The Scientific American Boy by A. Russell Bond

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The instrument was mounted on a tripod similar to the one used for our
surveying instrument. To this it was attached by means of a bolt, which
passed through the center of the baseboard and the tripod head.

The Screen.

[Illustration: Fig. 157. Section through Shutter.]

[Illustration: Fig. 158. General View of Screen.]

The screen, or shutter, of the heliograph was mounted on a separate
tripod, so as to prevent shaking the mirror when it was operated. It was
made something like a window shutter. We cut out two slats, each 2-1/2
inches wide and 6 inches long. They were made of hardwood 3/8 inch thick.
The upper and lower edges were tapered down to a thickness of 3/16 inch.
Light nails were driven into the slats at the ends, and the nail heads
were then filed off so that the projecting ends formed trunnions for the
slats to turn on. The slats were linked to a connecting rod with double
point tacks. A small double point tack was driven into the upper edge of
each slat about 1/2 inch from the right hand end. Then through each of
these tacks we hooked a second double point tack and drove it into the
rod. The tacks on the rod were placed just 2 inches apart. A substantial
frame was then made of 3/4-inch stuff 1-1/2 inches wide. The frame was
square, with an opening that measured 6 inches each way, into which the
slats were fitted. Before nailing the frame together we drilled holes in
the side pieces for the trunnions of the slats to turn in. These holes
were just 1-3/4 inches apart. After the slats had been set in place, the
frame was fastened together and then nailed to a baseboard, which was
fastened by a bolt to the tripod. The shutter was operated by a key
something like a telegraph key. It was made of a narrow stick of wood
hinged at one end to the lower strip of the shutter frame, and a spool
sawed in two was fastened to the other end to serve as a handle for the
key. A string connected the key with the connecting rod. The slats were
kept closed by a spring, which was fastened at one end to the connecting
rod and at the other to the top of the frame. At first we used a rubber
band for this purpose, but it soon wore out, so we then made a spiral
spring out of stiff spring brass wire by wrapping it around a pencil. When
the key was pressed down the slats would be turned open, as shown in Fig.
159; but as soon as the key was released the spring would pull them back
again.

Focusing the Instrument.

[Illustration: Fig. 159. The Heliograph in Operation.]

We were now ready to commence operations with our instruments. The
heliograph was set up on the ledge at the top of the cliff. First the disk
was turned down, uncovering the point of the sighting rod. Then Bill
sighted through the unsilvered spot in the mirror and shifted the rod up
and down until the tip end came squarely in line with the door of our
straw hut, where Jack was seated, notebook in hand, to take down our
message. Reddy stood by him with his wigwag flag to answer back. When the
instrument was properly sighted the shutter was set up directly in front
of it and the sighting disk turned up to cover the point of the sighting
rod. Then came the rather troublesome task of focusing the mirror. The
mirror reflected a square panel of light, in the center of which there was
a small shadow spot made by the unsilvered peep hole. The object was to
get this shadow to fall on the center of the sighting disk. We knew that
then the mirror would reflect the sunlight squarely on the straw hut. We
found it quite easy to direct this shadow spot to the disk by holding a
sheet of paper in front of the mirror six or eight inches away, and
following up the spot on the paper until it reached the disk.

Heliograph Signaling.

[Illustration: Fig. 160. Top View, showing position of Mirror and Shutter.]

When at last we succeeded in properly focusing the mirror Bill pressed the
key down three times, sending three quick flashes to Jack as a signal that
he was ready to begin. Reddy wigwagged back O. K., and then the first
heliographic message was sent from the ledge to the island. It was a
rather mixed-up message, and kept Jim and Reddy wigwagging back and forth
very strenuously to straighten matters out. It was my duty to keep the
mirror focused. As the sun moved across the sky the shadow spot would move
off the disk, and I had to keep shifting the mirror to bring the spot back
where it belonged. We used the International Telegraph Code, which we had
been studying every evening for a week, but it was many weeks before we
learned how to use it correctly, even slowly. The International Telegraph
Code is as follows:

A . - B - . . . C - . - . D - . . E -
F . . - . G - - . H . . . . I . . J . - - -
K - . - L . - . . M - - N - . O - - -
P. - - . Q - - . - R . - . S . . . T -
U . . - V . . . - W . - - X - . . - Y - . - -
Z - - . . 1 . - - - 2 . . - - - 3 . . . - - 4 . . . . -
5 . . . . . 6 - . . . . 7 - . . . 8 - - - . 9 - - - - .
0 - - - - -

