Updated Camels & Camelbacks


Just in case you missed a post, from a year or two back, the innovative design and use of “Camelback Locomotives” – a style that was very popular on US railroads for many years.

The heading image is from the ‘Locomotive Dictionary 1916′  and shows one of the superb “Atlantic Type” 3-cylinder simple locomotives built and operated by the Philadelphia & Reading company, for passenger service.  Many thousands of “Camelbacks”, also known as “Mother Hubbards” were built by over 30 railroads, but it is the design of the firebox that is key to its success.


Philadelphia and Reading Railway. One of the large Vauclain Compound “Atlantics” used by the Phildaelphia & Reading on high speed passenger trains.                                                             Photo from:  Howden, J.R. (1907) The Boys’ Book of Locomotives, London: E. Grant Richards,  Public Domain, https://commons.wikimedia.org/w/index.php?curid=10548075 

There were two different types of locomotive with a centre cab, on top of the boiler – the earlier design built by Ross Winans in the 1840s, were simply known as “Camels”, but the later design with a new, and innovative design of firebox.  This also appeared initially on the Philadelphia and Reading Railroad, with the wide grate of the “Wooten Firebox”  its key component.  The design was patented by John Wooten in 1877.

I’m afraid an error crept into the original post, but I am grateful to one of my readers Jim Hansen for identifying this, and as you can see the original post has now been updated.

Original Patent Ref.

“Not all of these were successful and a clear description of the Wootten boiler is contained in the US patents, No. 192,755 (1877), 254,581 (1882) and the last changes under patent No. 354,370 (1886).”

Correct / Updated Patent Ref.

“Not all of these were successful and a clear description of the Wootten boiler is contained in the US patents, No. 192,725 (1877), 254,581 (1882) and the last changes under patent No. 354,370 (1886).”


A sectional view of the Reading’s 4-4-2 ‘Camelback’, originally shown in the 1916 “Locomotive Dictionary”

Having a look at the US Patent Office and searching for that particular patent reveals it expired in November 1998 – “due to failure to pay maintenance fees”.

For a more detailed look, why not follow this link:


It is a good read.



North American Steam


As is well known, steam power was invented and developed in Britain country for both stationary and locomotive purposes. Its introduction and use in the United States very likely came about as a result of illegal activity here in England. At around the end of the 18th and beginning of the 19th century, it was deemed an offence by ·the government of the day to transmit any information about the development or use of steam power to North America. In fact it was punishable by a one-year prison sentence in addition to a £200 fine! But, evidently news of James Watt’s success was transported across the Atlantic it would appear that industrial espionage is not a modern phenomena!

The first practical use of steam power, as applied to railways, in the USA, was first witnessed in the shape of locomotives imported from England by the Delaware & Hudson Canal Co., which operated a sixteen-mile horse and gravity operated coal railway in Pennsylvania. The first steam locomotive to run in the USA was in fact the English built “Stourbridge Lion”.

Replica Stourbridge Lion - United_States_National_Museum_(1956)_(14781532311)

A replica of the first steam loco to run in the USA – built in 1932 by the Delaware & Hudson Corp.   Photo: Internet Archive Book Images https://commons.wikimedia.org/w/index.php?curid=43475790 

Best friend

Built at West Point Foundry, the “Best Friend of Charleston” was the first home built steam loco for a US railroad. Photo courtesy Norfolk Southern Corp.

The first American built locomotive to be operated by an American railroad, was built at the West Point Foundry in 1830 and made its inaugural run for the South Carolina Canal and Railroad Co. of Charleston, on Christmas Day 1830. The locomotive was appropriately named the “Best Friend Of Charleston”. In appearance it hardly resembled a steam locomotive as we know it at all, powered by a vertical boiler positioned behind the driver, driving four coupled wheels it was not entirely dissimilar to the rather less successful “Novelty” locomotive, entered for the Rainhill Trials in England the previous year. But, it was a beginning, from which the North American steam locomotive was developed, ultimately to produce some of the World’s largest and most powerful steam locomotives ever to be built.
 In the early years of railway development, steam locomotive design in the USA progressed along similar lines to that of their European counterparts.

But then, there came to be a number of what at first could be seen as small, technical differences, providing a divergent path along which North American loco. design progressed. One of the principal foundations to this alternative to the British school of design, was the predominant use of bar frames as the principal technique of chassis construction, whereas in Britain, plate frames were the preferred method. Although bar frame techniques were actually first Introduced in the U.K. by Edward Bury, their development in the USA resulted ultimately in the use of techniques for manufacturing the chassis or frames of steam locomotives as enormous one piece castings. In many cases with cylinders and ancillary items of equipment ”cast on”. Style, an arbitrary idea in itself, was possibly the one most obvious difference between North American and British types.

