Early signaling on the N&W
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Wed Oct 29 14:18:54 EDT 2014
Such a series of questions Mr. Cochran has laid out for me! But I will do
my best, giving you, of course, the historical context of the whole issue.
First, however, it must be observed that almost all railroad procedures
were in flux over the years. Two good examples come to mind: (1) Colors
originally used on signals were Red, Green (for Caution) and White (for
Clear.) Yes, you read that right. The glass industry had great difficulty
in "holding the chromatic standards" in the manufacture of yellow glass
until about 1913, and railroads would not adopt Yellow as a standard signal
color for that reason. The shift from R/G/W to R/Y/G as standard signal
colors happened very gradually between about 1896 and 1917, depending on
the road (C&NW made the shift about 1896, PRR in 1917.) (2) The second
example of evolution in practice was the change in colors on the rear end
markers on trains. Up until 1911 (if memory serves me correctly,) N&W rear
end markers sported Green and Red glass or simply a green flag "by day.".
By contrast, VGN cabooses carried YELLOW FLAGS on the caboose "by day"
right up until the N&W took over. So, things changed greatly over the
years, and varied from railroad to railroad.
Likewise, the whole process of "blocking trains" evolved over the years.
The 1898 N&W Rule Book is pretty much a home-brew affair, but the 1905 N&W
Rule Book is straight "standard code" as published by Train Rules Committee
of the ARA (predecessor to the AAR.) In other words, the N&W had adopted
"industry practice" by 1905.
If you want to understand the history and evolution of the "blocking" of
trains, you must reach back further than just the N&W years, because the
N&W did not invent blocking. Blocking (which later came to be called
"Manual Blocking" by most railroads, but which the N&W called "Telegraph
Block") was invented in 1864 by Ashbel Welch, Superintendent of the
Belvidere-Delaware RR, which operated out of Trenton, NJ. To understand the
roots of blocking, you must read Welch's 1865 paper, "Safety Signals"
(which I can send you.)
A second indispensable background piece is the PRR Rule Book of 1874 (which
is available on-line.) I say it is indispensable because, in preparation
for the great crush of traffic the PRR anticipated in connection with the
1876 Centennial in Philadelphia, the PRR instituted "block rules" on its
entire main line from New York to Pittsburgh, being the first railroad in
the country to do so on such a scale. And those 1874-1876 practices are
beautifully spelled out in PRR's 1874 Rule Book.
So, why is the 1874 PRR Rule Book relevant to a discussion of N&W
practices? It's because the leading light on the Shenandoah Valley RR (and
later N&W) was Joseph H. Sands, who had been an official on the PRR, and
who brought with him probably more influences than we will ever know. Sands
brought the "blocking of trains" from his former employer, and I am of the
opinion that he also brought the "Tuscan" red paint scheme for the SV RR's
passenger equipment, and even the classification of paper forms, one of
which categories was "CT," which meant "Conducting Transportation" on his
former road. After the N&W RR purchased the SV RR in 1890, Sands became the
top operating person on the newly combined railroad... and thus his ideas
Third, in addition to the above mentioned sources, Mr. Cochran's questions
will require a reading of the N&W Rule Book of the particular period in
which he is interested, AND the Special Instructions published at the back
of the various Division Time Tables. The Rule Books will gave the general
scheme, and the T.T. Special Instructions will give the particulars of
implementation on the various territories.
Fourth, to get a more complete picture, one should study an N&W typescript
titled "Block Signals in Use on the Road, September 1896." I have donated a
digitized copy to the N&W Archives, and will be happy to send you the file
in PDF format.
Fifth, one needs to read "Instructions Governing the Use of Automatic Block
and Interlocking Signals, Norfolk & Western Railway Co., Effective April 1,
1907." I have a copy of this 32 page booklet, and really need to digitize
And finally, there is one more thing you would need for a complete answer
to your questions, but which you will never find. And that is the
dispatching practices which were given to the Train Dispatchers. On the
last big railroad I worked for, I often gave the Train Dispatchers written
protocols on how they would handle certain situations. We even codified
these into a "Train Dispatcher's Manual of Practices" and a copy was kept
at all seven of our Division's dispatching desks. From the standpoint of
eliminating confusion, there is nothing worse than having a crew handled
one way on one territory, and a different way on another territory. Many
times train crews would ask me, "Why do the Train Dispatchers do
so-and-so...?" And my answer would be, "Because they have written
procedural directives which you never see."
