gines came to the Cascade Division. Twenty-seven of these 4-8-2's were purchased in 1923 from Baldwin. These locomotives handled the through passenger service on the Great Northern and ultimately relinquished their job in the Cascades only because it was not economical for an electric locomotive to haul a steam locomotive over the 73 miles of electrified territory. In 1925 one of these, the 2517, became the first (and perhaps the only) steam locomotive to make the round trip from the Mississippi River to the Coast with no servicing other than that obtainable during ordinary fuel and water stops. The 2500-series Class P2 Mountain types hauled the cream of the Great Northern's passenger, mail, express, and silk trains until new Cascade Tunnel opened. Their 73-inch drive wheels were backed up with boiler capacity and cylinder dimensions that let them take eight cars up the 2.2 per cent grade to the tunnel without a helper and without dropping a pound below their designated 210-pound boiler pressure. These locomotives represented the first departure from the Belpaire firebox which had been standard on Great Northern locomotives since the 19th century. The Class P2 Mountain types had fireboxes of the radial stay design. No story of the Great Northern would be complete without mention of the famous silk trains. These usually consisted of 8 to 10 baggage cars loaded with raw silk bolts from Japan. This was a very perishable and extremely valuable cargo a single trainload could be worth in excess of 3 million dollars. The high value and perishability of the cargo called for the fastest of handling, and the Great Northern was known for the way it handled these trains. The GN's Pacifics or P2 Mountains usually hauled these trains, although occasionally the rebuilt Class E Ten-Wheelers were used. Perhaps the most notable of fast silk train runs occurred in 1924. At that time the world-famed Oriental Limited, the last word in luxury trains, covered the 1800 miles from St. Paul to Seattle in 60 hours; but even the new Oriental Limited, like every other train on Great Northern rails, got out of the way of a silk train, which had rights over everything. At 1:05 p.m. on August 13, 1924, Mountain 2512 left Seattle with 10 baggage cars of silk and a coach for the train crew. The 2512 took the train through to Skykomish where Consolidation 1101 tied onto the head end for the run EAST PORTAL of old Cascade Tunnel holds 5011 and 5010 in 1928 publicity classic. Courtesy of H. S. Ogden. up the Tye River Valley to old Cascade Tunnel. The Oriental Limited, because of the many speed restrictions on the almost continuous curvature of the line between Skykomish and Tye, averaged about 15 mph for this part of the run. With the speed restrictions eased, the silk train ran at almost 25 mph. The 1101 dropped off at the tunnel and 2512 continued on to Wenatchee, arriving there at 6:05 p.m. The schedule speed from Seattle to Wenatchee for the Oriental Limited was 23 mph. The silk train averaged 32, a remarkable performance. The train left Wenatchee behind another Mountain and the Cascade Division had finished its part of the job. Next day the word drifted west: the silk train had arrived at St. Paul 391⁄2 hours after leaving Seattle. At that time it was the fastest running time ever made from the West Coast to the Mississippi Valley, but as a record it lasted merely a half day. Eleven hours 18 minutes later Pacific 1447 wheeled nine cars of silk into St. Paul 38 hours 50 minutes out of Seattle. For 1924, when 60 hours was considered good time, 38 hours 50 minutes raised a few eyebrows in the railroad world. And in boosting those two trains up the Tye River Valley, the Cascade Division had more than contributed its part. The electrification continued to give good service right up to the end of the Second World War, when again traffic had increased to the point where more motive power was needed. GE designed and built what were then the most powerful singleunit locomotives in the world. Two of them were delivered to the Great Northern in 1947; each had 12 axles, all motored, with 735,000 pounds weight on drivers. The wheel arrangement was B-D-D-B. At first glance they appeared to be merely unusually long electric locomotives with a pilot truck at each end and the usual rigid motored driving truck. However, this was not the case. Even the "pilot" truck had both axles motorized. These locomotives enabled Big G to handle still heavier trains than had been handled before with single-unit locomotives. The older GE and Westinghouse locomotives continued in service, operating much as they had before. During World War II the Great Northern operated freight trains over the Cascade Division with three different types of motive power on the same train. A typical motive power assignment might call for three of the GE electrics (9000 horsepower) with a four-unit 5400 h.p. diesel-electric helper in the middle of the train and one of the big Class R 2-8-8-2 Mal lets pushing behind the caboose. Train consists handled by this motive power averaged about 120 to 125 cars and about 6000 tons. On the 2.2 per cent grade train speed was 17 mph, and excepting on one occasion when an air hose burst and the Mallet upended a caboose, the operation was trouble free. The Mallet pusher usually cut off on the run at the tunnel portal and the electric road locomotive with the 5400 h.p diesel helper went on through the tunnel. The Great Northern believes that this was the only instance of its kind in which three separate and distinct types of motive power were regularly assigned to the same train. IN the late 1940's the Great Northern began to take a serious look at diesel operation. The diesels were appearing on the west end of the system, and the westbound Fast Mail and the eastbound Empire Builder had been dieselized in 1945 between St. Paul and Wenatchee with 4000 h.p. locomotives. These same units were later used to power the new postwar Empire Builder in 1947. The electrics continued to haul the train from Wenatchee to Skykomish and the 2500 h.p. series 4-8-4's (which had been handling GN passenger trains since 1929) the rest of the way to Seattle. But steam power was on the way out, and in late 1947, nine 4500 h.p. three-unit diesel electrics took over the Oriental Limited and the Fast Mail. The Great Northern then began using the passenger diesels through Cascade Tunnel, eliminating the change of motive power at Wenatchee and Skykomish. Test trips indicated that the fastmoving passenger diesels could negotiate the tunnel successfully, but when the freight locomotives tried it, operating problems became immediately apparent. The tremendous heat generated by the exhaust gases of the relatively slow-moving eastbound freight diesels raised air temperatures in the tunnel to a degree that caused engine shutdowns. The exhaust temperature of a diesel engine is somewhere between 1000 and 1500 degrees Fahrenheit, depending upon how much heat the supercharger (if any) may have extracted. Four-unit locomotives are more than 200 feet long and, in a tunnel, the cooling water radiators of the trailing units in such a locomotive pull in a lot of air which has been heated by the exhaust gases of the preceding units. This is due to the fact that the locomotive creates a "piston" effect, pushing most of the air in the tunnel in front of it, leaving relatively little cool air to work its way around the sides of the trailing units and into the radiators. If the air going into the radiators is, say, 200 degrees, obviously it doesn't cool the diesel engine's water very much and the trailing unit's engine proceeds to overheat. When this happens, the engine drops to idle, the power goes off, and a cursing engineer finds himself trying to drag his train through the tunnel with three units. Of course, the speed drops further, the air gets hotter, and soon the next unit goes off the line, and so on. There have been cases in which trains stalled in tunnels as the units went down one by one with overheated engines. This situation is compounded when, as is the case in Cascade Tunnel, freight trains are slowed by an ascending grade. Usually passenger trains move fast enough to allow most of the exhaust heat to blow on by over the tops of the cabs. What was needed was a ventilation system which would prevent engine shutdown owing to hot air entering the cooling water radiators. Great Northern's Motive Power Department officials specified such a ventilating system and the designers came up with one. In order to install the new ventilating system the East Portal of Cascade Tunnel received a face-lifting, which included a steel drop-type door that completely sealed off the tunnel entrance, as well as a blower installation designed to move air through the tunnel from east to west. Two 800 h.p. electric motors drive 6-foot fans to do this. When an eastbound train enters the West Portal, moving upgrade, the East Portal door is closed and one fan is started. This sends a 220,000 cfm air blast against the locomotive (it can't escape through the East Portal because of the closed door). Obviously, there is plenty of air flow around the sides of the locomotive and the hot exhaust gases are blown back or cooled by the 220,000 cfm air flow. When the train is within about 3000 feet of the East Portal, the door automatically opens. When the train leaves the tunnel the door can be closed again and both fans can be cut in to blow the 8-mile bore clear. An interesting (and somewhat hazardous) problem cropped up as a result of "supercharging" the bore with air. When the door opened to allow eastbound trains to move out of the tunnel, a 100 mph gale dynamited