The Alphabet Route
(4-6-6-4's) and Potomacs (4-8-4's) had steamboat whistles with 5* chimes.
These whistles were operated with an air valve in the cab instead of a rope
which made them virtually impossible to blow in any manner except wide open.
The I-2 (2-10-0) class engines had similar whistles but with manually
operated valves. Similar, if not identical, whistles were used on most
or all of the 800s (2-8-0's) and the Pacifics (4-6-2's). The 900s
(articulated 2-8-8-2, 2-6-6-2, and others) had chime whistles with rather
long bells but not quite the same as those on the H-9s and I-2s. The
whistles on the H-7 (2-8-0) class engines were long bell single note hoot
whistles. They were not shrill if properly adjusted. The Elkins
shop whistle was reprotedly off of a 700 and was quite pleasent sounding.
Some of the older classes of 2-8-0s like the 600s also had whistles similar
to these. The whistles on the H-8s (2-8-0) and I-1s (2-10-0) are very
hard to see in photos but appear to be short chime whistles. The shays
had similar whistles. These should have been sharp chime whistles but
not necessarly shrill. Even photos of little 348 show what appears to
be an old chime whistle that likely sounded very nice.
whistles were not necessarly what the engines were delivered with.
Some older photos of the I-2s show short chime whistles instead of the
longer steamboats of later years. There is evidence that the K-2s had
3 different whistles in their lifespan. There seemed to be little variation
between the classes unless it was on the older engines. There were few
if any shrill whistles on the WM.
The Western Maryland Railway
Historical Society put out a 33rpm long play album of WM steam titled "Fast
Freight Rolling". Several classes of steam whistles are heard on
*the source of this document was uncertain that these
were 5 chime whistles, but suggested that it was most likely. They
were definitely 3+ chimes.