Comparison of the Numbers of the Standard Decimal Gauge with those of the Birmingham Wire Gauge, &c.

NOTE.

...

Sizes which differ from those in the first column by more

than 002 of an inch are marked thus ** ; those of which the difference exceeds 001, thus *. All others either correspond exactly, or are within oor of an inch.

TABLE II.

Belgian Zinc Gauge.

No.. Approximate thickness in de

cimals of an inch Ditto

in millimetres

In.

I

2

3 4 5 6 7

891

ΙΟ II 12

002 004 006 008 010 012 014 016 018 020 023 026

05 10 15 20 25 30 35 40 45 50 58 ·66

No. 13 14 15 16 17 18 19 20 21 22 23 24 25 26 029032 037 043 048 053 058 063 070 077 084 091 098 105 Mm. 74 82 95 108 121 134 147 1 60 1.78 1962 14 2 32 2.50 2.68

NOTE.-Ordinary roofing thicknesses' are from No. 13 to No. 18.

TABLE VIII.

Table of Change Wheels for Screw-cutting Lathe, with
Leading Screw of Three Threads to an Inch.

(Number of Wheels required = 18.)

NOTE. The wheels of which the number of teeth in the above table are in thick type only need be adhered to. For the others, which are idle wheels, any which can be got in may be substituted.

Where two numbers occur in one column the wheels are to be connected together, and work on the same stud, the second one gearing with the wheel on the leading-screw.