March 8, igoa] 
FOREST AND STREAM. 
\ 9 3 
alone, In other words, speed would vary inversely as 
the weight, and time allowance should be directly as the 
weight, so that, for example, two tons carried a mile in 
two hours would be as meritorious a performance as one 
ron moved a mile in one hour. And for racing pur- 
poses these two finishes would be deemed a tie, the light- 
displacement yacht giving the heavy yacht one hour allow- 
ance* 
That is to say, Thalassa does not consider yacht 
races to be speed contests, but contests of speed efficiency 
in moving weights. 
To this, there are two answers : (a) This reasoning 
does not justify the retention of +L in the formula, but 
would seem to require its exclusion for, other dimen- 
sions (including sail) remaining the same, increase of 
L reduces speed by increase of skin friction due to added 
weight, which under this scheme is not to be taxed, but re- 
warded. 
(b) If by inserting — D in a measurement formula 
racing length were to be reduced in proportion to increase 
of resistance caused by added displacement and thereby a 
proportional time allowance given, then tug boats with 
tows, and merchant vessels with cargoes, could compete 
successfully in races with steam and sailing yachts, mak- 
ing up for loss of speed by amount of load carried. 
But in his discussion with Mr. Phillips (Forest and 
Stream, Jan. 18), Thalassa takes just the opposite posi- 
tion, and says : "Now, our rating rule is a measure of 
speed. * * * We no longer race with cart horses, but 
with thoroughbreds." This is inconsistent with his 
"weight driven at speed" measure of efficiency for racing 
yachts. 
Yacht races are presumed by the writer to be speed con- 
tests pure and simple, the test of excellence being speed 
alone. That this is also the view generally entertained 
by yachtsmen seems evident from the fact that in racing 
rules, credit has not usually been given for the amount 
of weight carried. 
In speed contests, prizes are given for speed alone and 
not for work efficiency. The load is reduced as much 
as possible, and all the available energy is used to pro- 
duce speed. The minimum load to be carried is, for 
expedient reasons, often fixed by rule. No one is obliged 
to carry more than this, and the contestants are thus put 
on even terms with respect to the weight carried. If 
any one waste his energy by carrying more, and lose 
speed thereby, it is his own fault, and is not to be re- 
warded. 
In yacht racing the separation of the yachts into classes, 
the taxation of any important element of size as S or 
L, the penalty of lost speed for excessive weight, and the 
natural limitations to light construction, tend to insure 
substantial uniformity in the load carried by competing 
yachts. But, if desirable, with a measurement formula 
containing S only, it is easy to fix a minimum displace- 
ment for each class. 
3 
If the factor, — 16 v D, in Thalassa' s proposed for- 
mula does not insure a time allowance that is sufficient 
to exactly compensate for loss of speed due to burden, 
then instead of being a logical measurement formula, it 
becomes what Thalassa pronounces a "pernicious shape 
rule." And in any case it is not a logical measure of 
speed. 
Whatever amount of D is deemed desirable in racing 
yachts may better be secured by a special regulation 
made for that purpose only, than by putting a factor — D 
into the measurement formula, thereby making cargo 
carrying, in some measure, equivalent to speed. Thalassa 
gives unqualified approval to restricted classes for local 
racing. It is not apparent why they are not equally suit- 
able for international races. They have been used with 
satisfaction in the Seawanhaka international cup races, 
and they would make the races for the America's Cup 
more interesting and instructive than the last two races, 
which have been largely contests in mechanical engi- 
neering. Sextant. 
Rematks on The New Rating Rule. 
My remarks on the rating . rules,' published in Forest 
and Stream of Nov. 30 last, were scarcely complete from 
the point of view of American yachtsmen, because no 
mention was made of the rule recently adopted by the 
racing association of yacht clubs on Long Island Sound. 
The omission was intentional and was mainly due to the 
writer's ignorance concerning the said rating rule now 
generally known as Mr. Hyslop's rule. Since November, 
however, the report of the Committee on Measurement, 
February, 1901 (published by the Seawanhaka Corinthian 
Y. C), has been received with a request to analyze the 
rule and write an article upon it; by no means an easy 
task, as the rule is extremely complicated. Any de- 
signer who has to build to the rule will probably agree in 
this. To half the waterline length is added half the 
square root of the sail area, and to this is added a term 
called L, an ill-advised nomenclature, because it has for 
so long been employed to signify length of hull on water- 
line, not only in America, but in all countries where yacht 
racing has been introduced as a sport. 
I shall, therefore, for the sake of clearness and sim- 
plicity, venture to express Mr. Hyslop's formula in its 
more rational terms, and avoid the employment of his 
very confusing "L." It then becomes: 
1.1 (Linear Rating) + % » ST + C + E, 
using his own letters C and E, although C is also a bad 
letter to employ, because it has hitherto been frequently 
used .'to represent the constant multiplier. 
There is no conceivable reason for introducing the frac- 
tional coefficients in connection with the two principal 
items of the formula, and inasmuch as the old Seawanhaka 
rule- used unity for these coefficients, it will be better to 
state the formula in that way. It then becomes : 
2.2(LR) = (L+fs) + 2(C + E), 
which collects the Seawanhaka old measurements and Mr. 
