rollings are covered by patents and necessitate royal- 

 ties, which increase the cost of the steel from $2 up 

 per ton. 



A plain square bar twisted is generally accepted 

 as furnishing a mechanical bond. This can be either 

 what is known as cold-twisted or hot-twisted. To re- 

 duce this discussion to what the user of this handbook 

 will in most cases receive on the work, we find that 

 there are in most general use four types of steel: 

 A. Plain square or round mild Open Hearth. 

 B. Plain square or round Rerolled Bessemer. 

 C Twisted square (A) "Cold Twisted." 

 D. Twisted square (B) "Hot Twisted." 

 Relative to "rerolled," this is a term applied to bars 

 rerolled from the heads of railroad rails which are 

 out of service. The rails are bought by the rerolling 

 mills at a very low ton price, and are reheated, split, 

 and the different parts rolled into shapes such as angles 

 or flats. The heads are generally used for reinforcing 

 bars. 



It is perhaps pertinent to introduce at this point a 

 ion of the market cost of steel. This of course 

 varies with trade conditions, but today the price on 

 Open Hearth steel (A and material of C) is $1.40 

 per carload lots, base F. O. B. Pittsburg. By "base" 

 is meant all sizes from )4-in. to 3-in. inclusive. The 

 schedule in the table, "Differential for Size," shows the 

 regular association extras, for sizes below ^4 in- 

 Cold twisting increases the cost of this material from 

 loc per cwt. ($2 per ton) or more, depending upon 

 conditions. 



The price on rerolled plain material is $1.30 per cwt., 

 carload lots, base, Pittsburg. Hot twisted carries a 

 loc increase, making it cost $1.40 carload lots, base, 

 Pittsburg. These prices are for the season of 1908, 

 and are of course subject to change. 



