THE YOUNG SCIENTIST. 
3 
running edge of the skate is filed away 
a little at the rear end n o, and it is 
fastened to the runner at n, with a quarter 
inch bolt 3 inches long, as shown at m n. 
The skate should be made slightly con- 
•cave on its lower edge, so that when it is 
drawn up, by the bolt m n, it will be tight 
against the entire bottom of the groove in 
the runner. When it is drawn up into 
its place, it must be perfectly straight on 
the bottom or running edge. 
Any good blacksmith can make the 
skates at slight expense. Care must be 
taken to keep the running edge, /, sharp. 
If any part of it becomes battered it must 
be smoothed and sharpened with a file. 
No difficulty is experienced in drilling the 
holes, d d and n, through the iron corner- 
wise, if a flat spot is first filed, so as to start 
the drill. 
The sides of the runners are sloped 
from the skates to a height of 2 inches as 
shown at v I, and r k. 
The steering runner v l, is the same 
length and thickness as the forward run- 
ners, but is only about inches high. A 
K'ircular block 12 inches in diameter and 
2 inches thick, is fastened to the top of 
the runner as shown at x, so that its 
centre is directly over the middle point of 
the running edge of the skate. The tiller 
shaft, X Y, is a piece of inch round iron 
about 10 inches long. It is squared and 
slightly tapered at its lower end so as to 
fit tightly into a mortice in the block and 
runner. Its top end, y, is squared to fit the 
socket of the tiller, m. The shaft is 
fastened to the runner by a screw or pin 
through a hole drilled for the purpose, 
shown at x. 
A one inch hole for the tiller shaft is 
bored down through the middle of the 
keel at a point about 12 inches from the 
stern. A piece of half inch board, 12 
inches in diameter, with a one inch hole 
through its centre, is screwed to the under 
side of the floor, so that the hole co- 
incides with the hole bored through 
the keel. The board should be placed 
so as to afford a smooth bearing tor the 
block on the runner. The hole must be 
so that the tiller shaft will turn in it 
easily, and yet not have too much play. 
If the bearing surfaces are rubbed with a 
mixture of stove blacking and oil, the 
friction will be greatly reduced. 
The tiller handle must be fitted to the 
shaft so that it will be exactly in line with 
the runner. The boat is steered just the 
same as any sail boat, but it is much more 
sensitive to the action of the rudder. 
The bowsprit is stayed by lines from b 
to F and H. The mast is stayed by lines 
to the same points. 
When the boat is on a level place, the 
frame should be level and the entire run- 
ning edge of each skate should have a 
full bearing on the ice. 
Three Amateur Workers— and What 
They Did-V. 
BY FRED, T. HODGSON. 
THE next thing Fred was instructed to 
do was to joint the board he had 
" dressed,"— and here let me explain 
what is meant by "dressed" when used 
in this connection : " dressed " stuff is that 
which has been taken from the rough, 
and planed and made smooth. Stuff is 
said to be "dressed" on one side, when 
only one side is planed. When one side 
and one edge, or both edges are planed, 
it is said to be " dressed " on one side and 
one edge, or one side and both edges. 
And when planed on both sides and both 
edges, it is said to be "dressed" all 
round. 
To joint the board conveniently, it was 
necessary to place one end in the bench 
screw-chops, the other end being held up 
in place by the movable peg in the side of 
the bench. In jointing the edge, Fred 
found that he had to hold the jointer 
plane somewhat differently than he held 
the jack plane. The thumb had to 
rest on the top of the plane, and the 
fingers were bent under the face to sup- 
port it, the narrow edge of the boar(i not 
affording sufficient base to keep the plane 
steady. 
The sole of the plane must be kept at 
right angles with the side or face of the 
board whilst jointing. The reason of 
this is quite clear ; for it must be evident 
that if the joints of two boards are to fit 
with their edges together, they will not 