Given all the above long-winded prolegomena concerning sources and
background, let's move to the specifics of Mr. Cochran's questions... as
best as I can answer them from the 1898 and the 1905 N&W Rule Books, and
the other surviving literature.
(1) QUESTION: " Under the permissive system, did an operator [only give a
Permissive] if the caboose of the preceding movement had passed him a
certain number of minutes previously?"
ANSWER: Both the 1898 Rule Book (Rule 514) and the 1905 Rule Book ook (Rule
712) requires that a train entering a Permissive Block must be spaced five
minutes behind the preceding train (and this was done by holding the
station semaphore at Red for five minutes.) Neither of these editions of
the Rule Book mention a "space interval" (footage) to be observed between
(2) QUESTION: " Was the semaphore used for manual blocking the same as the
'train order' signal that you sometimes see in station photos as late as
ANSWER: The simple answer is, No. But this is a thicket because of all the
changes over the years, and I want to give you some historical background.
The contours of the problem are as follows:
(a) I do not know if the original original N&W "RailROAD" blocked trains,
because I have never seen a Rule Book from that company. But I would doubt
that they blocked trains because they did not have the two problems which
led to the necessity for blocking, namely high speeds and heavy traffic
density. Rather, I believe the N&W "RailROAD" was operated purely by the
"Time Table / Train Order" method of operation, without blocking. Under
such a system, the semaphore at the station was only a Train Order signal.
(b) Later on, apparently after the advent of Joseph H. Sands on the
property, the station semaphore came to be used as BOTH the Train Order
signal AND the Block signal. If you read the 1896 typescript "Block Signals
in Use on the Road, September 1896," you will see that in certain locations
the station semaphore was being used as the Block signal, BUT THE TRAIN ON
ORDER SIGNAL WAS A RED FLAG STUCK IN A POST, OR ON THE SEMAPHORE SIGNAL
MAST, OR ON THE STATION BUILDING (the red-flag-on-a-post being a very, very
old practice in railroading) !
(c) Some time prior to late 1896, most N&W station signals were changed to
two-arm semaphores. A "Permissive Block Arm," green in color, was placed
below the top arm. Rule 514 in the attached scan from the 1898 rules, gives
an excellent overview of how the two semaphore arms worked in conjunction.
(Note that the 1898 N&W Block Signal Rules were not adopted seriatim from
the 1896 edition of "The Standard Code of the American Railway Association
- Train Rules, Block Signal Rules." They are worded entirely differently,
and are of much greater length than the ARA rules on the same subject. It
is possible that implementing "the blocking of trains" on the N&W was a
personal project of Mr. Sands, and that he himself have wrote the N&W rules
on this subject.)
Further to confuse us, photographs from the Valuation Era (1914-1921) show
different shapes on the ends of the blades of the top and bottom semaphore
arms. In "standard" ARA recommended practice, a square end on a semaphore
indicated a block signal or a home signal, and a "scalloped" end (end cut
out in a half-moon shape) indicated a Train Order signal. Some N&W
Valuation photos show a square end on both semaphore arms; some show a
scalloped end on the bottom arm. And the N&W Rule Books did not show signal
aspects until 1917. So if you ever figure all this out, please let me know
To give a short and direct answer to the question, it can be said that the
semaphores in photographs of main line stations in the 1950s >> IN
AUTOMATIC BLOCK SIGNAL TERRITORY << are simply Train Order signals. Once an
Automatic Block Signal System was installed, there was no further need for
a Manual Block signal to manually block trains. (Also, note that they had
scalloped ends on the semaphore arms, indicating they were Train Order
I would love to know which N&W branch was the last to be operated under
Manual Block/Telegraph Block rules, but I have never found the answer.
In the above, you may have picked up on a bit of "creepage of categories
and nomenclature" that occurred over the years. At the beginning, there was
only a "station signal." Later there is a distinction between "Train Order
signals" and "Block signals." So, when one sees a really old photograph of
an N&W station sporting only a single semaphore arm, he has to ask, Is that
semaphore a Train Order signal, a Block signal, or both? And there is no
simple answer to this question. The answer will come by determining the
date and the rules/procedures in effect at that time.
I am attaching PDFs containing the "Telegraph Block" rules from the 1898
and the 1905 N&W Rule Books. They area a fascinating read for anyone
interested in the development of railroad operating practices.
-- abram burnett
advocate-at-large for the "signal arm" :-)
Sent to You from my Telegraph Key
... better than AT&T 4G LTE
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