0-4-0, a standard design of its English maker, Robert 
Stephenson & Co. The engine had proved entirely 
unsatisfactory for the Baltimore and Susquehanna, and 
had been rebuilt in October 1832—only a few months 
after its delivery—as a 4-2-0 wheel arrangement. 
By 1846, however, it was found too small for further 
service and accordingly was taken into the company 
shops for major remodeling. Mullholland fashioned 
a powerful 13-ton 0-6-0, nearly twice the weight of 
the original Herald, from which only the boiler was 
used. Other major features of this remodeling were 
a gear drive for power and low speed, and a lateral- 
motion arrangement for each driving axle to permit 
navigation of sharp curves. The engine was in- 
tended for the movement of trains through city 
streets between the railroad’s Baltimore 
terminals. The Herald was still in service in 1857, 
but was sold for scrap two years later. 
Millholland’s gifts as mechanic and innovator first 
various 
received notice in a report by the American Railroad 
Journal for November 6, 1845, on the use of cast iron 
for making crank axles. Inside-connected engines, 
which were then popular, were fitted with wrought- 
iron crank axles. Although wrought iron was the 
strongest material available, it was not only costly, 
but its variable quality and fibrous character made it 
unreliable for use in crank axles. These broke 
frequently, creating a costly hazard and _ serious 
accidents. 
Millholland’s insistence upon cast-iron crank axles 
seemed preposterous because the metal was brittle 
and unable to withstand great impact stresses. He 
eschewed ordinary cast iron, however, and insisted 
on the best cold-blast Maryland iron—the kind used 
for cannons and car wheels—which had a tensile 
strength of about 30,000 pounds per square inch. 
In its report, the American Railroad Journal noted 
that Millholland’s cast-iron crank axle had been used 
successfully since June 15, 1845. The engine in 
question, unidentified except that it was built in 
Lowell, was unquestionably one of the light Locks 
and Canals locomotives mentioned above. It was 
described as having a leading truck, a single pair of 
driving wheels, and a pair of trailing wheels, making 
it a 4-2-2. The crank axle weighed 1150 pounds 
before turning, which compared favorably to a 
similar unmachined wrought-iron axle weighing 1164 
pounds. It had been cast by J. Watchman of Balti- 
more at a cost of $69, whereas the wrought-iron axle 
cost $291 before machining. Not only was the cast- 
iron crank cheaper, but it was equally as strong as the 
6 BULLETIN 252: 
wrought-iron one. The American Railroad Journal con- 
tinued its report: 
A few evenings since, the engine with the cast iron 
crank axle, was, together with its tender, thrown entirely 
off the track, by a large hog getting under the wheels 
behind the cow-catcher—no damage having been done 
to any part of the engine, it was thus shown that the cast 
axle can bear without injury the sudden and violent 
strain to which it was subjected by this accident, as well 
as the wrought iron crank axle. There is therefore good 
reason for believing that this improvement, which will so 
materially reduce the cost of replacing a broken crank 
axle, may with perfect safety be introduced into general use. 
The Baltimore and Susquehanna subsequently 
fitted its other inside-connected engines with cast-iron 
crank axles. No evidence exists that other roads 
followed suit, but the Baltimore road seemed well 
pleased with Millholland’s innovation. In a letter to 
Robert Stephenson and Co., dated March 8, 1850, 
Robert S. Hollins, secretary of the Baltimore and 
Susquehanna, stated: ‘“‘Our preference is the Cranked 
Axle Locomotive, but repeated breaking of the axle; 
Every Locomotive having broken one or more, we 
were induced to try cast tron, and after an experience 
of 5 years, we have adopted them entirely, never yet 
having broken a Cast Iron Crank Axle.” * This state- 
ment, made two years after Millholland had left the 
Baltimore and Susquehanna, testifies that the cast- 
iron crank axle was a success on its own merit and not 
merely because it was a ‘‘pet”’ of the presiding master 
mechanic. According to Millholland’s eldest son, 
James A. Millholland, one of these crank axles was 
sent to his father years later, presumably in the 1860’s, 
after the engine had been scrapped.° This trophy 
laid around the Philadelphia and Reading shops for 
some years, only to be junked during a clean up. 
In addition to rebuilding existing machines and 
developing the cast-iron crank axle, Millholland built 
two new locomotives at the Bolton shops. The first 
of these identical machines, the General Taylor, was 
completed in October 1846; the other, the Wm. H. 
Watson, in March 1847.° Intended for freight service, 
these machines were large for the times, each weighing 
4 Engineer (May 29, 1914), vol. 117, p. 601. 
° Letters dated May 11 and 18, 1888, from James A. Mill- 
holland to J. E. Watkins, a curator at the Smithsonian Institu- 
tion. 
® American Railroad Journal (December 19, 1846), vol. 19, 
p- 811, states that the Watson ‘twas lately built.” The March 
1847 date is given in the Baltimore and Susquehanna’s annual 
report for 1849. 
CONTRIBUTIONS FROM THE MUSEUM OF HISTORY AND TECHNOLOGY 
