1^8 
FOREST AND STREAM, 
[Fes. 25, 1899. 
tematically; but rivalry among themselves appears to be 
quite dormant, and only shows signs of life during the 
festive cruise of the New York Y. C. down Long Island 
Sound in August. 
"Of course this is very dehghtful j'achting, and the 
stay at New Bedford. New London and Newoort is al- 
ways pleasant. Then comes the sail through "Hmn- 
phrey's Hole" to Martha's Vineyard, and on to Edgar 
Town, one of the primitive English settlements, and 
now the home of the codfishing men and some pilots. 
The serenity and neatness of the pretty little seaside village 
is beyond comparison, and perhaps this is enhanced by 
the infrequency of posts and ihe absence of morning and 
evening rewspapers. It is' quite an old-world place, and 
any Englishman visiting America in a yacht should see 
it; also Martha's Vineyard if in the August-September 
season, when the "prayer meetings are raging there. Of 
course, the passage up the Fall River is equalh' interest- 
ing, especially on account of its associations with the 
early English settlers- on the east coast." 
comparing different drawings, and in studying the many 
designs now available through the different yachting 
books and journals. Even if the correct scale is given on 
the drawing, which is not always the case, it may be 
desired to compare the drawing with another by means 
of a different scale; for instance, any good design of a 
2ift. yacht can, by means of the proper scale, be converted 
into a 25-footer, For all such uses the paper scales are 
Yacht Designing.-XXIV. 
BY W. P. STEPHENS. 
{Continued Jrom jage 11=*, Feb, W.) 
The illustrations accompanying this article are copyrighted by 
the Keuffel & Esser Co., New York, to whom we are indebted 
for their use. . 
The cardboard scales are necessarily flat, but scales of 
wood, ivory or metal are of three forms, Fig. 56, a, flat 
with single bevel ; b, flat wath double bevel, and c, triangu- 
lar. The first has one flat side next the paper, with each 
of the upper corners cut away on a sharn bevel and 
divided, the two graduated edges thus giving two or some- 
times four different scales. 
The second shape has a double bevel to each edge, giv- 
ing four surfaces for graduation. This form of scale is 
very inconvenient in use, as it never lies flat on the paper, 
Fig. 60 — Semi-circular Protractor. 
quite accurate enough, and a good assortment of them 
is desirable; but for original work some wood scales of 
the usual divisions, lin., ^in., J4in., etc., are to be pre- 
ferred. 
The diagonal method of division is very convenient m 
making a plain scale on a drawing, or in laying down any 
new scale. A line is drawn and divided into a certam 
number of equal parts ; for instance, if a scale of >4in. to 
the foot is desired, the line may be divided mto twenty- 
one parts, each VM.. as A, B, Fig. 57- From each pomt 
of division a perpendicular is now dropped, or in other 
words, a line is drawn at right angles to the first line. 
A series of ten lines, equidistant, and parallel to the first 
line, are now drawn. One of the end divisions is now 
subdivided into ten equal parts on the upper and lower 
of the parallel lines, each point bemg numbered as in the 
lO 9 9 7 6 
e 
A 
6 
A 
Fig. 57— Diagonal scale; deciinal divisions. 
7 g 5 A g a_ 
Fig. 58— Diagonal scale; duodecimal and eights. 
1 53456780 
1 
I 2,345 6789 
o ^ 
Fig. 59— V ernier scale. 
but must be held by one hand at a certain angle; it 
answers very well for a scale to be carried m the pocket, 
but it has no proper place in the drafting room. 
The triangular scale has the advantage of a large num- 
ber of surfaces for graduation, six in all on its three edges, 
and at the same time there is always one surface that lies 
flat on the paper while the particular scale in use at the 
time is held at an angle of 60 degrees, a very convenient 
one for reading and marking. Ihe standard triangular 
architect's scale has one edge divided into inches and 
sixteenths for its entire length, or divided to ^in. to the 
foot from left to right, and to %m. from right to left; one 
edge to y%m. and ^in. ; one to ^in. and im. ; one to 
r>-^in. and 3in., and one to 2 and 41".; or eleven different 
scales in all. . , • 1 
In working on any given drawing, there is a material 
saving of time in having the proper scale and no other 
at hand, so that it may be applied to the work as soon 
as it is picked up, without studying and turnmg to find 
the right scale on one of several edges. Except m the 
case of the cardboard scales, this is seldom done, how- 
ever, as it would call for a very large and costly collec- 
tion In this particular the single-bevel flat scales are 
ihe best of all, as there is but one side uppermost, and 
the required scale must be on one of its two edges. The 
triangular scale is the most inconvenient of all, as^ some 
one of the ten scales not wanted is sure to be m the 
place of the right one, and the scale must be constantly 
watched and turned. On the other hand, however, this 
form of scale has two distinct advantages, it contains -all 
rhe graduations in common use, and the face of the scale 
lies at a convenient angle, while the edge is brought much 
closer to the paper than in the flat scale. In the im- 
proved form of "triangular scale, the angle of each pair 
of edo-es is made a little less than 60 degrees, so that 
while "the extreme edge touches the paper, the graduated 
surface is raided so as to protect it from wear. For accu- 
rate work and very fine division, the metal triangular scale 
is superior to any other form and material, the marking 
point either a hard pencil or a steel pricker, may be run 
down the fine line of graduation, even to i-ioo of an 
inch with extreme accuracy. The triangular scale may 
be fitted with a small handle of bent metal, which helps 
to prevent confusion, as it shows which side should be m 
contact with the paper and which edge uppermost. 