The three short flashes Bill sent represented the letter S, which stood
for the word "signal." A was formed by a short flash followed by a long
flash; B by a long flash followed by three short ones, and so on. The key
was held down three times as long for the long flash as for the short one.
We found the best way of learning to send the signals properly was to
count 1 for each short flash, and for each pause between parts of the
letter, and 3 for each dash and for each pause between letters. Between
words we counted 6. Thus, for the letter A the key would be down when we
counted 1, up when we counted 2, down while we counted 3, 4, 5, and up
while we counted 6, 7, 8, for the pause after each letter. It was rather a
confusing code, I admit, but in time we mastered it, all but Reddy and
Fred, who never would learn, but instead used the wigwag code, letting a
short flash stand for 1, a long flash for 2 and a double long flash for 3.

The Double Mirror Instrument.

[Illustration: Fig. 161. The Double Mirror Instrument.]

Our heliographing instrument did excellent service sending flashes from
the cliff to the island, but we couldn't make it work very well sending
messages from the island to the cliff, because we had to face almost due
north, and then the sun was nearly always at our backs and couldn't shine
squarely on the mirror. This led to our building a double mirrored
heliograph the following summer. To begin with, we built an instrument
which was the exact duplicate of our first heliograph; then, in addition,
to fit in the socket of the sighting rod, we rigged up a second mirror,
which was mounted in exactly the same way as the first. The second mirror
was called the station mirror, and differed from the other, or sun mirror,
in having a small patch of white paper pasted at the center instead of a
peep hole. When using this instrument, we set it up so that the station
mirror faced the ledge, then by sighting through the hole in the sun
mirror at the reflection in the station mirror we could see just what was
in focus. The station mirror had to be moved until the patch at its center
hid the ledge from view. After that the sun mirror was shifted until the
shadow spot fell on the white patch of the station mirror. When once the
station mirror was focused, it could be clamped tightly in place by
screwing up the trunnion and swivel nuts. But the sun mirror had to be
constantly shifted to keep the shadow on the patch. Another way of
focusing the mirrors was to stand behind the instrument with the head
close to the station mirror, shift the sun mirror until the entire station
mirror was reflected in it, with the white patch squarely over the
unsilvered spot; then still looking at the sun mirror, the station mirror
was shifted until the reflection of the distant station was brought
squarely in line with the unsilvered spot on the mirror. The station
mirror was now firmly bolted and the sun mirror adjusted until the shadow
spot fell on the paper patch.

[Illustration: Fig. 162. Top View, showing position of the Two Mirrors
and the Screen.]

CHAPTER XIV.

ICE BOATS, SLEDGES AND TOBOGGANS.

As our vacation was drawing to a close, we began to make plans for the
Christmas holidays. Our previous Christmas vacation had been so completely
taken up with preparations for the trip to Willow Clump Island that we had
had no time for the trip itself. We resolved this time to have everything
ready beforehand, so that we could spend the entire two weeks in solid
pleasure. Our skate sails and snow shoes were stored in the attic, ready
for use. If we were to make a trip in the snow we would need a sledge, and
then, too, we wanted to make an ice boat. It would hardly pay to build
these on the island and then cart them home, so it was decided to break up
camp a couple of weeks before school commenced.

Breaking Camp.

Consequently, on the first day of September we gathered up our belongings,
corraled our chickens, packed our goods, and the next day started for
home. Mr. Schreiner, in response to a letter from the secretary, came down
with a large wagon in which the majority of the things were packed. The
rest of our luggage was stowed in the scow and the canoes, and these were
towed down the canal, as before. We reached home late in the afternoon,
tired and hungry. It was a treat to sit at the table again and eat some of
Mother's appetizing dishes. And say, wasn't that pie great, though! My,
how ravenous we were! And then a soft, comfortable bed with spotless white
sheets and pillow cases. How soundly we did sleep that night! You can just
bet we were all glad enough to get back to civilization, though, of
course, no one could have dragged out the confession from a single one of
us.

The Ice Boat.

[Illustration: Fig. 163. The Backbone.]

