March 5, 1904.] 
FOREST AND STREAM. 
FAST CRUISING LAUNCH, 39 FT. L.W.L. DESIGNED BY LILJEGREN & CLARK. 
The Cyiinder. 
We now come to the cylinder. On this subject there is 
very little to say, except that care should be taken to 
ascertain before buying an engine whether the builder is 
equipped to furnish a cylinder that has been reamed. 
I'he reason for this is that very few cylindersn after be- 
ing bored, are of the same diameter at both ends. This 
is owing to lost motion in the boring bar when extended 
through the cylinder. A properly equipped manufacturer, 
after boring the cylinder, will run a reamer through, tak- 
ing out but a few thousands of an inch, but just enough- 
to make the cylinder perfectly true from end to end. The 
writer has seen a number of cylinders that have' beer, 
smoothed up by inserting emery and oil and allowing the 
piston to grind itself in with the engine belted up. This 
of course makes the cylinder appear perfectly smooth, but 
does by no means correct the aforesaid evil. While 
speaking of the cylinder, we would mention what is called 
the compression space, or the clearance between the top 
of the piston when at its upper center and the cylinder 
head. This space varies somewhat with different makes 
of engines, but a good, safe rule, and one almost univer- 
sally adopted by the best designers, is to allow one-third 
of the area of the cylinder. Of course it is obvious that 
by reducing this space the compression will be higher, 
therefore, theoretically, more power. To offset, however, 
this extra compression, we should have to add weight to 
the flywheel, and of course the heavier the flywheel the 
more power it requires to preserve its momentum. 
Again, if we reduce the compression space beyond a cer- 
tain point, we are reducing the volume of gas which we 
have to ignite, and although we may by high compres- 
sion and small compression space obtain a very high ini- 
tial pressure, there will be insufficient gas to obtain the 
necessary expansion throughout the stroke. 
Another point which is an objection to high com.pres- 
sion, is that it requires much greater cooling surface, 
consequently more water, and it is very liable to produce 
over-heating of the electrode point and other projections, 
and cause the engine to ignite spontaneously. While on 
this subject, we will mention a cause of trouble in some 
engines that we have seen, this being lack of material 
in the bar across the inlet and across the ports in the cyl- 
inder; this bar is put there to prevent the rings from 
slipping into the ports, and where these bars or bridges 
are not sufficiently rigid, the boring tool will jump on, 
siriking them and leaving what we call a high spot in the 
cylinder. It might be thought that reaming the cylinder 
v/ould obviate this, but in many cases these bars are so 
light that they will be sprung outward by the reamer, 
which consequently does not cut them at all. 
[to be continued.] 
The Erie Basin Y. C, of South Brooklyn, received its 
certificate of incorporation on February 25. The officers 
of the club are: Com., W. E. Wise; Vice-Com., C. W. 
Cooper; Rear- Com., E. Harrington; Sec'y, G. Buass; 
Treas., Thomas F. Patterson, M.D. ; Meas., C. Maher ; 
Trustees — Martin Flanigan, G. Gutkes, and H. Krause. 
The club will build a club house on property adjoining 
the yards ofj the John N. Robbins Company. 
" ' m 9t m ' 
Mr. Charles L. F. Robinson, N. Y. Y. C, will sail on 
the schooner Ingomar on the other side, and will act as 
Mr. Plant's representative.. ■ _ . ■ 
Ingomar will be able to compete in the race for Heligo- 
land cup offered by the German Emperor. Hitherto only 
British and German yachts were eligible to race, but now 
it is open to yachts' of all nations. 
The annual meeting of the Huguenot Y. G. was held at 
the 'Arena, West' Thirty-first street. New York city, on 
the. evening of February' 27, and the following officers 
were elected: Com., Georjge C. Allen; Vice-Com., L.- C, 
Ketchuni; Rear-Com., 'Qearge- G. Bell ; "Sec'y, William jB.- 
Greelfey; snd .Treks.'r jdhU .'S. -Taylor. W:- L. Searles .and 
H'eriry de" f: Bardwln'^^^et^ |iitet§?i, trustees- to^ serve for- 
\W0 years. ' ' ■ ' ; ' ' _ 
Fast Cf wising: Launch. 