A large assortment of scales is of great convenience m 
figure. A diagonal or inclined line is now drawn, from the 
point marked o on the upper line to a on the lower, and 
through each of the other points on the upper line is 
drawn a parallel line, i, b; 2, c; etc. In crossing the ten 
parallels, the first inclined line, o, a, gains i-io of the 
prime division, consequently in crossing the first parallel 
Fig. 61— Protractor and Plain Scale. 
(Copyrighted by the Keuffel & Esser Co., New York.) 
it gains one-tenth of this distance, or i-ioo of the prime 
division. In crossing the second parallel it has gained 
two-tenths, and so on to the complete distance on the 
lowest parallel. Suppose the dividers to be placed on the 
point representing 5ft., the other point being on o, the 
distance measured is 5ft. Now if the dividers be moved 
Fig- 56— a, single bevel scale, b, double beVel scale, c, triangular 
scale, 
down to the next parallel and opened so that the two 
points are each on its respective vertical and diagonal, the 
distance will have been increased by l-ioo of the prime 
unit. In Fig. 57 the dividers are shown on the fourth 
parallel, the sixth vertical, and the third diagonal; the 
reading, therefore, is: Six feet, three tenths of a foot, 
and four hundredths. The rule for measuring from such 
a scale is, place the dividers on the intersection of the 
parallel indicated by the third figure and the diagonal in- 
dicated by the second figure, moving the other point to 
the vertical indicated by the first figure. The diagonal 
scale was in very common use by the old shipwrights, and 
will be found in all old books and drawings. It is easily 
constructed to any desired scale, and is useful in taking 
off measurements for calculation, which must be in feet, 
tenths and hundredths, and not in inches and fractions. 
The diagonal scale may be constructed with duodecimal 
divisions, giving feet, inches and fractions of an inch, Fig, 
The vernier scale is a device for reading to smaller sub- 
divisions than can be conveniently marked and read on 
the scale itself. In its most common form it consists of a 
small auxiliary scale, sliding beside the main scale. As- 
suming that the main scale is divided into tenths of aa 
inch, then on the vernier a distance equal to nine of these 
divisions of the main .scale is laid off and divided into ten 
equal parts. It will be evident then that each division on 
the vernier is equal to 9-10 of a division of the main 
scale; in other words, each division of the main scale ex- 
ceeds by i-io a division of the vernier. If the two scales 
be adjusted so that the 0 on the vernier coincides with 
any point of division of the main scale, as 10 in Fig. 59, a, 
the reading is simply 10. If the vernier be moved to the 
right until its first division coincides with 11 on the main 
scale, it will be evident that the distance now denoted by 
the 0 of the vernier is greater than before by i-io. 
Successive movements of the vernier to the right 
win show an increase of i-io; as the point 2 on the 
vernier coincides with the point 12 on the main scale, the 
excess beyond 10 becomes 2-10; for 3 and 13 respectively, 
3-10, etc. Fig. 59, b, shows a reading of 10.18; the mark 
8 on the vernier being nearer than any of its fellows to 
some one mark of the main scale. 
The difference between the length of a space on the 
main scale and that on the vernier (in this case i-loo) 
is called the least space, and must be equal to one space of 
the main scale divided by the number of spaces of the 
vernier. In using any instrument with a vernier, the dis- 
tance to be measured is marked by the o of the main 
scale, and the 0 of the vernier; when the instrument is 
adjusted to the distance, the division of the main scale 
immediately preceding the vernier must be read, then 
follow the vernier until that one of its divisions is found 
which coincides most nearly, if not exactly, with some one 
division of the main scale; the number of this division 
gives the required fraction, to be added to the reading 
of the main scale. The vernier i§ found on the planimeter, 
integrator, protracto.r, sextant, barometer and many other 
instruments in common use by navigators, surveyors, 
draftsmen and mechanics. 
The protractor is literally a circular plotting scale, iulU 
divided, a circle or semicircle of horn, metal or cardboard 
with the center marked and the edge divided into 360 
equal parts, or degrees. For ordinary use the smallest 
division is }4 or ^ of a degree ; but the most elaborate 
protractors, with revolving arm and vernier, may meas- 
