24 



ON TUB METHOD ADOPTED TO COMPOUND 



Very well, then, to sum up the conditions upon wliicli this 

 vessel entered on her second commission in 1875: — 



Two cylinders, 66 inolios diameter x 72 inches strolcc, as before. 



Working pressure, 30 lbs., as before. 



New surface condenser, with 4,7.54 scj. feet of cooling .surface, in- 

 stead of the old jet condenser. 



Now Ifi-inoh centrifugal pumping engine. 



Four boilers, with 14 furnaces instead of IG as before. 



Paddle wheels, the same us before. 



The draft of water, displacement, midship area, remaining the 

 same as before. 



The result was that pi'actically the same horse power was 

 developed, the same speed was maintained, and the con- 

 sumption was reduced to 84| tons per voyage, equal to a 

 saving of 81 percent. As I have stated before, the saving 

 expected was 12 per cent., but it appeared that this was too 

 sanguine a view, and economy on the lower scale was not 

 despised, as it -meant close on 400 tons on the year's worlc- 

 ing. Very well, then, she went on saving 400 tons a year 

 until this second set of boilers was worn out, in 1885. 



And now I come more particularly to the subject matter 

 of my paper. 



In the interval I need scarcely remind you that competi- 

 tion had become much keener, and that this vessel had to 

 compete with others in the same trade more recently built, 

 and fitted with compound machinery ; and it was peiT'foctly 

 evident that she would bo out of tho race unless a consider- 

 able reduction could be made in tho coal bill. The vessel 

 was too good and too great a favourite to bo cast aside as 

 obsolete, and the cost of new compound machinery would 

 have been such that so great an outlay would certainly not 

 have been justifiable. There was nothing left for it but to 

 compound the existing engines in the best manner possible, 

 providing this could bo done at modei'ato cost, and at tho 