School commenced on the 20th of September that year, so we hadn't much
time to spare. Work was begun immediately on the ice boat. Our first ice
boat was rather a crude one. A 2 by 4 inch scantling 14 feet long was used
for the backbone of the boat. The scantling was placed on edge, and to
lighten it and improve its appearance it was tapered fore and aft from a
point 4 feet from the bow end. The thickness of the ends of the backbone
was but 2 inches, as shown in Fig. 163. To the under edge of the backbone,
5 feet from the forward end, a crosspiece was nailed. This crosspiece was
a 1-inch board 6 inches wide and 9 feet long. Braces were then run from
the ends of the crosspiece to the forward and rear ends of the backbone,
and at the rear end several boards nailed across the braces served as a
seat for the boat.

[Illustration: Fig. 164. Frame of the Ice Boat.]

[Illustration: Fig. 165. Runner Shoe.]

[Illustration: Fig. 166. The Rudder Shoe.]

Our next task was to rig up the runners. For these we used skates, which
were so arranged that we could remove them whenever we wanted to. Three
blocks of wood were used for the runner shoes. Two of them were cut from a
2 by 4 scantling and measured a foot in length. The third block was only 1
inch thick, but was otherwise of the same dimensions. The skates were laid
face downward on the blocks with the clamping levers open; then we marked
the places where the clamping jaws touched the wood and drilled holes at
these points. The forward end of each block was also tapered off to fit
flat against the face of the skate. Then by inserting the jaws in the
holes and closing the levers, the skate was clamped to the block, just as
it would be to a shoe. The two 2-inch blocks were bolted to the ends of
the crosspiece, but the third block needed further attention, as it was to
be used for the rudder or steering runner.

The rudder post was shaped from a block of hardwood 3 inches square and 10
inches long. Two inches from the lower end saw cuts were made in the side
of the block to a depth of 3/4 inch. Then with a chisel the sides were
split off, forming a large pin with a square shank 8 inches long. Next the
corners of the shank were cut off, rounding it to a diameter of 1-1/2
inches. The runner block was fastened securely to the head of the rudder
post with screws. A 1-1/2-inch hole was now drilled into the backbone at
the stern end to receive the rudder post. A tiller was next cut out of a
1-inch board to the shape shown in Fig. 167. A slot was cut in the end of
the tiller, and the latter fitted snugly over the top of the post, where
it was held in place by screws threaded in through the sides.

[Illustration: Fig. 167. The Tiller.]

[Illustration: Fig. 168. Drilling the Mast Step.]

The mast of our boat was a pole 8 feet long, tapering from a diameter 2
inches at the base to 1-1/2 inches at the top. A step for the mast was cut
from a 2 by 4 block 8 inches long. A 2-inch hole was drilled into the face
of this block. We had no drill large enough to bore this hole, but
accomplished the same result by drilling eight 1/2-inch holes inside of a
2-inch circle (Fig. 168), and then used a chisel to cut off the projecting
pieces. The mast step was firmly bolted to the backbone at its thickest
part, that is, just four feet from the forward end. The mast was braced
with stay ropes stretched from the top to the forward end of the backbone
and to the ends of the crosspiece. A 9-foot pole, tapering from 1-1/2
inches to 1 inch in diameter, was used for the boom of the mainsail, and
for the gaff we used a 6-foot pole of the same diameter.

[Illustration: Fig. 169. The Mainsail.]

[Illustration: Fig. 170. Jaws of the Boom.]

The dimensions of the mainsail are given in Fig. 169. For mast hoops we
used curtain rings. Five were attached to the sail along the luff, and one
was fastened with a piece of leather to the end of the gaff. We used a
different scheme for holding the boom to the mast. The forward end of the
boom was flattened at the sides and a couple of cheek blocks were bolted
on, forming jaws of the shape indicated in Fig. 170. The jaws were
whittled out to fit nicely around the mast, and were kept from slipping
off by a piece of rope passed around the mast and threaded through the
ends of the cheek blocks. Half a dozen small pulley blocks were now
procured, of the type used on awnings. A rope called the throat halyard
was strung from the throat or forward end of the gaff through a pulley
block near the top of the mast, and led down to the backbone, where it was
"belayed," or wrapped around a cleat. The cleat, which was whittled out of
a stick of wood, was made in the form indicated in Fig. 171. A short
length of rope was strung through a pulley block and tied with some slack
to the upper end and to the center of the gaff. This rope is called a
"bridle," and to the pulley block on this "bridle" a rope was attached
called the "peak halyard." The peak halyard was passed through a pulley
block at the top of the mast, and belayed on a cleat at the side of the
backbone. For the main sheet (that is, the rope used for guiding the
mainsail) two pulley blocks were fastened to the backbone, one just in
front of the seat and the other a few feet further forward, and two more
were lashed to the boom, midway between these blocks. The sheet was
fastened near the aft end of the backbone and then strung through the
blocks in the order illustrated, the free end of the sheet being brought
back to the seat, where a cleat was provided, to which it could be secured
when desired.

