I've put together Dueber-Hampden adverisements from about 1890-1911. They are courtesy of Google Books.

Historical collections of Ohio Volume 2

January, 1890 Brotherhood of Locomotive Engineers Monthly Journal, Volume 24

January 1891 Journal of the Brotherhood of Locomotive Engineers, Volume 25 Number 1

February, 1897 Jewelers' Circular, Volume 34

April, 1899 The Jewelers Review, Volume 32

April, 1899 The Jewelers Review, Volume 32.

December, 1899 Harper's Magazine, Volume 100

January, 1900 The Jewelers' Circular and Horological Review, Volume 39

January, 1900 The Railroad Trainman, Volume 17

June, 1900 The Railway Conductor, Volume 17.

June, 1900 The Railway Conductor, Volume 17

October, 1900 Brotherhood of Locomotive Fireman and Enginemen, Volume 29

November, 1900 Scribner's Magazine, Volume 28

May, 1900 The Century Illustrated Monthly Magazine, Volume 38

May, 1900 The Cosmopolitan, Volume 29 Number 1

Here are some prices.

January, 1901 The Free Thought Magazine, Volume 19

May, 1901 Frank Leslie's Popular Monthly, Volume 52 pg.27

May, 1901 Frank Leslie's Popular Monthly, Volume 52

July, 1901 Scribner's Magazine, Volume 30

November, 1901 McClure's Magazine, Volume 18

January, 1902 The American monthly Review of Reviews, Volume 25

September, 1902 The Delineator, Volumes 101-102

October, 1902 Munsey's Magazine, Volume 28

March, 1902 Scribner's Magazine

June, 1903 New Pearson's Magazine, Volume 10

January, 1905 The American Federationist, Volume 12 Number 1

January, 1910 The Railroad Telegrapher, Volume 27 Number 1.

January, 1910 The Railroad Telegrapher, Volume 27 Number 1

July, 1910 The Railroad Telegrapher, Volume 27 Number 7

January, 1911 Locomotive Engineers Journal, Volume 45 Number 1

Almost forgot this one.
January, 1904 Everybody's Magazine, Volume 10

Here's the link to Dueber-Hampden Trademarks.

United States Horological Trademark Index

RR

Nice work, Richard! I love the ad with the Father Time figure. Nice jab at Elgin. Some of these are ads I haven't seen before.