Hyslop's new taxes into two items — the first term, so to 
speak, comparing with the old Seawanhaka rule, wherein 
• ■ • 2 (LR) = L + 
■ 
is the ratio of 2 to 2.2, or of 10 to 11. Hence, in all . cases 
such as those of Lasca, Iroquois, Volunteer, Titania, 
Katrina. Minerva, Nymph, Kathleen, etc., where 
C4-E=0, their linear rating by Mr. Hyslop's rule would 
be only 10-nths of their, rating by the old Seawanhaka 
rule. Thus, Volunteer's old rating was 01.08, and 10-nths 
of this is 82.80, her new rating, 
Kathleen's old rating was 37.44, and 10— liths of this 
is 34.04, her new rating. And so on with the others. But 
the main point to investigate is the effect of the new rule 
on design. In other words, the evolution of new boats 
under the rule. 
It causes the waterline plane to be measured for beam 
in three places : 
B at one-eighth of L.W.L., fore end. 
B' at one-eighth of L.W.L., after end. 
B", greatest beam. 
Then C=B-KB' — B", with the proviso that C is only 
used as a positive quantity, and consequently this tax is 
in the nature of a limitation at a definite point, and any- 
thing of this kind is bad style for a rating rule which 
should never tend to limit design at any particular point. 
If it be advantageous to design yachts with a scow-like 
water plane, the formula tells the designer he may do so 
up to the limit of B+B'=B" without tax. This is like 
telling a man that baccy is bad for him, but he may 
have four pipes a day. 
It seems to me that if the Seawanhaka Y. C wish to 
tax the scow-like water plane in a mathematical and 
reasonable manner, it could be done far better by new 
measurements of L rather than of B. Thus, let 
L=(LWL-f-2l), one-third 1 being the length of waterline 
plane measured at one-quarter beam of waterline plane at 
the MSS (midship section) — or at the 0.6 LWL section 
adopted by the British Y. R. A. in preference to the MSS 
Then, the actual L used for rating would be the mean 
value between 2I and LWL, and the scow would be 
sufficiently hard hit, I think. Moreover, all scow-like 
forms would be proportionally taxed according to the 
amount of their scow-like tendency. In other words, it 
would, as it were, tend to make even one pipe of baccy 
distasteful to the inveterate smoker. 
Mr. Hyslop's second tax, E, is very much of the same 
nature as C. It is a limitation aimed at securing a fair 
amount of submerged area of MSS as compared with the 
area of the inclosing rectangle of (B") multiplied by 
CD) draft at that MSS, "plus two-fifths of any greater 
draft aft" (which is bad English, as I presume two-fifths 
of any excess of draft aft is really intended; "and all of 
any greater draft forward" by v which I presume all of any 
excess of draft forward is intended. The actual algebraic 
form of tax for E is any excess of B"-|-D over 33- ^M, 
M being the immersed area of MSS (midship section). 
Then, E = B -f D — J-fi V m" 
E only being used as a positive quantity, and therefore 
here again we find a limitation of something regarded as 
undesirable. 
From this point of view it would be better if the 
Hyslop rule were altered so that (C) and (E) might be 
used not only as positive, but as negative quantities. 
Instead of playing the tune on one octave, the whole 
gamut could then be usefully employed. 
The rule would remain unaltered in form, but the taxes 
(C) and (E) would be used as either positive or negative 
quantities as derived from the equations: 
C = B 4- B' — B 
E = B " + D -lp. 
But, just as I thought a revised method of measuring L 
would be preferable to the complication (C) ; so, I think, 
the simple measurement of (d) the depth of immersed hull 
of MSS at its quarter B (waterline) would be found quite 
as effective as the complex proviso marked (E) in Mr. 
Hyslop's rule. But before I proceed to elaborate this 
idea, a rather curious algebraic fact connected with Mr. 
Hyslop's rule should be noted. If the two equations for 
C and E be examined, B" is found in each, but positive 
in E, and negative in C, consequently when C and E 
are added together as they are in the rating formula, 
B" vanishes, and we find 
c 4- E = B 4- B' + D — IOl v'm. 
Hence, a designer may make maximum beam on water- 
line anything he likes (other taxable things remaining 
unchanged) without altering the rating. A flat surface, 
four nails, one pegged at each end of the LWL and one 
at each end of B and B', and a pliable batten will prove 
that they do not by any means fix the dimension B" which 
can be varied within certain limits quite easily — and — as 
the total displacement of the yacht should not increase 
with increase of B", the section would require reduction 
in immersed depth and its area might remain unaffected. 
In any case I think the Hyslop rule ' might be more 
conveniently stated if B" were unmentioned and the rest 
stated thus : 
Linear Rating = -LA (Seawanhaka 4- Hyslop's tax) 
and H = B + B' + D - .U> Vm 
but only used if positive. 
