In conclusion, the writers cannot forego the pleasure of expressing
their deep obligation to Samuel Rea, M. Am. Soc. C. E., as representing
the Management of the Company, to the Chief Engineer, Charles M. Jacobs,
M. Am. Soc. C. E., and to James Forgie, M. Am. Soc. C. E., Chief
Assistant Engineer, for their permission to write this paper, and also
to all the members of the field office staff for their great and
unfailing assistance in its preparation.