42 
THE YOUNG SCIENTIST. 
use of a mallet ; the one shown at Fig. 4 
presents, perhaps, the handiest shape, as 
It is always i?i the right position when in 
the hand. It may be made 
of beech, hickory or iron- 
wood. It should be light 
and handy. Another useful 
contrivance that can be eas- 
ily made by any handy am- 
ateur is a " router," some- 
times called by workmen a 
" hag's tooth." It consists 
of a piece of hard wood, pre- 
ferably beech, {ibout two inches wide and 
one and a lialf or more inches thick, and 
from five to eight inches long, with a slot 
or mortice cut through the centre to ad- 
mit a chisel or otlier cutting tool, which 
is held in the slot the same as a plane 
iron is kept in place. Fig. 5 shows the 
block, A, and the cutter, b. 
Fig. 4. 
Fig. 5. 
The tool is especially useful for regu- 
lating the depth of groundwork of panels, 
etc. It can be made of various sizes, but 
the most useful will be of the size named, 
and made to admit a cutter about a quar- 
ter of an inch wide. In using this tool 
the groundw^ork is first cut out, to some 
extent, by a quick bent tool ; the cutter 
is set to the depth required, and by work- 
ing the tool backwards and forwards, a 
perfectly flat surface is obtained. The 
stones required for sharpening carving 
tools should be the very best that can be 
obtained. Arkansas or Turkey stones are 
probably the best, but we have got good 
results from Washita stones ; perhaps for 
slips and other small stones it is better 
to procure Arlcansas ones, as they gener- 
ally give the best satisfaction for sharp- 
ening inside work, such as the inside of 
gouges, veining tools, etc. In general, a 
quick cutting stone is the best for large 
tools, and a fine-grainei, slow^ cutting 
one for the small and finer tools. With 
small veiners and parting tools a piece of 
pine is cut — across the grain — so as to fit 
inside of the tool to be sharpened, and 
emery powder and oil is then used to rub 
out the inside of the tool. Other tools 
and contrivances, such as small files of 
various sizes, scrapers of different shapes, 
and cutters of suitable forms, will occur 
as wants to the amateur, w^hen he enlarges 
his field of labor. 
After the inside of a tool has been thor- 
oughly rubbed out, and there is not much 
danger of sharitening it too much from 
the inside, the outside edge should be fin- 
ished off by sharpening on the main oil- 
stone, and when this is done, the tool 
' should be laid flat on the stone and moved 
I gently to and fro, until the required edge 
I is obtained. Care should be taken to keep 
I the edge of the tools perfectly square and 
even. 
I In sharpening the outside of tools with 
I a slip the tool should be held in the left 
hand ; then move the stone sharply up 
I and down the edge with the right hand, 
except in cases of flat 
tools, when the stone 
may be placed on the 
bench, and both 
hands used to grasp 
the tool. The best of 
sperm-oil should be 
used as a lubricant 
on the stone. Other 
clean oils will answer 
tolerably well, but it 
is always better to use 
sperm or olive. Some- 
times emery powder 
or flour emery is used 
on the stone, to in- 
<',rease the cutting 
X)ower, but this is not 
a desirable practice. 
To put a finishing, 
clean-cutting edge on 
the tools, a piece of 
leather may be used. 
This may be glued on 
the top of the oil-stone box, or it may be 
fastened on an independent piece of wood. 
The leather should be plentifully satu- 
rated witli hard mutton tallow and cro- 
Fig. 
