The salient feature of the reports of the board's officers on this
subject is the consensus of opinion that the form of a boat is the chief
factor to be considered in determining its value as a life-saving
appliance.
It has been found that while there are many boats of good form supplied
to ships, there is yet a large proportion where the boats are not only
not so good, but which can only be regarded as unsafe if they had on
board anything approaching the number of persons for which they measure.
It is the latter type we are chiefly concerned with; how is it that the
form has so deteriorated as to create this concern in our minds? I think
the cause is not far to seek; it appears to be the outcome of (1) the
shipowner's desire to carry the maximum number of persons in the minimum
number of boats; (2) in the efforts of the ship-builder, as a rule, to
carry out the specification in which he has contracted to supply the
owners with boats at a price, often very low, and naturally he does not
sublet his contract with the boatbuilder at a loss; (3) the aim of the
competing boatbuilder, which is to build his boats at as little cost
price as possible, and yet to provide accommodation for the prescribed
number of persons. He is probably limited as to length, and therefore
relies on the breadth and depth; in this direction, he is
unintentionally assisted by the board's rule for measurement, viz, L × B
× D × .6/10 or 8; so long, therefore, as he can obtain his breadth at
one point for measurement purposes, it is quite immaterial to him how
soon he fines away to the ends, with the result that the stability of
the boat becomes almost entirely dependent upon the form of a very
limited midship section, or the still smaller proportion of same that
would be under water when in the loaded condition.
The boatbuilder may be further restricted as to breadth, and, therefore,
he again detracts from the form a boat should have by dispensing with
sheer and increasing the depth from keel to gunwale amidships. This
method of building boats enables him to obtain the capacity required by
the owner at the expense of the boat's stability and utility.
No doubt when the life-saving appliances rules came into being the
divisors 10 and 8 for the different sections were deemed safe on the
supposition that the usual full form of boat would not be largely
departed from. Experience has shown, however, that form is frequently
sacrificed for the unworthy objects referred to above, and it follows,
therefore, that either the form should be improved or a heavier divisor
laid down.
It would, I think, be more effective to deal with form and devise a rule
by which we can insure that a boat will be reasonably safe with its
load, not merely in smooth water, as in our recent test, but in a
seaway. It is essential, therefore, to draw the attention of the
advisory committee to the value the board attach to form, and
particularly to that part of it under water, emphasizing the great
necessity there is for an increase to the bearing surface of the
under-water portion of boats, and this end can, no doubt, be best
attained by the putting into practice of the suggestions made by the
principal ship surveyor for amending the rules and which aim at
prolonging the form or fullness of dimension of the midship body under
water well toward the ends of the boat. It is well known that by
extending the body in this way greater buoyancy and stability are
secured without materially affecting the speed. It is often supposed
that defective stability due to bad form can be rectified by the
disposition of the persons or things, but anyone with real experience of
boats in a seaway can not fail to realize that this is the wrong
principle to work on. Granted, therefore, that the question of form must
take priority, how can it be best attained? And if we refer to Mr.
Archer's method of measurement, as stated in his amendment to the rules,
it will be seen how simple and effective it is. For the purpose of
illustration, we might take the model of a ship's boat obtained through
the board's surveyors at Glasgow, the dimensions of which enlarged to
scale represent a boat of L B D/30.0 × 8.5 × 3.5 and is an embodiment of
the proportions amidships and at quarter distance from each end proposed
by Mr. Archer.
It can not be too strongly urged that for a ship's lifeboat to be fit to
carry the number of persons it measures for in any degree of safety,
whenever it may be required at sea, the under-water or bearing surface
should be carried out to the ends as much as possible and all straight
lines avoided. The bows of many of the existing types of boat are
examples of the worst possible form for safety, and the counters are as
bad, if they can be said to have any.
_Depth._--It appears from the reports that the most generally approved
ratio of depth to the breadth is 4/10. This has been established not
only by our long experience, but by the numerous tests recently
conducted by the board's surveyors at various ports, and the attention
of the advisory committee might be drawn to this fact.
It is, of course, necessary also to have a good freeboard, but a
well-proportioned boat does not require so much freeboard as the
commoner type, as with proper sheer and under-water surface she is easy
in a seaway. If the gunwale is too high, there is loss of power over
the oars, which is serious when for the safety of the boat she is
required to be kept head-on to sea, and with a fresh breeze, even in a
good boat, this is not always an easy matter.
It is a matter for consideration that at the tests made by our surveyors
the conditions were most favorable, being usually in smooth water of a
sheltered dock, and, in not a few instances, considerable anxiety was
felt for the safety of those on board when crowded in accordance to the
existing rules. If it was thus in smooth water, one dare hardly
contemplate the results in a seaway. If the shipowner does not see to it
that a safe type of boat is provided, then the number of persons to be
accommodated in boats which do not come up to the proportions deemed
safe by the board of trade should be very considerably curtailed.