John Abner Bagley, 1835 - 1896

by Brian Stevenson
last updated March, 2026

John A. Bagley, of New York City, was a microscope enthusiast during the 1880s. He was particularly interested in diatoms, and prepared a number of good quality slides of such specimens. He was a member of the American Society of Microscopists and the New York Microscopical Society.

Figure 1. Microscope slides of diatom strews from a variety of locations, prepared ca. 1880s by John A. Bagley. The slide on the right has “Camp Pond” and “Cover 1/130" ” diamond-etched into the glass. The location may have been Camp’s Pond, a natural kettlehole pond on the South Fork of Long Island, NY, near the town of Water Mill.

Figure 2. Mix of diatoms from Camp Pond, prepared ca. 1885 by John A. Bagley (see Figure 1). Imaged with a 10x objective lens and C-mounted digital SLR camera on a Leitz Ortholux II microscope.

Figure 3. John Bagley owned high-end microscope equipment, including at least four Tolles objective lenses. He advertised to sell them 1886. He resigned from the New York Microscopical Society in 1887, so these sales probably indicate his declining interest in hobby microscopy. From “The American Monthly Microscopical Journal”.

John Abner Bagley was born on September 10, 1835, the first child of John S. and Margaret (aka Martha) Harper Bagley. The father was described in census records as being a “commercial merchant”. Those records also note multiple live-in servants, implying a fairly wealthy household. While in his teens, John lived with his grandfather, Abner Bagley, in Newburyport, Massachusetts.

Our microscopist enrolled in the Rensselaer Polytechnic Institute in the autumn of 1850, and graduated as a civil engineer in 1853. After working for a year in North Carolina, Bagley moved back to New York City to work as a surveyor for the city. He remained a city surveyor for the remainder of his life.

In the mid-1860s, Bagley bought the house at 45 East 28th Street, in New York. Censuses show that he enjoyed the comforts of live-in servants. He married Katherine C. Corey on March 13th, 1877. They do not appear to have had any children.

College alumni publications note that Bagley “wrote articles on engineering subjects for Appleton's New American Cyclopedia” in 1858.

Bagley joined the American Society of Microscopists in 1883. He likely joined the New York Microscopical Society around the same time. As noted above in Figure 3, he acquired high-quality, expensive microscope equipment to pursue this hobby.

Bagley’s known microscope slides and his entries in The Naturalists' Universal Directory indicate especial interest in diatomaceae. The only published description of Bagley’s slides that I located was in an 1885 issue of The Journal of the New York Microscopical Society, where “Navicula sillimanorum, from Crane Pond, Mass.; mounted by Mr. J.A. Bagley” was exhibited on May 1, 1885.

His advertisements to sell Tolles objective lenses were published in 1886. Bagley formally resigned from the New York Microscopical Society in 1887. He was still listed as a member of the American Society of Microscopists in 1888, but had ceased membership by 1891.

John Bagley died of “apoplexy” (stroke) on January 11, 1896.

Figure 4. Hyalodiscus subtilis and other diatoms from California (see Figure 1). Imaged with a 10x objective lens and C-mounted digital SLR camera on a Leitz Ortholux II microscope.

Figure 5. Diatoms from Santa Monica, California – The Original Find”, prepared ca. 1885 by J.A. Bagley (see Figure 1). Imaged with a 10x objective lens and C-mounted digital SLR camera on a Leitz Ortholux II microscope.

Resources

The American Monthly Microscopical Journal (1886) Advertisements from John A. Bagley, multiple issues

Biographical Record of the Officers and Graduates of the Rensselaer Polytechnic Institute, 1824-1886 (1886) John A. Bagley, page 286

Documents of the Assembly of the State of New York (1860) Records of bills due to John A. Bagley for surveying, pages 92-93

Engineering News (1896) “Mr. John A. Bagley, civil engineer, of New York city, died of apoplexy Jan. 11, at the age of 62”, page 21

Journal of the New York Microscopical Society (1885) Minutes of the meeting of May 1, page 155

Journal of the New York Microscopical Society (1887) “The resignation of Active Membership by Mr. John A. Bagley … was accepted”, page 6

The Naturalists' Universal Directory (1888) "Bagley, John A., C.E., 45 East 28th St., New York, N.Y. Mic. Diatoms *”, Cassino, Boston, page 7 (note: the asterisk indicates that the publisher had not heard from Bagley for several years)

The Polytechnic (1896) “John A. Bagley died in New York city January 11. Mr. Bagley had been a civil engineer in the metropolis for years. He was born in New York city September 10, 1833. He was a member of the New York Microscopical Society, and wrote articles on engineering subjects for Appleton's New American Cyclopaedia”, pages 90 and 128

Proceedings of the American Society of Microscopists (1884) Election of new members, page 263

Trow’s New York City Directory (1872) “Bagley John A. surveyor, h 43E. 28th”, page 54

Trow’s New York City Directory (1886) “Bagley John A. city surveyor, h 43E. 28th”, page 74

US census and other records, accessed through ancestry.com