Skip to main content

Kenneth J. Germeshausen, Notebook 1, [October 15, 1931, to January 14, 1932], 1931 - 1932

 File — Box: 50, Folder: 5
Identifier: cuid21433

Series Description

From the Series:

Harold Edgerton's laboratory notebooks (Series 3A) are a central source of information for his research activities from 1930 to 1990 as well as many other personal and professional activities. Researchers interested in what Harold Edgerton was doing at a particular time should look first in the chronologically-maintained notebooks. Notebook entries reveal names of projects in progress, equipment used, and people involved. Researchers may then consult names listed under subject correspondence (Series 2), research projects (Series 3), and technical specifications and plans (Series 3) in the finding aid to the Harold Edgerton papers in the Institute Archives (collection MC 25) to attempt to locate additional information pertaining to those projects, equipment, or people. Also, Edgerton often published his research findings within months after obtaining results in the laboratory. Researchers should look at articles with appropriate dates in the list of writings (Series 7).

Laboratory notebooks (box 50 - box 57, box 162) illustrate through notes, diagrams, data, and photographs the step-by-step evolution of Edgerton's innovative ideas from inspiration to finished plan or product. The notebook entries reveal the excitement generated among his colleagues at MIT by his early demonstrations of stroboscopic phenomena and show how techniques developed by him to discover ways of improving industrial efficiency found useful applications in other areas. Edgerton's habit of calling in colleagues from neighboring labs to sign notebook pages reveals his awareness of the potential economic value of his research. Of special interest is the fact that he recorded personal diary entries regarding births, marriages, visits by friends, and recreation in his laboratory notebooks, sandwiched between entries containing complicated calculations and diagrams. The notebooks are a consistent record of Harold Edgerton's research activities in his MIT lab from 1930 to 1990, with entries made every day or every few days during the school year and less frequently during summers. The notebooks are supplemented by sonar records (box 58, folder 1 - box 59, folder 5, and boxes 131-134) and by notebooks in trips files (see Series 6, box 90, folder 7 - box 104, folder 7), which further illuminate specific research efforts. The notebooks contain references indicating that he maintained other notebooks. Summaries by Edgerton of notebooks earlier than 1930 are found on pages 72-73 of Notebook T-2 (box 50).

An alternative research strategy would be to scan the list of writings (Series 7) by Harold Edgerton to find topics of interest among the titles. Dates of publication often followed laboratory results by several months. The researcher should note dates of articles and then consult the laboratory notebook entries (Series 3) immediately preceding the published work. These entries should contain names that will enable the researcher to continue as outlined above.

Harold Edgerton's innovations and improvements to equipment such as flash devices and systems for underwater mapping and photography are described not only in the laboratory notebooks (box 50 - box 57), but also in technical specifications and plans (box 59, folder 6 - box 73, folder 10). These files contain diagrams, photographs, and technical information about a wide range of research projects, including beacons (box 59, folder 14 - box 60, folder 2), boomers (for location of underwater objects) (box 60, folders 9-14), cameras (box 60, folder 18 - box 61, folder 2), elapsed time movie equipment (box 62, folders 1-4), flash units (box 62, folder 5 - box 63, folder 2), pingers [for positioning underwater cameras] (box 66, folder 13), piddlers [for demonstrating stroboscopic effects] (box 66, folder 12), sonar systems (box 68, folders 10-11), stroboscopes (box 69, folder 7 - box 70, folder 2, and box 135), and other devices. These files generally contain finished plans for purposes of reference and do not show the evolution of ideas as clearly as the notebook entries.

Annotated site maps (boxes 131-133) and sonar charts (box 58, folder 1 - box 59, folder 5, and box 134) in the series document Harold Edgerton's research using sonar equipment to search for underwater objects, such as shipwrecks and architectural ruins, between 1955 and 1986.

Research projects files (box 73, folder 11 - box 83, folder 4, and boxes 136-137) include documentation of Edgerton's work in designing and testing powerful flash units for use on Allied reconnaissance planes in World War II. The D-5 flash unit and related equipment developed by Edgerton, used to photograph enemy troop movements after dark, contributed significantly to the success of the Normandy invasion and other Allied victories. Material includes correspondence, blueprints, and reports (box 77, folder 1 - box 81, folder 7), as well as two photograph albums (boxes 136-137) and a video recording (box 171).

Harold Edgerton's interest in and contributions to other projects are also documented in the research projects section. These files contain audiotapes (boxes 139, 142, 143), videotapes (boxes 170-175), background material, and correspondence created or compiled by him (box 73, folder 11 - box 83, folder 4), relating to topics that intrigued him. Much of this material is complementary to information in the trips series. Information about his earlier research efforts can also be found in the writings and speeches series (box 104, folder 8 - box 116, folder 17, and boxes 141, 143) and in a related collection in the MIT Archives, MC 132, Harold Eugene Edgerton, Oral History, 1975.


  • 1931 - 1932

Access note

Materials in this collection are open unless they are marked as restricted. Restrictions are noted in the container list.


From the Collection: 132096 Megabytes (129 GB (138,996,944,896 bytes) on disk) : TIF files from microfilm digitization

From the Collection: 2143 Megabytes (multiple files)

From the Collection: 6656 Megabytes (6.5 GB in 39 Files, 15 Folders)

From the Collection: 52 Cubic Feet (1 record carton, 133 manuscript boxes 8 half manuscript boxes, 5 tubes, 2 pamphlet boxes, 1 half pamphlet box, 3 flat boxes, 3 cassette boxes, 1 CD box, 36 microfilm reels in 6 microfilm boxes, 9 photograph albums and 5 scrapbooks each in enclosure, 6.5 GB in 39 Files, 15 Folders [one folder per original audio tape], 129 GB of digitized microfilm of laboratory notebooks)

Language of Materials



Repository Details

Part of the Massachusetts Institute of Technology. Libraries. Department of Distinctive Collections Repository

Massachusetts Institute of Technology Libraries
Building 14N-118
77 Massachusetts Avenue
Cambridge MA 02139-4307 US