|
| | | | | | |
| 3- 1/8 | 3- 1/16 | 3- 5/8 | 4-27/64 | 1- 9/16 | 1-15/16 |
| 3- 1/2 | 3- 7/16 | 4- 1/16 | 4-61/64 | 1- 3/4 | 2- 3/16 |
| 3- 7/8 | 3-13/16 | 4- 1/2 | 5-31/64 | 1-15/16 | 2- 7/16 |
| 4- 1/4 | 4- 3/16 | 4-29/32 | 6 | 2- 1/8 | 2-11/16 |
| | | | | | |
| 4- 5/8 | 4- 9/16 | 5- 3/8 | 6-17/32 | 2- 5/16 | 2-15/16 |
| 5 | 4-15/16 | 5-13/16 | 7- 1/16 | 2- 1/2 | 3- 3/16 |
| 5- 3/8 | 5- 5/16 | 6- 7/32 | 7-39/64 | 2-11/16 | 3- 7/16 |
| 5- 3/4 | 5-11/16 | 6-21/32 | 8- 1/8 | 2- 7/8 | 3-11/16 |
| | | | | | |
| 6- 1/8 | 6- 1/16 | 7- 3/32 | 8-41/64 | 3- 1/16 | 3-15/16 |
| 6- 1/2 | 6- 7/16 | 7- 9/16 | 9- 3/16 | 3- 1/4 | 4- 3/16 |
| 6- 7/8 | 6-13/16 | 7-31/32 | 9- 3/4 | 3- 7/16 | 4- 7/16 |
| 7- 1/4 | 7- 3/16 | 8-13/32 | 10- 1/4 | 3- 5/8 | 4-11/16 |
| | | | | | |
| 7- 5/8 | 7- 9/16 | 8-27/32 | 10-49/64 | 3-13/16 | 4-15/16 |
| 8 | 7-15/16 | 9- 9/32 | 11-23/64 | 4 | 5- 3/16 |
| 8- 3/8 | 8- 5/16 | 9-23/32 | 11- 7/8 | 4- 3/16 | 5- 7/16 |
| 8- 3/4 | 8-11/16 | 10- 5/32 | 12- 3/8 | 4- 3/8 | 5-11/16 |
| 9- 1/8 | 9- 1/16 | 10-19/32 | 12-15/16 4- 9/16 | 5-15/16 |
|_________|_________|__________|__________|_________|_________|

The dimensions given for diameter at root of threads are also those
for diameter of hole in nuts and diameter of lap drills. All bolts and
studs 3/4 in. diameter and above, screwed into boilers, have 12
threads per inch, sharp thread, a taper of 1/16 in. per 1 inch; tap
drill should be 9/64 in. less than normal diameter of bolts.

The table is based upon the following general formulae for certain
dimensions:

Short diam. rough nut or head = 11/2 diam. of bolt + 1/8.
" finished nut or head = 11/2 diam. of bolt + 1/16.
Thickness rough nut = diameter of bolt.
Thickness finished nut = diameter of bolt - 1/16.
Thickness rough head = 1/2 short diameter.
Thickness finished head = diameter of bolt - 1/16.

* * * * *

AN ENGLISH RAILWAY FERRY BOAT.

[Illustration: AN ENGLISH RAILWAY FERRY BOAT.]

The illustrations above represent a double screw steam ferry boat for
transporting railway carriages, vehicles, and passengers, etc.,
des