The accompanying design by Messrs. Liljegreu & 
Clark, New York city, and now in course of construction 
at Goteberg, Sweden, suggests a successful combination 
cf speed, comfortable accommodation, and seawdrthiness 
within the given dimensions. 
■„The design- shows good freeboard, which is one of the 
essential features, giving headroom with a low cabin 
■Mouse, , and adding to the general seaworthiness of the 
'boat. j 
The adoption of the twin screws reduces the liability of 
several hours' drifting about, a possibility tO' be con- 
sidered in cruising launches. The dimensions are as fol- 
lows : L.O.A., 39ft. 6in. ; L.W.L., 39ft. ; beam, 6ft. 7in. ; 
draft, ift. Sin. ; freeboard forward, 3ft. 4in. The guar- 
anteed speed is 18 miles per hour. 
Measurement of Racing Yachts. 
EiUtor Forest and Stream: 
I have read with great interest the various letters which 
have appeared in your journal in answer to my article on 
"Notes on the Measurement of Racing Yachts." The 
paper in question was not intended as a complete exposi- 
tion on the subject of measurement rules; nor was it 
intended to advocate my particular rule or method of 
measurement. The purpose and limitations of the paper 
vv'ere clearly stated in the opening paragraphs as "to bring 
clearly before all yachtsmen the fact that the present 
rules of measurement are founded upon certain assump- 
tions as regards the speed of yachts; to show that such 
assumptions are not clearly warranted by the data at their 
command." From reading the many letters, I believe that 
my paper accomplished the stated purpose. 
The comments on my paper can be divided into two 
classes ; comments on what my paper contained, and 
criticisms of omissions. The latter class I cannot attempt 
to answer, for I am well aware that many vital poinis 
were not touched upon in my notes — points that I should 
certainly have taken up had I been advocating any special 
rule or any method of measuring or rating yachts. 
Should one attempt to discuss all the points raised in 
the many letters, one would be obliged to write a treatise 
on yacht designing and yacht measurement. 
My paper was devoted to an attempt to bring out 
clearly two points, and two points only: ' 
First — That the present measurement rules involve cer- 
tain assumptions, and that these assumptions are that 
the speed of a yacht is proportional to, 
a. The square root of length of hull, 
b. The fourth root of sail area, 
and that the New York rule involves these two assump- 
tions and the additional one that speed is proportional 
to ■ 
c. The inverse sixth root of displacement. 
Second — That these three assumptions are not clearly 
warranted by the data at the command of every yachts- 
man, and that if further investigation should prove the 
assumptions unwarranted, then all the present rules are 
wrong, and no amount of doctoring will correct them. 
There has been no criticism of the first point; therefore 
1 may assume that all the writers agree with me, and 
that I am correct in my statement that the present rules 
do involve the assumptions named. 
There has been criticism of the second point that these- 
assumptions are not clearly warranted by the' data. ; Some 
writers discuss one ■ assumption, some another, and per- 
haps the easier way to answer the , writers will be . to 
answer the criticisms -of my points rather than the indi- 
vidual writers. ■ 
: a. Assumption as . to length. ■ 
Very, few of the 'writers have touched 'on this point.; 
I said all I could; in favor of the. assumption, and, as 1. 
thought, stated guardedly and carefully that under cer- 
tain conditions and ' forjcertain speeds this assumption ' is: 
not radically wrong. TJiis point has- been ably discussed 
by Sextant, who haA explained very, fully the qtfalificatipns 
which niust Ofc.-necegsity-be applied to tliis - assumption. 
