I found some new quotes that demonstrate the importance of engineering handbooks:
"Handbooks, encyclopedias, and dictionaries are an integral part of the engineer's library." pg. 5
"Handbooks provide fast access to charts, tables, short descriptions, formulas, and so on needed to do everyday tasks. While most engineers will have a copy of the handbooks that are most relevant to their work on their desk or on their computer desktop, they will seldom have access to the wide range of handbooks to support the increasingly interdisciplinary nature of engineering." pg. 5
The word "handbook" appears on 180 of 548 pages.
Osif, B.A. (2006). Introduction. In B.A. Ossif (Ed.) Using the engineering library. Routledge studies in library and information science, 1. (pp. 1-8)London: Routledge.