N&W Signal Statistics, 1908

[NW Mailing List]

"The Railway Signal Dictionary," 1st Edition (Compiled for the Railway Signal Association by Brayman B. Adams and Rodney Hitt, New York: Railway Signal Gazette, 1908; 560 pages plus additional pages for charts and advertising) gives signal statistics for all U.S. railroads, in tabular form. The tables are marked "January 1, 1908," so these statistics were assembled sometime in 1907. The source of the information is most likely the annual reports that railroads were required to render to the ICC. Statistics given for the N&W are as follows: 

Single Track equipped with Automatic Block Signals - 1.0 miles 
Two or More Tracks equipped with Automatic Block Signals - 29.3 miles 

Single Track signaled by non-ABS - 1506.7 miles 
Two or More Tracks signaled by non-ABS - 205.5 miles 

Total Miles of Passenger Line Operated - 1829.3 miles 
Percentage operated under a Block Signal System - 95.3% 

Kinds of Automatic Block Signals Employed: 

Unenclosed Disc (clockwork) - 0 miles 
Enclosed Disc - 0 miles 
Electro-pneumatic - 0 miles 
Electric Motor - 18.5 miles of road, 35.0 miles of track 
Electro-gas - 0 miles 

There is one other juicy tidbit about the N&W. The Dictionary states: "On the following sections of single-track road the block signal system (manual) is used only for the protection of trains from rear collisions: CB&Q 5,165 miles, Michigan Central 1,003 miles, Missouri Pacific 227 miles, N&W 727 miles, Northern Central 187 miles, Wabash 773 miles." 

Now this is indeed a fascinating piece of information... that only following moves were "blocked" - opposing moves, which would have been governed by TimeTable rights and Train Orders, were not "blocked." This is something that would not be obviously stated in the TimeTable Special Instructions, but rather would be mentioned only in an oblique way by an abstruse sentence saying something like "Between ___ and ___, the second paragraph of Rule 318 will apply." 

I think those miles of double track operated by Automatic Block Signals were probably east of Bluefield, on the Radford Division. 

It would be VERY interesting to know the location those 85.96 miles (4.7% of 1829.3) of "passenger line" operated without the protection of manual blocking. (Perhaps those were branch lines where only one train, maybe a mixed train, operated on a round-trip basis.) 

The Signal Dictionary went through one more edition, published three years later in 1911. I'll try to find time to compare how the N&W's signal situation had changed over that period of time. 

It is sad that there doesn't seem to be any information on when the N&W began "blocking trains" by manual means. I suspect that principle of operation was brought in by the Shenandoah Valley RR management, who had come from the PRR, which began blocking trains in 1876. It is doubtful that either the AM&O or the Norfolk & Western RailROAD had sufficient traffic densities to require the blocking of trains. 

-- abram burnett 
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://six.pairlist.net/pipermail/nw-mailing-list/attachments/20121124/ffd76518/attachment.html>