Skip to main content

Samuel Ottmar Mast papers

Identifier: MS-0135

  • Staff Only
  • No requestable containers

Scope and Contents

The collection consists of three series: correspondence, Johns Hopkins University material, and printed material with material ranging in date from 1912 to 1947. The correspondence forms the largest series, and is divided into incoming (arranged alphabetically) and outgoing (arranged chronologically). The letters fully describe Mast's research and his administrative duties.

Mast's colleagues and former students sought his comments on their work. He responded in detail, criticizing both experimental methods and results. Genetics, physiology, and behavior of unicellular organisms were the primary fields for research in the zoological division of the Biology department, and his correspondence touches on developments in each of these areas.

Letters from 1931-1932 and 1936 on describe the frustrations of running an academic department during the Depression. In addition to searching for money for graduate students, Mast had to help place recent Ph.D.'s in a flat market. His outgoing letters detail his attempts to keep the department and his students on stable financial ground.

The Johns Hopkins University material consists of charts of faculty and students. These were probably prepared by Mast in support of the New Plan for undergraduates favored first by President Frank Goodnow and later Isaiah Bowman. This scheme would eliminate the first two years of college instruction, and make Hopkins an institution solely for upper-level undergraduates and graduate students. The New Plan was never implemented.

Two reprints sent to Mast form the printed material series. They are: Sentis, M. H., Tension Superficielle de l'Eau et des Solutions Salines; and, Wetham, W. C. D. The Ionization of Dilute Solutions at the Freezing Point.


  • Creation: 1912-1947


Conditions Governing Access

This collection is housed off-site and requires 48-hours' notice for retrieval. Contact Special Collections for more information.

This collection is open for use.

Conditions Governing Use

Single copies may be made for research purposes. Researchers are responsible for determining any copyright questions. It is not necessary to seek our permission as the owner of the physical work to publish or otherwise use public domain materials that we have made available for use, unless Johns Hopkins University holds the copyright.

Biographical Note

Samuel Ottmar Mast was born on October 5, 1871 near Ann Arbor, Michigan. He received his B. S. from the University of Michigan in 1899 and completed his Ph.D. at Harvard in 1906. Mast taught at Hope College in Howland, Michigan from 1899-1908. His longest academic association, however, was with Johns Hopkins University.

In 1907-1908, Mast held a fellowship from Hopkins as a Johnston researcher. After its termination, Mast joined the botany department at Goucher College, then rejoined the Hopkins Zoology Department as associate professor in 1911. He was promoted to full professor in 1917, a rank he held until his retirement in 1941.

Mast's tenure at Hopkins included administrative duties. In 1938 Jennings, longtime head of the Department of Zoology, left Hopkins for UCLA. Mast succeeded Jennings as head and Director of the Zoological Labs. He had previously served as acting head when Jennings was a visiting professor in Japan (1931-1932) and at Oxford (1936-1937).

On August 26, 1908, Mast married Grace Rebecca Tennent. They had three daughters: Louise Rebecca Specht, Elisabeth Tennent Buck, and Margaret Tennent Rhodes. Samuel Ottmar Mast died on February 3, 1947. He was survived by his wife, Grace Tennent Mast, and their three daughters.


4.7 Cubic Feet (10 legal size document boxes)

Language of Materials



Samuel Ottmar Mast (1871-1947) was a biologist and zoologist at Johns Hopkins University. The collection consists of correspondence, administrative information related to running an academic department, and reprints of articles. The collection materials range in date from 1912 to 1947.

Immediate Source of Acquisition

The papers were probably transferred to the Library sometime after Mast's death in 1947.


Additional information about the Johns Hopkins biology department during this period may be found in an unpublished typescript by R. Parker Cowles, "History of the Johns Hopkins University Biology Department." The typescript is in the University Archives.

Processing Information

Finding aid prepared by Margaret N. Burri in 1988.

Rachel Gattermeyer revised the scope and contents note in this finding aid in December 2023 to bring it into compliance with Johns Hopkins guidelines for inclusive and conscientious description (2023). The previous version of the finding aid is available upon request.


Guide to the Samuel Ottmar Mast papers
Description rules
Describing Archives: A Content Standard
Language of description
Script of description
Language of description note

Repository Details

Part of the Special Collections Repository

The Sheridan Libraries
Special Collections
3400 N Charles St
Baltimore MD 21218 USA