"1. The entire process of manufacture shall be in accordance with the best current state of the art.
"(a) Ingots shall be kept in a vertical position until ready to be rolled, or until the metal in the interior has had time to solidify.
"(b) Bled ingots shall not be used.
Chemical composition.
"2. The chemical composition of the steel from which the rails are rolled shall be within the following limits:
| Bessemer. | Open-Hearth. | |||
| 70 lbs. and over, but under 85 lbs. | 85 to 100 lbs. inclusive. | 70 lbs. and over, but under 85 lbs. | 85 to 100 lbs. inclusive. | |
| Carbon | 0.40 to 0.50 | 0.45 to 0.55 | 0.53 to 0.66 | 0.63 to 0.76 |
| Manganese | 0.80 to 1.10 | 0.80 to 1.10 | 0.70 to 1.00 | 0.70 to 1.00 |
| Silicon | 0.07 to 0.20 | 0.07 to 0.20 | 0.07 to 0.20 | 0.07 to 0.20 |
| Phosphorus, not to exceed | 0.10 | 0.10 | 0.04 | 0.04 |
| Sulphur, not to exceed | 0.075 | 0.075 | 0.06 | 0.06 |
"3. When the average phosphorus content of the ingot metal used in the Bessemer Process at any mill is below 0.08 and in the Open-Hearth Process is below 0.03, the carbon shall be increased at the rate of 0.035 for each 0.01 that the phosphorus content of the ingot metal used averages below 0.08 for Bessemer steel, or 0.03 for Open-Hearth steel.
"The percentage of carbon in an entire order of rails shall average as high as the mean percentage between the upper and lower limits.
Shearing.
"4. The end of the bloom formed from the top of the ingot shall be sheared until the entire face shows sound metal.