastrous to attempt such construction upon beams or in 
bridges. . 
Thaddeus Hyatt, of England, began experiments upon reinforced 
concrete in 1876, the result of which he published in 1877. 
It is probable that the first approximately correct formulas for re- 
inforced concrete were derived by Julius Mandl in Germany, and Prof. J. 
B. Johnson in this country at about the same time. 
_ L. A. Saunders, engineer for Monier construction, in Germany, pub- 
lished an extensive treatise upon the subject. In 1899 M. Considere, 
Ingenieur en Chef des Ponts et Chaussees. Paris, published a long dis- 
cussion upon Ciment-arme. ‘His studies embraced the following points: 
i 