North American 2 copy

The first cantilever trestle bridge in the USA, carrying the Cincinatti Southern Railroad across the Kentucky River, with a typical passenger train of the period. The “High Bridge” was opened in 1877, and rebuilt in 1911 – this view is of the original bridge. Photo courtesy Norfolk Southern Corp./RPB Collection.

Whereas in this country designers placed great emphasis on the aesthetic appeal of their machines, the era of elaborate ostentation in the USA reached a peak in the 1860s and. 70s. These then gave way to more logical concepts of the steam locomotive as a machine, where it was not a sin to trail pipework and fittings
 on the outside of the locomotive, making the working parts more accessible and maintenance infinitely easier.


A recreated Central Pacific # 60 steam locomotive at the Golden Spike National Historic Site in Utah          Photo: Mr Snrub at English Wikipedia. – Transferred from en.wikipedia to Commons., CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=3488328

To many of us though, thinking of nineteenth century design in the USA, immediately there comes to mind the wood burning 4-4-0 types, replete with ‘cowcatchers’, ornate bell and enormous chimneys. (Diamond stacks as they were known.) These locomotives were a tradition, if not a legend of North American railroads, and engendered a folklore and many legends of their own., from ‘Casey Jones’ to the ‘General’. The latter, in particular, having quite an entertaining history, culminating in its seizure by Union forces during the Civil War. The elaborate ornamentation of some of those mid-nineteenth century designs achieved well nigh indescribable levels, with gold plated scrollwork and paintwork and lining schemes that would have done justice to any regal palace!

By 20th century standards such locomotives were small, yet it’ was with just such engines as these that the vast mid-west and western seaboards of the USA were penetrated. Possibly the most outstanding achievement being the linking by rail of both east and west coasts at Promontory, Utah on May 10th 1869.

Alabama Southern 4-6-0 - 1905

Typical of US motive power at the beginning of the 20th century was this 4-6-0 on the Alabama Southern Railroad in 1905.    Photo by: By Internet Archive Book Images. https://commons.wikimedia.org/w/index.php?curid=43245503

The locomotives of the Central and Union Pacific Railroads were brought
 to within feet of each other and the ceremony completed by driving in a golden spike. From this point, railroading in the USA entered a period of explosive growth, as the government endeavoured to foster settlement of the West. New routes and companies sprang into existence, almost on a par with the ”Railway Mania” period in this country. In terms of Locomotive design though, there the resemblance ended. Railway companies in this country, for the major part, relied on their own designs, whether built in their own workshops, or by contractors. In the USA however, contractors to a much greater extent were relied upon to produce the designs as well as constructing the engines.

There emerged the idea that locomotive manufacturers as specialists in design and construction of steam locomotives would develop their own ranges of ‘standard’ designs, to be bought virtually, “off the peg”. Naturally there were exceptions, though in the sphere of technical development, the manufacturers were often first in the field. This approach was not unknown in this country, but developed to a much greater extent in the USA. A resultant feature being that whereas here it is traditional to refer to a class of locomotive by its owner and designer; in the USA it is almost invariably that of the manufacturer. The names of which were virtually household in this country also; Baldwin, Lima, Alco, etc. Many of these companies’ products were owned by almost all railroads, where the manufacturer, being a specialist, designer and builder, could supply in greater numbers than could the railroads, who were left free to concentrate on the business of carrying passengers and freight.

In the early years of the 20th Century, locomotive design in the USA was moving towards progressively larger types, with which, ultimately, that country became world famous. Its largest locomotives though, owed their development to a French engineer. These were enormous articulated designs, capable of hauling the heaviest of loads, and often in many cases, their tenders alone were larger then the largest British Pacific locomotives, indeed, particularly with the articulated types of the Union Pacific and Norfolk &Western Railroads, even the fireboxes could be bigger than an average living room.

AAR 7 copy

A picture to evoke nostalgic memories of steam, as a pair of Northern Pacific’s giant Mallet articulated locomotives stand in the yards at Missoula, Montana, and ready to handle the huge transcontinental freight working. Photo courtesy; Association of American Railroads.