Length certainly does' not "produce" speed, as Sextant 
justly states,' but length of hull do€s affect the speed the 
"power" is capable 'of producing, and, Sextant to the con- 
trary notwithstandifig/'length may properly be brought 
. into an expression which measures the speed of a yacht. 
So, too, may beam, draft, displacement, dirtiensions of 
sails, length and size of rigging, and hundreds of other 
dimensions and minute peculiarities of the yacht. In 
fact, the speed a yacht is capable of making under certain 
average conditions of wind and water may be expressed 
' S = F.(.l, b, SA, D, etc.), ; 
into which can be introduced as many elements as one 
wants. This merely expresses the fact that speed; depends 
upon or is a function of, length, beam, sail area, -displace- 
ment, etc. What power or root of length should be in- 
troduced into the formula is a matter for investigation 
and experiment. But it is not impossible to find -a 
formula as a measure of speed which involves leiigth' and 
any other dimension of hull or rigging. It may not be 
vnse to do, but mathematically it is perfectly proper to 
do so. I do not mean to say that the manner in which 
length is introduced into the present rules is correct, but 
I do say that in a properly constructed formula it would 
be correct to introduce length and as many other factors 
as found advisable. 
Sextant's discussion of the point seems to leave us 
Vrf'hei-e I began, "the assumption is not clearly warranted." 
Possibly I erred in giving the benefit of the doubt to this 
time-honored assumption. 
h. Assumption as to sail area. 
I do not think that the discussion has brought out any 
points to change my general conclusion that the assump- 
tion that the speed of a given hull varies as the fourth 
root of sail area is not clearly warranted by the data. 
The best discussion of the point seems to be that of Mr. 
Maybee, who shows that in order to increase the sail 
carrying power, the form of hull must be changed, and 
who states "that the change of form almost invariably 
detracts from the theoretical advantage due to her in- 
creased propelling power." This may be correct when 
such wide divergences of type and sail carrying power 
are contrasted as the old and new Cup defenders. But 
with all due respect to Mr. Maybee, his first illustration 
is a case of false reasoning, as he begs the question in 
his premises. If, in the old-fashioned lead mines which 
he uses to demonstrate his point, the VSA equals L.W.L.-' 
then to a certainty must VSA equal VL, and , therefore 
4 
the VSA will be as good a measure of the speed of the 
boats as is VL; for these measures, by Mr. 'Maybee's 
premises, are identical. ' 
Mr. Phillips' statement in regard to Reliance would not 
need an answer, had not Mr. Lawton apparently given 
these statements the weight of his approval. In no part 
of my paper did I state or intimate that the speeds of 
different hulls are proportional to the square root or to 
any root of the sail area.; I did attempt to show the 
effect of sail area upon the speed of the same hull. Mr. 
Phillips would have been correct had he stated that "ac- 
cording to the theory advanced by Dr. Poor, we might 
expect . 'M' to show- an average speed of 1^.78 miles/' 
provided she could carry the same amount of sail as the 
Reliance actually did. Similarly, and with equal justice, 
we might expect the Arrow to rival in speed the fastest 
express train, provided she carried the engines of the 
Lucania. But Arrow cannot, carry the engines*and "M" 
cannot carry the sail. . Just as absurd conclusions can 
be deduced from the measurement rules in force ; the old 
New York rule, which makes speed proportional to the 
fourth root of sail area, and under which the Cup races 
were held, states that Reliance without any sail should 
make 6.7 miles, per hour ! The practical formulse are few 
from which ^ome absurd conclusion may not.be drawn, by 
applying, them to: -exaggerated- and impossible conditions. 
Cerfajii o| the writers criticise m_y method oK showing 
thatitKei^ai|ifnipi|6^^^ regard to lail area is n|t clearly, - 
wafraritedj'-'atid eipeeiaI;ly*'OTy example' .of 'the -two b6at8,' ' 
"E" . an4 , "M*"- /^"rifssp " writers ' failed ^td recogftize X^t 
