130 RULES AND REGULATIONS FOR FREEBOARD. 
The proposed standard of longitudinal strength is measured by the modulus 
of resistance of the midship section of the vessel computed by the usual methods. 
The standard = is found from the formula— 
It 
yulxoxd, 
where 6 is the breadth of the vessel, d the extreme summer draught and f is a 
longitudinal strength factor tabulated in terms of the vessel’s length. The = 
through a section in way of the midship deck openings must not be less than 
.9 Xf X 6 X d, so that provision is made for a definite standard of deck compen- 
sation abreast openings. Straight line formulae are given for determining the 
standard minimum thickness of side plating and the corresponding frame spacing for 
any length of vessel, together with a method for estimating the increase in shell 
thickness required for variations in frame spacing over the standard. As transverse 
strength is at least of equal importance to longitudinal strength, it is gratifying to 
note that an endeavor has been made to lay down a minimum standard of strength 
for at least one of the transverse members of the hull structure, z. e., for hold framing, 
and that the proposed formula for the required 4 of the frame section takes account 
in some degree of the principal factors which should enter into the determination 
of the frame scantlings, 7. e., length of unsupported frames, spacing of frames, 
load draught and height of deck loads. 
While the proposed standard of strength is probably satisfactory enough as 
far as it goes, it is anything but complete, as a ship could be designed to comply 
with the new standard and yet prove very unsatisfactory from a structural point 
of view. Provided its limitations are understood, the proposed standard of strength 
should prove distinctly useful to naval architects, but it cannot take the place of 
classification society rules, as nothing is said about riveting and such important 
considerations as the bottom framing and the thickness of deck plating in relation 
to beam spacing. While the size of the frames as derived from the standard is 
affected by the height of the bracket floors, the size of the beam knees at the lowest 
tier of beams is not taken into account in determining the modulus of resistance 
required, and although the necessity of providing sufficient stiffness in the frame 
apart from the 4 value is emphasized, the necessary modifications to scantlings 
on this account are left to the assigning authorities. As the strength standards 
laid down are for vessels built on the ordinary transverse system, their application 
to longitudinally framed ships will also necessarily be left to the assigning author- 
ities. No reference is made in the report to wooden or composite vessels, and this 
omission may have to be remedied in any international rules in view of the con- 
siderable amount of wooden tonnage still in existence. 
The proposals of the 1913-15 Load Line Committee undoubtedly represent a 
