Collaboration
ART
BEAUTY & WELLNESS
CRAFT
CULTURE & HISTORY
ENTERTAINMENT
ENVIRONMENT
FOOD & DRINKS
REVERSE ENGINEERING
SCIENCES
SPORTS
TECHNOLOGY
WEARABLES
Air Thermometer: Blackened Tin Box and Water U-Tube (Boy Mechanic, 1913)
The Boy Mechanic, Book 1 (1913), p. 153, public domain · Public domain
Penny

Created by

Penny

14. November 2026DK
0
0
0
0
0

Air Thermometer: Blackened Tin Box and Water U-Tube (Boy Mechanic, 1913)

A sensitive air thermometer: a small sealed tin box, blackened on its face, breathes through a brass tube into a bent glass U-tube holding a little water; warmth on the box expands the air and pushes the water up the scale.
Intermediate
Two hours

Instructions

1

Read the Boy Mechanic

"This instrument will measure the amount of heat given by a candle some 20 or 30 ft. away."
2

Seal the box

Take a small tin box about 1-1/4 in deep and 2 in across. Solder a 1 in piece of 1/4 in brass tube into its side, then solder the cover on so air can only escape through the tube.

Materials for this step:

Tin CanTin Can1 piece
Brass TubeBrass Tube1 piece
Tin-Lead SolderTin-Lead Solder1 piece

Tools needed:

Soldering IronSoldering Iron
Hand DrillHand Drill
3

Bend the glass tube

Take 1/4 in glass tube at least 18 in long and bend it into a U as in the figure by holding it across a broad flame until it sags under its own weight. Join it to the brass tube with a short rubber hose, bound with fine copper wire if loose.

Materials for this step:

Glass TubeGlass Tube1 piece
Rubber TubingRubber Tubing1 piece
Copper WireCopper Wire1 piece

Tools needed:

Alcohol Burner (Spirit Lamp)Alcohol Burner (Spirit Lamp)
4

Stand and base

Make the standard from No. 10 wire about 10 in long on an oak base, with a No. 14 wire soldered across it and bent round the brass tube and the glass tube.

Materials for this step:

Iron WireIron Wire1 piece
White Oak BoardWhite Oak Board1 piece
Tin-Lead SolderTin-Lead Solder1 piece

Tools needed:

Flat-Nose PliersFlat-Nose Pliers
Soldering IronSoldering Iron
Brace and BitBrace and Bit
5

Blacken and fill

Smoke the bottom of the box black over a little burning cotton soaked in turpentine (after any painting of the rest). Put water in the U-tube with a dropper and paint a scale on the glass.

Materials for this step:

LampblackLampblack1 piece
Black PaintBlack Paint1 piece
Distilled WaterDistilled Water1 piece
6

Troubleshooting

Air thermometer troubleshooting.

Flow

Loading...
7

History and honest limits

From **The Boy Mechanic, Book 1** (Popular Mechanics, 1913), pp. 152-153, by J. Thos. Rhamstine (checked on the archive.org scan boymechanic0000unse_n5a8). It shows relative warmth, not degrees. He also mentions etching the scale with hydrofluoric acid; we use paint only. The spirit lamp in place of a gas jet is ours.

Materials

11

Tools Required

5

This blueprint makes

Thumbnail
Placeholder

Thermometer

Free

1,324
0

Related Blueprints

These blueprints share knowledge with this one — techniques, materials, or principles that connect them in the learning graph.

Silk-Thread Hygrometer with a Magnifying Sag and Pointer (Boy Mechanic, 1913)

Silk-Thread Hygrometer with a Magnifying Sag and Pointer (Boy Mechanic, 1913)

by PennyDK

Physics

0
0
0
0
0
0

CC0 Public Domain

This blueprint is released under CC0. You are free to copy, modify, distribute, and use this work for any purpose, without asking permission.

Support the Maker by purchasing products through their Blueprint where they earn a Maker Commission set by Vendors, or create a new iteration of this Blueprint and include it as a connection in your own Blueprint to share revenue.

Discussion

(0)

Log in to join the discussion

Loading comments...