The experiment descriptions given in this manual would not have been possible without financial support from many sources. The instruments used for the nuclear physics experiments were purchased with faculty start-up funds provided by the office of Prof. Robert Gleason, then the Dean of the Faculty at Middlebury College. Most of the major instruments in our laser spectroscopy laboratory were purchased with funds provided by Grant CSI-8551496 of the National Science Foundation's College Science Instrumentation Program (CSIP). The telescopes used in the solar spectroscopy experiments were purchased with funds provided by Grant CSI-875046 of the CSIP. These CSIP grants were generously matched by funds provided by Middlebury College. The Keck Foundation provided support for the purchase of the argon ion and ring dye laser systems. The New England Consortium for Undergraduate Science Education (NECUSE) sponsored by the Pew Charitable Trusts has generously provided funds in direct support of many of the laboratory experiments described here. Throughout our laboratories we have benefitted from instruments donated to us through the IBM Technical Gifts Program.

Any innovation that might be found in this manual can most likely be traced to the senior thesis work of former students. Among these students, I would especially like to thank Eric Anthony, James Appleby, John Bassi, Rich Belanger, Otto Berkes, Ken Davis, Tom Donnelly, Tim Ferris, Dean Jordan, Mike Kaufman, Chris Summersgill, Rob Tucker, Debbie Vehse, and John Weiss for their enthusiasm and their lasting contributions to our sophomore laboratory program. Every member of the physics department faculty has contributed in some way to these experiments and I thank them all for their genuine interest and support. I especially thank Stephen Ratcliff who provided the inspiration for and texts of Expts. XV and XVI. The entire package of twenty experiments would not have come together - and worked - without the expert assistance and cheerful encouragement of Cris Butler, our laboratory supervisor.

Although due credit must be given to Stephen Ratcliff for the photographs of Expt. XVI, the bulk of the photography in this manual must be credited to Erik Borg, who has demonstrated his interest in our laboratory development efforts by documenting our progress in the beautiful photographs included in this manual. Kathleen Tellier supervised the production of this manual and is to be thanked for her dedication and good humor.

This is the second time we have put our modern physics laboratory experiments together in a manual. Eight new experiments have been added to the manual, and no doubt, a few new errors have crept in as well. I would appreciate receiving any corrections or suggestions from students who struggle through these experiments.

Jeff Dunham

September 11, 1991