Page [199] “acetylcholine esterase.” - had “acetylcholin”.

Page [200] “George de Hevesy, Carl F. Cori,” - comma added after Hevesy.

Footnote [39]: “See, e.g., Chemical Week, vol. 77” - had “See. e.g.”

The spelling of “Bertholet” [Claude Louis Berthollet] is as given on the original title page of the work referenced in this paper.

Inconsistent hyphenation of chemical names has been retained.

Contributions from
The Museum of History and Technology.
Paper 41
Tunnel Engineering—A Museum Treatment

Robert M. Vogel

[INTRODUCTION]203
[ROCK TUNNELING]206
[SOFT-GROUND TUNNELING]215
[BIBLIOGRAPHY]239
[FOOTNOTES]
[INDEX]