The Conception of the Contemporary Standard Express Passenger Locomotive by New Zealand Engineers and its World-
ONE OF THE FIRST “PACIFICS” 4-
THE dawn of the current century found the railways of the world once more confronted with the eternal problem of Traffic versus Motive Power. The “Atlantic” was holding sway, but it did not completely solve the issue; indeed, many locomotive engineers maintained that it did not present a sufficient advance upon the well-
As the result experiment was carried out at high pressure to meet the situation. Various wheel classifications within the limitations which ruled were tried in turn, but one and all led to the 4-
During the opening weeks of 1901 the Baldwin Locomotive Company were asked to submit a design for a locomotive to burn lignite coal. The American company suggested the use of a wide fire-
The design, when investigated by the American locomotive technicians, was discovered to be a new type from the addition of a trailing axle to the ten-
SKETCH DESIGN OF THE FIRST “PACIFIC”, NO. 338, OF THE “Q” CLASS, TO RUN ON THE NEW ZEALAND GOVERNMENT RAILWAYS, 1901.
The locomotive was built, and the first of the fleet of thirteen, Nos. 338 to 350, ordered from the Philadelphia works, was delivered to the New Zealand Government late in 1901 to form the official class “Q”. They are identical, with cylinders 16 by 22 inches connected to the six-
The leading truck carries 21,280 lb; the three driving axles 68,880 lb; of the latter weight 22,624 lb are borne by the first and third axles, and 23,632 lb by the central axle; the trailing axle bears 17,360 lb. The eight-
From the fact, that this locomotive was evolved from the ten-
The “Pacific” satisfied the requirements of the New Zealand system very effectively, but did not arouse widespread enthusiasm elsewhere, for the simple reason that the “Atlantic” had not been carried to its limits of development at that date. The power issue reached its really acute stage upon the American continent with the coming of the all-
A BALDWIN “PACIFIC” OF 1903. It was built for the Chicago and Alton Railway to haul the heavy excursion trains to the St. Louis Exhibition. The driving wheels are 80 inches in diameter, overall length, 62 feet; tender capacity, 8,400 gallons of water and 9 tons of coal; the weight in working order is 130 tons.
The railway companies, impressed with the successful operation of the 4-
The “Pacific” made its debut in Great Britain during 1908, the Great Western initiating the movement with “The Great Bear” with four cylinders, 15 by 26 inches, working at a pressure of 225 lb of steam raised in a boiler 23 feet in length by 72 inches, tapering to 66 inches, in diameter. The total heating surface, including superheater, is 3,154 feet. The driving wheels are 80½ inches in diameter; tractive effort 27,800 lb.
THE FIRST BRITISH EXPRESSION OF THE “PACIFIC” APPEARED ON THE GREAT WESTERN RAILWAY, 1908. It has 80½-
The Great Northern (now part of the London and North Eastern Railway), which introduced the “Atlantic” to Great Britain, turned to the “Pacific” for the haulage of the heavy Scottish expresses in 1922. This locomotive “Great Northern” has three cylinders 20 by 26 inches. The heating surface is 3,455 square feet -
GIANT “PACIFIC” INTRODUCED UPON THE GREAT NORTHERN RAILWAY FOR ITS SCOTTISH EXPRESS TRAFFIC, 1922. It has 80-
Upon the introduction of the ten-
These “Pacifics” are essentially high-
POWERFUL “PACIFIC” INTRODUCED ON THE PHILADELPHIA AND READING RAILROAD, 1918. This type was built to maintain the 55 minutes’ service between Camden and Atlantic City, when the introduction of heavier rolling stock proved to be above the capacity of the “Atlantics”.
The “Pacific” has also found widespread favour upon the Canadian railways, owing to the similarity of the conditions prevailing in both countries. Those on the Canadian Pacific expresses, which were built in the workshops of the company, have cylinders 25 by 30 inches, and driving wheels 75 inches in diameter. The boiler has a maximum outside diameter of 88 inches, carrying steam at 200 lb per square inch. The firebox totals 111⅛ inches in length by 83⅜ inches in width. The water-
AN EXPRESS “PACIFIC” OF THE CANADIAN PACIFIC RAILWAY. It has an overall length of 67 feet 1 inch; 75-
Nearly every American system has its fleet of “Pacific” locomotives, standardized for express passenger service, and many of these are magnificent expressions of locomotive engineering. Among them may be mentioned those of the Pennsylvania Railroad. These have cylinders 27 by 28 inches, using steam at a pressure of 205 lb, with driving wheels 80 inches in diameter. The boiler, of the Belpaire wide fire-
PENNSYLVANIA RAILROAD’S “PACIFIC” (K4s TYPE) FOR EXPRESS PASSENGER SERVICE. It has cylinders 27 inches in diameter by 28-
The “Pacific” has met with widespread recognition upon the European continent, notably in France; for the State railways of that country an imposing fleet was built by the North British Locomotive Company during the Great War. The French locomotive industry suffered from severe disturbance as the result of hostilities and the pressure of the demand for materiel de guerre in motive power. The British-
The coupled driving wheels have a diameter of 76⅜ inches; that of the front bogie truck wheels is 37 13/16 inches, and of the trailing wheels 48⅜ inches. The rigid wheel base is 13 feet 51 7/16 inches; of engine 35 feet 9 3/16 inches; of engine and tender 64 feet 3⅜ inches. The tender, mounted on two four-
NORTH BRITISH LOCOMOTIVE COMPANY’S “PACIFIC” BUILT FOR THE FRENCH STATE RAILWAYS DURING THE WAR. Ready for the road, the locomotive scales 328,496 lb. It has a boiler pressure of 227 lb per square inch, and at 50 per cent of the latter exerts a draw-