out of the tunnel and rocks and debris were thrown in all directions. To minimize this hazard, the Great Northern blacktopped the area around the tunnel entrance and in so doing reduced the presence of stones and other objects to a minimum. In 1956, following the installation of the new ventilation system, freight diesels took over all operation through Cascade Tunnel. After nearly a half century of electrified operation, the wires were taken down. The Great Northern's Cascade Mountain electrification was at an end. What the electrics had done to the old Mallets a quarter-century before, the diesels did to the electrics. In 1956 the electric locomotives went into storage and subsequently were sold or scrapped. The 10 Class Z Westinghouse units were all scrapped sometime after the electrification was discontinued since a buyer could not be found for them. The Class Y General Electric units were quickly bought by the Pennsylvania Railroad. Seven units (5010 and 5012-5017 inclusive) were assigned to Pennsylvania Railroad Class FF-2 and carried the numbers 1 through 7, obviously the lowest numbers on the Pennsylvania Railroad. No. 5011, which had been damaged in a fire and had been rebuilt by the GN with a streamlined cab, was dismantled by the PRR for spare parts. Its streamlined cab was scrapped. The two GE Class W units which were built in 1947 were held in stor age at Wenatchee for some time. In ୮ 1958, the 5018 was sold to the Union Pacific for rebuilding to a coal-burning gas turbine-electric locomotive. In late 1959 the 5019 was sold to a Seattle scrap firm. The discontinuance of the Great Northern electrification is no reflection on the ability of the electric locomotive to move a ton-mile cheaper than any other mode of operation. It was a simple matter of economics. Every time a train stops to change motive power it costs money. The cheaper operation of the electric locomotives on only 73 miles of the 1900-mile line was not enough to counterbalance the cost of changing motive power twice. Had the GN been electrified from Wenatchee all the way through to Seattle, the story might have been different and a single motive power change at Wenatchee might have been economically feasible. As has ever been the history of railroading, new power brings changes in operation, and the GN's Motive Power Department was quick to analyze what the diesels could do. The 1500 h.p. freight units were checked out at 570 tons per unit and the more powerful 1750 h.p. units (which have more traction motor capacity) at 680 tons per unit. From there it was only a question of what combination of units would provide the best operating characteristics. Ten 1750 h.p. units would be theoretically rated at 6800 tons, but Big G has found that with five on the head end and five more buried about 40 per cent back in the train, 125-car trains which average out at about 6400 tons can be handled at 14.5 mph on the hard drag up the 2.2 per cent grade from Skykomish to the West Portal. Ten 1500 h.p. units can make the same speed with 5700 tons. In the tunnel on the somewhat easier 1.6 per cent grade, the speed of such a train would climb to somewhat better than 19 mph, but the Great Northern restricts it to 17 mph to ease the pressure on the East Portal door caused by the train's piston effect. An interesting sidelight on the movement through the tunnel is this: Big G's Motive Power Department has found that a train operates at about 10 per cent lower speed in the tunnel than it would on a corresponding 1.6 per cent grade in the open air. This could be attributable to either the increase in resistance to motion caused by the train moving through the tunnel against the closed East Portal door (increase in the air resistance), or the lowering, by the previously mentioned heated air (by diesel exhaust gases), of the horsepower of the locomotive's diesel engines, or perhaps by both. And so the diesels came to the mountain, not the mountain of Jim Hill's day to be sure, but quite a mountain nonetheless. Eastbound crews must still move up 13 miles of 2.2 per cent grade from Skykomish before reaching the West Portal of the tunnel, and westbound trains see 7 miles of the same before they reach the East Portal. Great Northern still has a fair bit of hill climbing to do in the Cascades. But with 21 million pounds on drivers and 500,000 pounds of continuous tractive effort, 10 diesel units do not have quite as much trouble with the 2.2 per cent grade as the little old Rogers Mogul with its 20,000 pounds tractive effort had with the 4 per cent switchbacks Stevens Pass. over No question about it- Jim Hill, if he were here to watch a mile of freight cars moving up the grade behind the diesels at a good steady pace, would be satisfied, and SO would John Stevens. I | Pictorial treat for Camelback devotees... in January TRAINS |