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THE BEST ARRANGEMENT FOR COMBINED RECIPROCAT- 
ING AND TURBINE ENGINES ON STEAMSHIPS. 
By G. W. Dickie, Esq., MemMBER oF CouNCcIL. 
[Read at the eighteenth general meeting of the Society of Naval Architects and Marine Engineers, held in 
New York, November 16 and 17, 1911.] 
It is by invitation of the Committee on Papers that I am presenting 
to the Society what I think should be the best arrangement of combined 
reciprocating and turbine engines on steamships. In accepting this invita- 
tion, I am well aware that the opinion I have reached, after much thought 
on the subject, is at variance not only with the opinion but also with the 
practice of some very eminent engineers, whose experience is much wider 
than mine. It is to be expected, therefore, that what I have to present will 
be challenged and declared entirely untenable. If I thought the members 
of this Society would agree with me in regard to anything I might present 
before them, I would not take the trouble to present this paper. I amstill 
Scotch enough to enjoy discussion and criticism, especially when admin- 
istered with the good feeling that prevails in this Society. 
While the subject of this paper is “The best arrangement of combined 
reciprocating and turbine engines on steamships,” it does not follow that the 
arrangement proposed by the author is the best. The Committee on Papers, 
I presume, would like to have the question discussed and it is quite possible 
that the presentation of the very worst arrangement may enable the Society 
to discover the best. 
Among the many benefits to steam engineering, that have resulted 
from the introduction of the modern forms of the steam turbine as a rival 
of the highest developed type of reciprocating engine, none is of more im- 
portance than the wider knowledge among engineers, that has come with 
the rapid introduction of the steam turbine giving rise to conditions that 
must be met and satisfied by the reciprocating engine that is to use steam 
economically. Experience with the turbine has emphasized, not only the 
weak points of the reciprocating engine, but at the same time furnished like 
evidence of its own weak points. 
It so happens that both types of steam engine have an economical and 
a wastefulend. In the turbine the steam begins its work in the wasteful end 
and finishes in the economical end, while in the reciprocating engine this is 
reversed. ‘This condition, in the reciprocating engine, is largely due to 
functional causes. The alternate heating and cooling of the cylinders, 
caused by the drop in temperature as the steam expands and produces work— 
the difference in temperature being much greater in the low pressure than 
inthe high pressure end—and the consequent condensation due to the heatab- 
