Recent developments in light signal for control of highspeed traffic

• Publisher: Elsevier Science
• Year: 1915
• Tongue: English
• Weight: 67 KB
• Volume: 180
• Category: Article
• ISSN: 0016-0032
• DOI: 10.1016/s0016-0032(15)90570-7

✦ Synopsis

CURRENT TOPICS. 637 ipated for them in the building of safes. Not only are the plates so extremely hard that they cannot be drilled, but they have a remarkable resistance to the flame of an oxyacetylene lamp. It is estimated that to burn a hole three inches in diameter and 3~ inch thick would require six hours and the consmnption of 350 cubic feet of oxygen and 320 cubic feet of acetylene.