142 
THE YOUNG SCIENTIST. 
filed to a point or rounding, so that it will 
not catch and stick in the work. 
It is more particularly desirable that 
saws of this kind should have the teeth so 
sjiaped that all the cutting will be done 
on the pull stroke, and it will always pay 
the amateur to file the teeth so that this 
y ill be the case. 
Another form of this saw is shown at 
iig. where the pad is made of iron in- 
Figfo 4. 
stead of wood. These are purely Amer- 
ican make, and answer very well; they 
are much cheaper, and for many pur- 
poses just as useful for the amateur's pur- 
pose as the more expensive pad. 
Fig. 5 shows a nest of saws all made to 
Fig. 5. 
fit one handle. This is a very convenient 
arrangement, and answers very well 
when an amateur wishes to have a full 
set of saws. The largest blade is called a 
table saw, and will answer very well for 
cutting round large curves. The second- 
sized blade may be used for a compass- 
saw, and will cut circles of a much less 
radius than the table-blade; the smallest 
blade takes the place of the pad or key- 
hole saw, but has the disadvantage of 
being obliged to work with its whole 
length extending from the handle. 
The web-saw, the same as shown in 
Fig. 2, is a long narrow blade, being of 
equal width all its length, and having a 
hole in each end, by which it is connected 
to the handles which pass through the 
frame. These handles are made to fit 
loosely in the frame, and can be turned 
so that the saw will present its teeth in 
any direction ; and the saw can be discon- 
nected from the handles instantly. The 
object of having the saw arranged in this 
manner is to enable the operator to work 
inside frets or scrolls. This is accom- 
plished by first boring a hole through the 
stuff to be cut, and then inserting the 
saw, which must be fastened to the handle 
again, after which the operation of saw- 
ing may be commenced. In using this 
saw it is necessary to observe that the 
blade is in a true line and out of twist. 
The crossbar of the frame prevents the 
saw from working in the stuff very far 
from its edge, thus making it necessary in 
cases where the stuff is wide to complete 
the pattern with pad or compass-saw. 
Some mechanics are very expert with 
the bow-saw, and will turn out very fine 
work with them, but the majority of 
workmen know but little about them, 
and the introduction of the jig-saw and 
the American scroll-saw has completely 
superseded it in the large workshops and 
factories, where it was once quite a com- 
mon tool. 
With regard to filing this class of saws, 
it may be said that all should be treated 
alike, and the method of filing one applies 
to all. 
As shown in previous papers on this 
subject, a saw intended for cross-cutting 
will not rip satisfactorily, neither will a 
saw cross-cut that is designed for ripping ; 
nor will the ripping or cross-cutting saw 
do satisfactory work where the fibres of 
the wood have to be severed at all angles. 
Hence the necessity of giving the class of 
saws under discussion, teeth that partake 
of both the rip and cross-cut teeth. 
This is done by making the teeth point 
pretty well forw^ard, like those shown in 
Fig. 6, and filed square on the back and 
Fig. 6. 
slightly beveling on the cutting edge of 
the tooth. The teeth shown are larger 
than those used in pad-saws or in saws 
