THE YOUNG SCIENTIST. 
45 
^connected by bars at g g, and h h, will 
toe a substitute for a metal framework 
made for a similar ])urpose. A cur- 
tain in needleworlc iianfts well on such a 
frame as this, and fullils the purpose of 
.screeiiius: what it is wislied to hide as 
well, or better than many of the more 
^elaborate designs. 
The total length of leaf from point to 
point is 175 inches ; greatest width at top, 
54 inches ; height of standard, 124 inches ; 
width at bottom, 8 inches; width of shaft, 
■2h inches. Cross feet. Fig. 4, are 7 inches 
long and one and a half inches wide. 
Walnut or mahogany would make excel- 
lent material for this screen. 
Something About Saws. 
BY " OUR NED." 
T is an old saying that " A bad 
workman quarrels with his 
tools," It might also be said 
with equal force that Bad 
tools make a good workman cranky." 
Particularly is this so if the " bad " tool 
happens to be a saw. 
An amateur's first experience with a 
new saw — cross-cut or rip — is generally of 
a pleasant nature, because then the saws 
are straight, sharp, and in good condition, 
and a saw in fine condition and sharp is 
•one of the most pleasing tools to work 
with, and the most unsatisfactory if the 
reverse is the case. The reader will no- 
tice that I have made a distinction with a 
difference in using the tertns " condition " 
and "sharp," and I will clear up this 
point before i^roceeding further. I use 
the term "good condition" to denote 
that the blade is in perfect order, devoid 
of "kinks" or "buckles," the line of 
teeth regular, and this line slightly 
curved, the teeth of ecpial size and "set," 
and at the proper angle with regard to the 
line of teeth. When all these things are 
complied with, in accordance with well- 
defined rules for the purpose, the saw 
will cut tolerably well, though it may not 
be very sharp. To be sharp a saw must 
possess keen points, and the edges of 
each tooth must be sharp and well-de- 
fined, and the angles of each tooth, with 
regard to the sides of the saw, must be 
regular and in accordance with rules I 
shall exjilain further on. A saw may be 
" sharp," yet perfectly useless as a cutting 
tool; therefore, let me impress on your 
minds the necessity of keeping this tool 
m the best of order. It is irni)ossible to 
cut off a piece of board, plank or scant- 
ling straight and square with a saw whose 
teeth are formed something after the 
fashion of those shown in Ficr. A. 
Fig. A. 
This engraving, in a measure, repre- 
sents the condition of many amateur 
cross-cut saws I have met with, and 
which, to my knowledge, have caused 
nuiny an ingenious amateur to abandon 
amateur work altogether, so discouraging- 
have been the results of their struggling 
labors with the tool. It might well be said 
of persons using such an instrument that 
they are on " a ragged edge." 
Now, then, how can the amateur take 
care of his saws and keep them in good 
I condition? I will endeavor to answer this 
I question in a plain way, so that the reader 
jwill not get mystified or "mixed." In 
j the first place, if you have not already 
purchased saws, see to it that, when you 
I do buy, you get good ones, saws made by 
I some good reliable firm who have earned 
I a reputation for the excellence and elfi- 
j ciency of their manufactures. Kemember 
jthat in this, as in all similar matters, you 
: must pay a good i)rice for a good article. 
Cheap saws, like cheap fruit, may look 
I very well, but they contain the canker- 
worm of disappointment in their cores. 
When the saws are once taken home they 
should be rubbed over with an oily rag 
and either hung up or placed carefully 
away in a chest, if not in use. Never try 
to force a saw through a piece of stuff; if 
the material being sawed should warp or 
I twist, as is often the case while being cut, 
and close up the saw-kerf so as to pinch 
jthe saw, any further attempt at sawing 
should cease, until the kerf is wedged 
open or the saw otherwise released. It is 
