2 ON THE MAXIMUM DIMENSIONS OF SHIPS. 
In endeavoring to answer that question some persons resort to simple 
graphic methods. Dates of construction are used as abscisse, and lengths 
(or tonnages) of ships employed as ordinates. On these data curves havebeen 
constructed, whose production, in a tentative fashion, is expected to furnish 
some indication of what will probably be the dimensions of the largest 
ships say twenty or thirty years hence. Personally I have no great confi- 
dence in this method. It has no scientific basis, it rests upon an assumption 
that materials and methods of construction, as well as systems of propulsion 
will remain practically unaltered during the period under consideration; 
and it presumes that the law of growth will hold continuously. It may be 
replied by those who favor the method, that it has answered fairly well so 
far; and that therefore it may be further employed with advantage. In my 
judgment, it is necessary to take a broader and more scientific view of the 
problem if a reasonably approximate solution is to be found. The means 
ought not to be altogether lacking for reaching a fairly approximate solution, 
if the conditions of the past and the outlook for the future are carefully 
considered. The case is not one for treatment by simple “rule of thumb” 
or more or less arbitrary extension of curves such as have been described; 
it requires an application of scientific analysis to past experience, and when 
this has been done the forecast based upon such analysis must necessarily be 
open to question, and may be falsified by subsequent events. In these 
circumstances caution is necessary and differences of opinion are justifiable. 
Probably the most useful procedure will be to make a detailed statement 
of facts and principles which will, for the most part, command general 
assent; and in doing so it may not be out of place for me to state my own con- 
clusions on points of controversy. 
I. It will be agreed that the law of growth in dimensions has operated 
hitherto on all classes of ships and that its action has on the whole been 
beneficial. Members of this Society treat as axiomatic the statement that 
economy in propulsion and over-sea transport has been and always will be 
promoted by increased dimensions. The actual influence of such an increase 
has, in many cases, been masked or made less obvious byconcurrent changes 
in other factors and features of ship-construction, but it has been none the 
less felt. Stronger materials of construction have been made available; 
more efficient types of machinery and propellers have been devised; higher 
steam-pressures have led to greater fuel economy, and higher rates of revolu- 
tion have favored relatively lighter propelling apparatus. But after each 
such improvement has been introduced and utilized, the law of growth in 
dimensions has inevitably reasserted its claims on naval architects, and been 
again brought into operation in order to secure still further advantage in 
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