The most popular form of articulation in N. America was the Mallet arrangement, whose originator was the French engineer M. Anatole Mallet. Basically it consisted of two separate chassis supplied by a single boiler, the leading chassis being pivoted about, the rear. Principle wheel arrangements of this design were of the order of 2-8-8-2, 4-6-6-4etc. Although originally designed to make use of compounding arrangements, most of the N. American types were simple expansion machines, Such locomotives were designed primarily for heavy freight haulage, although on the Union Pacific, a smaller version of the enormous 4-8-8-4
 “Big Boy”, albeit a not much smaller 4-6-6-4 type, was intended for fast, long distance passenger turns. (Long distance on the Union Pacific, was the 5000 odd miles between San Francisco and Chicago). Many railroads in the USA used the articulated types, but there were of course some quite remarkable exceptions. Notably, on the Pennsylvania Railroad, whose rigid frame 4-4-4-4 and 4-4-6-4 locomotives, known forever as Duplexii, were of comparable proportions to the articulated types. Built during the “Streamline Era” and sporting an air smoothed casing, these were really spectacular designs.

C&O Class K4 at Chief_Logan_State_Park_-_C&O_2755

C&O Class K4 at Chief_Logan_State_Park, as preserved at Logan, West Virginia. 92 of this 2-8-4 design were built for C&O, where they were known as the “Kanawha” type, and although a number of other railroads operated them, they were also referred to as the “Berkshire” type.     Photo By Brian M. Powell, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=9374221













Santa Fe 5011 Texas Class 2-10-4 No.5017

Santa Fe “5011” “Texas” Class 2-10-4 No.5017. Built by Baldwin in 1944, this example is now at Green Bay Railroad Museum, 8/70. Baldwin started building these in the 1930s, and they were the heaviest (247.5 tons) and most powerful (T.E. 93,000 lbs) “Texas” type ever built and also had the largest piston thrust (234,000 lbs) of any locomotive.                 By Hugh Llewelyn – 5017Uploaded by Oxyman, CC BY-SA 2.0, https://commons.wikimedia.org/w/index.php?curid=24387751

Steam in the USA reached its zenith in the, early 1930’s, at the beginning of that decade there wore over 56000 locomotives in service. It was at this time, marking the ·beginning of the “Streamline Era”, that some of the most impressive and largest locomotives were built. The largest, as we have noted, were the mammoth Mallet articulated types, for heavy freight haulage. On the passenger side, as in this country, passenger schedules with improved timings, demanding higher speeds, dictated the design of more powerful locomotives, capable of handling the heaviest loadings. But, whereas in this country passenger locomotive design reached a peak with the heavy 4-6-2 Pacific types, in the USA. passenger locomotives became even larger. Amongst the largest and most impressive of these were perhaps the 4-6-4 Hudson and 4-8-4 Niagara types for the New York Central Railroad.

North American 1RPB Photo 488 NYC Niagara No 6000

Classic North American steam locomotives for express passenger or freight services, are perhaps nowhere better illustrated by the streamlined 4-6-4 “Hudson” and 4-8-4 “Niagara” designs for the New York Central Railroad.

Photos: Assoc of American RRs / RPB Collection

Of these, the former was probably the more popular for passenger haulage, the design being used in quantity by most, if not all of the U.S. Class 1 railroads. The New York Central’s design was possibly the most successful, though seeing a variety of improvements and alterations from its first inception, the overall design remained the same, its capacity for sustained high speed haulage of heavy loads was surpassed by few, if any others.

It might well be imagined that all North American steam locomotives were of massive proportions, such however would be far from the case, though it must be said that even the “Branch Line” locomotives were more often than not
 as large as many British main line types. Again, not all locos. were conventional in design. Apart from the several narrow gauge lines, the USA possessed some quite unique examples in the “Shay” and “Heisler” geared drive locos. intended for use on logging railroads, where the gradients, curves and clearances were often extremely severe.

The changeover from steam to diesel traction was begun earlier than here, but unlike this country, when the final elimination of steam took place, the railroads had a fairly lengthy experience of the new motive power behind them. The first diesel appeared on the Central of New Jersey Railroad in 1925. It was not an immediate success however, its power to weight ratio made it uneconomic, but these were problems of course, that were subsequently overcome, since 27 years later, the number of diesel locomotives outweighed that of steam. An interesting comparison can be made with these figures; in 1929 there were only 22 diesels in service, compared with 56,936steam types, by 1955 diesels were in the majority with 24,786 and only 5,982 steam. For steam, the worst years and complete elimination came between 1955 and 1962. During this period the number of diesels rose by 3,318; steam locomotives being reduced from 5,982 to 51! There are still, at the time of writing, seven steam locos in service on Class l railroads, six of which are narrow gauge types.


Further Reading & Useful Links:

From Railway Matters: New York Central Giants