Bartlett Poppet Valve Gear, Patent Model

This model was submitted to the U.S. Patent Office with the application for the patent issued to Louis D. Bartlett, of Fitchburg, Massachusetts, January 15, 1867, no. 61141.
The patent refers to an engine with separate valve chests at head end and crank end, each enclosing balanced steam and exhaust poppet valves, and describes particularly the construction of the valve boxes. These are designed for simplicity of casting, machining, and accessibility but are difficult to describe without reference to the drawings in the patent specifications. The valve gear is said to be similar to one described in a patent granted to Charles H. Brown and Charles Burleigh, January 15, 1856. The valve stems are operated by short levers, which are raised and lowered by cams on a lay shaft paralleling the cylinder. The levers that operated the steam valves have variable fulcrums, which are controlled by a governor so that the steam can be cut off at any point of the stroke.
This description comes from the 1939 Catalog of the Mechanical Collections of the Division of Engineering United States Museum Bulletin 173 by Frank A. Taylor.
Currently not on view
Object Name
valve, steam engine, model
patent model, valve, steam engine
date made
patent date
Bartlett, Louis D.
Physical Description
wood (overall material)
overall: 5 in x 12 5/8 in x 8 3/8 in; 12.7 cm x 32.0675 cm x 21.2725 cm
on base - from catalog card: 8 1/2 in x 11 in; 21.59 cm x 27.94 cm
place made
United States: Massachusetts
associated place
United States: Massachusetts, Fitchburg
ID Number
catalog number
accession number
patent number
Engineering, Building, and Architecture
Industry & Manufacturing
Bulletin 173
See more items in
Work and Industry: Mechanical and Civil Engineering
Bulletin 173
Data Source
National Museum of American History, Kenneth E. Behring Center
Related Publication
Frank A. Taylor. Catalog of the Mechanical Collections of the Division of Engineering United States National Museum, Bulletin 173

Visitor Comments

Add a comment about this object

**Please read before submitting the form**

Have a comment or question about this object to share with the community? Please use the form below. Selected comments will appear on this page and may receive a museum response (but we can't promise). Please note that we generally cannot answer questions about the history, rarity, or value of your personal artifacts.

Have a question about anything else, or would you prefer a personal response? Please visit our FAQ or contact page.

Personal information will not be shared or result in unsolicited e-mail. See our privacy policy.

Enter the characters shown in the image.