Abstract :
The following article is an “Introduction” to a discussion to take place at a meeting of the Institute in the Auditorium of the Engineers´ Building, 33 West Thirty-ninth Street, New York, Friday, March 22, 1907, at 8 p.m. It is not intended to be a formal or complete paper, but to serve merely as a basis or framework for discussion on the subject with which it deals. All those connected with the Institute and desiring to take part in this discussion may do so by being present at the meeting, or if this is not possible by sending in a written “Contribution.”