The measurement of (d) must be done when yacht is 
hauled up or beached, and both sides would require meas- 
urement, not only in order to check any discrepancy due 
to the yacht's hull being slightly out of plumb, but also 
because the two sides of a yacht bottom are not invariably 
exactly alike. The (d) in each side being found, and the 
mean value used as the true (d), the rule I would 
then suggest to employ, as having the same tendency as 
Mr. Hyslop's, but being far simpler for designers to work 
L VT - . . 
to, is: Linear rating = 5 — divided by a constant, 
say 15. Applying this rule to Minerva, as shown in Dixon 
Kemp's "Yacht Architecture" and to a small fast 
cruiser by Linton. Hope of 24 linear rating by the present 
Y. R. A. British rule (published in Yachtsman ..of May, 
1901 ) , we find : 
Linton Hope's 
1 (4m«r»x Cruiser. 
LWL 40-50 22.50 
1 at % beam ... 27.25 . 17.90 
27.25 17.90 
Divide by 3 95.00 J 58.30 
L 31.67 X9-43 
♦'"ST multiply 56.50 54 J 5 - 
D, divide 2.90 : oe 
Result 617.02 370.70 
Divide by 15 and linear rating 4 T -I4 
In the "illustration" showing the sections "chargeable" 
under the Hyslop rule, the centerboard is shown with its 
board hoisted. Of course, this would give centerboard boats 
a tremendous advantage under the E tax of the formula, if 
such tax were continuous into negative quantities, It 
may be that this is a reason for the non-continuity of the 
rule, and for its limitations. If continuous and with- 
out limitations, the section chargeable for centerboards 
would evidently in all fairness have to include the draft 
when board is dropped to full extent, and if this were 
done, the proviso as to the board's specific gravity and all 
restriction of the kind could be omitted. 
As one of your correspondents very truly pointed 
out quite recently, a rating rule should not require any 
additional restrictions. It should be automatic, and the 
type evolved from its action should be untrammeled by 
anything outside the rule. 
Speaking generally, the great defects of Mr. Hyslop's 
rule are the introduction of limitations, converting it into 
a restriction rule rather than a rating rule, but the 
tendency of the rule so far as one can foresee at present 
appears to be healthy, and it certainly compares favorably 
in this respect with the wretched production of the British 
Y. R. A. — a rating rule that destroys the- seaworthiness of 
all small yachts built to fit it. 
Poor little boats! 
It cuts off their keels with a Y. R. A. knife, 
"You never saw such a thing in your life," 
The Y. R. A. Council has caused all the strife; 
Poor little yachts ! 
Reverting to the rating rule which I have suggested, 
vjz. : "i 
It can, of course, be used in the plus and minus form, 
when it may be expressed thus: 
L R = L 4- V"s"_ iBd 
Linton Hope's 
Examples. Minerva. Cruiser. 
LWL 40.50 22.50 
2 1 54-50 35.8o 
hj- 31-67 19-43 
v S, add 56.50 24.180 
15 d, deduct 88.17 44.23 
43-50 
Linear rating 44.67 24.73 
A rough sketch of the waterline plane is given on 
Figs. 1 and 2, showing the positions of 1 and d. PQR 
is the central length of WL plane; RQ is 0.6 LWL meas- 
ured from the fore end R. 
-wr 
Both d and 1 should be measured on the port and on 
the starboard side, as the two sides of a yacht always 
differ a little, and sometimes a good deal, d can be 
found by using a heavy plumb line from W, and a square 
with its horizontal leg equal in length to OW. The meas- 
urement WX (Fig. 2) then gives d. This measurement, 
must be taken when the yacht is ashore, and standing as 
nearly upright as possible, d must be taken both on the 
port and starboard side, and the mean value adopted. 1 
can be found by using a square adjusted so that ZP=OQ 
or OW. Then ZV and ZU; similarly found at the fore 
end, added together and deducted from the LWL, will 
give 1, This measurement can be taken either afloat or 
ashore, the latter preferred, in which case the waterline 
must previously be carefully marked on the hull from 
P to and slightly beyond V, and from R to and slightly 
beyond U. 
No difficulty can possibly arise in making these meas- 
urements, d and 1, and no one can deny that the rating 
formula connected with them, whether the multiplying 
form or the plus and minus form be used, is far simpler 
than any of the rating rules now in vogue. I still 
think that a premium on displacement by a similar rating 
rule as I have already described in your columns Is 
superior to a premium on depth at quarter beam — but 
so few racing men like the idea of weighing their yachts 
for a rating rule [N. B. — the German Emperor is a 
brilliant exception, as H. I. M. has adopted the principle 
in connection with his small restricted classes for the 
coming season], that it seems necessary to bring to their 
notice the substitution of depth at quarter beam of MSS. 
The only fear is the possibility of such a rule again 
encouraging the type of narrow and deep hulls. But I 
remember the remark once made to me by one of our 
first designers, that he had no fear of the plank on edge 
type being again successfully employed as a racing yacht. 
If this be a correct view, as it probably is, the employ- 
ment of depth of immersed MSS at one-quarter beam may 
be employed in a rating formula without misgiving, and it 
