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gage in high pressure cylinder. Upon opening the exhaust at about eight- tenths of the stroke, I should 'then ex- pect the pressure to fall, say, to about 20 lb. on the low pressure gage, a heavy knocking action being experi- enced in the high pressure engine through the want of compression. And here I would now suggest that if we can link up the low pressure engine only, to do so and so force up the pressure in the low pressure valve box, this would also tend to equalize the 'horsepower. JI am presuming that the pump levers are driven by low pressure Should the levers be on the intermediate engine, I sug- gest that the imtermediate engine be run idle'in order to keep the pumps going. Should an intermediate shaft be broken or flawed, if theze is no spare one at hand, I suggest that it be changed, if possible, for the high pressure, putting the flawed journal forward; and here I would say at all times it is 'better to rob the high pressure engine for the low pressure, and go on as before compounding, than to exhaust from high pressure to low pressure, and so avoiding the stresses set up in 'the shafting by the unequal turning moment. Coming to the low pressure engine, in the case of any casualty happening here, it is more interesting still to see how we could meet the difficulty. First let us suppose 'that the slide valve is broken, then we shall have to exhaust from the intermediate pres- sure into the condenser, and if the levers are driven by the low pressure engine, drag the low pressure round idle in order to work the pumps. If the valve spindle or eccentric rods be broken, then, if possible, rob the high pressure engine and go on com- pound, or if the shaft should be flawed, change, if possible, forward, remembering that the low pressure shaft has to transmit the horsepower of the three engines, and, therefore, there is three times the stress in that shaft as in the high pressure shaft. I have an instance of a low pressure Piston rod being broken short off at the crosshead. The engineers set to work, and, drawing the slide valve, Temoved the broken rod and piston, blocking the steam ports, and drag- ging round the connecting rod with their crosshead attached, worked their Pumps, thus keeping their engine a Surface condensing engine. I cannot impress too much upon you that at all times, with modern marine engines of high pressures, it is better to keep _ the condenser surface condensing, and SO obtain fresh water for the boilers, engine. "TAE. MARINE. REVIEW sacrificing anything in the shape of vacuum, etc., to obtain it; and I think it would not be out of place here to recount an actual breakdown that oc- curred to a large vessel bound for the colonies. Falling into bad weather, the engine raced heavily for some two or three days, and eventually one of the top end bolts gave way, and the engine, so. to speak, took a long stroke, or, in other words, the piston and piston rod left the connecting rod, striking the cover and fracturing 'it, splitting the cylinder, breaking the caps of the rocking shaft of the levers, doubling up the levers and generally smashing up the pumps. Here their salvation lay in having a separate in- dependent circulating pump. The first thing they did was to lift the low pressure valve box cover and exhaust from the intermediate pressure into the atmosphere, putting cold sea wa- ter into the boiler, while patching the deduction pipe. As soon as they could exhaust into the condenser they did so, and by cutting a 4-in. hole in the bottom of the condenser and connect- ing the independent feed pump to it they managed to obtain fresh water for their 'boilers. On 'the passage home, they worked high and inter- mediate on 'to the 'condenser and dragged the low pressure connecting rod round with crosshead attached to work their levers and pumps, doing without the low pressure engine. They obtained fairly good results upon the passage home. I would also tell you of how a knowledge of the early history of the engine came to the aid of engineers in a serious breakdown in an ordin- ary tramp steamer homeward bound across the bay in fine weather but with a heavy rolling sea. The boats had been cast adrift from their lash- ings in order to give them a coat of paint, when by some means the man at the wheel allowed the ship to fall off into the trough of the sea, and a big sea coming on board amid- ships lifted one of the boats and dropped it on to the skylights, which were of the old-fashioned wooden type. The skylights gave way, and the result of the accident was a broken low pressure cylinder cover. The engineer, having a knowledge of how Watt first moved in the devel- opment of the engine, determined to try and work the low pressure en- gine as an atmospheric engine. First they removed the broken cover, and, blocking the top steam port to pre- yent a loss of vacuum on the up- 'stroke, they then cut off the bottom lap of the valve; and, putting the ec- 43 centric back till nearly at right an- gles to the crank, they set her away, carrying steam the whole length of: the up stroke, exhausting at the end of the stroke into the condenser, the work of the downstroke being accom- plished by the atmosphere. I should now like to bring before your no- tice several cases of how shafting has been repaired by engineers at sea with little or no tools at their command or material to work with. In the first case great fertility of resource was shown, the shaft being fractured across the web. It was a built shaft, the sides of the web be- -- ing parallel and the ends rounded, the fracture appearing straight across the web. The engineer casting about for something to make a strap with suddenly hit upon the novel expedi-. ent of removing .a. stay. from the steam space of one of his single-ended boilers and bending it round the web. He then. cut a plate out of one. of his flooring plates, and putting three thicknesses of this plate across the web, firmly bolted it together, heat- ing the strap up to a bright red be- fore tightening up the nuts. Here you see he had already the ends screwed and nuts to fit, going to slow with reduced pressure. The second case is where a- short' inter- mediate length of tunnel shafting | fractured abaft the coupling, the fracture extending for 15 in. fore and aft. The diameter of the shaft was 12% in, with eight 2%4-in. coupling bolts in each coupling. Fortunately, it was fitted with a stern way collar against the aft main bearing in the tunnel, which prevented the shaft from running aft. The engineers first thoughts were to sink three keys into the shaft and endeavor to make clips to go round them afterwards; but he abandoned this idea in favor of the following method of splicing the shaft. He first removed the bearing to the forward side of 'the coupling, pack- ing it up with logs of wood and shoring it from each side of the tun- nel. Removing four coupling bolts .from each coupling, he then utilized the steel towing or mooring hawser in the following manner: Passing the -- hawser, after belaying it on the for- ward side of the coupling, fore and aft through the holes he had re- moved the bolts from, until he had five ply of the hawser through each hole, giving them 20 ply in all, to take up the torsion, then strapping round the shaft till made up solid with the couplings, he informed the captain he would not risk reversing the engine, but went away ahead, gradually