Russia
gauge
number.
Birmingham
wire-gauge
number.
Thickness
in decimal
parts of
an inch.
729 .013
828 .014
927 .016
1026 .018
1125 .020
122412.021
1324 .022
142314——
152238——
162112——

The following table gives the gauge numbers to which galvanized iron is made.[26]

[26] Galvanized iron is made to the Birmingham wire-gauge, the thickness includes the galvanizing, the sheets being rolled thinner to allow for it.

Gauge
number.
Thickness.Gauge
number.
Thickness.
Inch. Inch.
14.08323.025
16.06524.022
17.05825.02
18.04926.018
19.04227.016
20.03528.014
21.03229.013
22.028

In the following table is given the American gauge sizes and their respective thicknesses for sheet zinc.

Gauge and Thickness.Gauge and Thickness.
Number.Approximate
Birmingham
wire-gauge.
Thickness in
fractions of
an inch.
Number.Approximate
Birmingham
wire-gauge.
Thickness in
fractions of
an inch.
1——0.003916——0.0447
5——0.011317——0.0521
6——0.013218——0.0596
7——0.015019——0.0670
8280.016920——0.0744
9270.018721——0.0818
10260.022422——0.0892
11250.026123——0.0966
12240.029824——0.1040
13——0.033625——0.1114
14——0.037326——0.1189
15——0.0410

The Belgian sheet zinc gauge is as follows:

Gauge
number.
Thickness in
decimal parts
of an inch.
Gauge
number.
Thickness in
decimal parts
of an inch.
1.00414.037
2.00615.041
3.00816.045
4.00917.052
5.01118.059
6.01319.067
7.01520.074
8.01721.082
9.01922.089
10.02223.097
11.02624.104
12.03025.111
13.03426.120

The gauge sizes of the bores of rifles are given in the following table,[27] in which the first column gives the proper gauge diameter of bore, and the second the actual diameter containing the errors found to exist from errors of workmanship. The standard diameters are supposed to be based upon the number of spherical bullets to the pound weight, if of the same diameter as the respective gauge sizes.

[27] From The English Mechanic.