[Illustration: Fig. 171. A Cleat.]

[Illustration: Fig. 172. The Jib-sail.]

[Illustration: Fig. 173. The Ice Boat Completed.]

The jib-sail was now cut out to the dimensions given in Fig. 172. The foot
of the sail was lashed to a jib-boom 3 feet 4 inches long. The jib-boom
was attached to the backbone at its fore end by means of a couple of screw
eyes. The eye of one of these was pried open, linked through the other
and then closed again. One of the screw eyes was now screwed into the head
of the jib-boom and the other was threaded into the end of the backbone.
The upper corner or "head" of the jib was tied to a jib-halyard, which
passed through a block at the top of the mast, and was secured on a cleat
on the backbone. On the jib we used two sheets. They were attached to the
end of the jib-boom and passed on opposite sides of the mast through
blocks on the crosspiece to the stern of the boat, where separate cleats
were provided for them.

This completed our ice boat, and a very pretty little boat she was. It was
with great reluctance that we furled the sails, unstepped the mast, and
stowed away the parts in our attic until old Jack Frost should wake up and
furnish us with a field of smooth ice.

The Sledge.

[Illustration: Fig. 174. A Spacing Block.]

[Illustration: Fig. 175. The Runners and Rails Spaced Apart.]

[Illustration: Fig. 176. The Sledge.]

Our sledge was patterned after a picture of one used by Peary in one of
his Arctic expeditions. First we got four strips of hickory 1 inch thick,
1-1/2 inches wide and 8 feet long for the runners and side rails.
Beginning 18 inches from the ends, each stick was tapered gradually to a
thickness of 1/2 an inch. Then we made eight spreaders or spacing blocks,
each 1-1/2 inches thick, 2-1/2 inches wide and 11 inches long. In each
end a notch 1/2 inch deep was cut to receive the runners and side rails.
In the edge of each block, midway of its length, a slot 1 inch deep was
cut to receive the cross sticks of the sledge. First we nailed the runners
and rails to the blocks, fastening them with screws, spacing the blocks 16
inches from the ends, and 20 inches apart from center to center. Then we
bent the ends of the rails and runners together, fastening them with
bolts, as in Fig. 175. Four crosspieces, or floor beams, were cut out of a
1-inch board, each 2 inches wide and 30 inches long. These were fitted
into the slots in the space blocks and secured with screws. A cross stick
was also fastened between the rails and runners at the forward end. On the
floor beams we nailed a flooring of 1/2-inch slats, 2 inches wide and 6
feet long. At the rear end these slats projected 8 inches beyond the last
space block and over them a cross slat was nailed. A stick of hickory
4-1/2 feet long was soaked in hot water, as described on page 39, and was
bent to an U-shape. The ends were then fitted over the first cross stick,
and under the first floor supports, and securely nailed in place. Another
stick of hickory 6 feet long was similarly bent, and the ends slipped over
the rear cross slats and fitted against the rear space blocks, in which
position the stick was securely nailed. It was our intention to shoe the
runners with strips of brass, but these were not procurable in our
village, and we had no time to go down to Millville. However, the village
blacksmith came to our rescue and shod our sledge with sleigh runner iron.

We had planned to make two more devices for our winter sports--a toboggan
and a peculiar looking contrivance called a "rennwolf," a picture of which
Dutchy happened to unearth in one of his father's books. Unfortunately
Bill and I had to return to school before either of these was completed.
However, the work was entrusted to Reddy, who was quite handy with tools,
and Jack, who was made secretary pro tempore, took notes on the work.

The Toboggan.

The toboggan was made of light flexible hickory boards, 1/4 of an inch
thick, 6 inches wide and 8-1/2 feet long. Three of these boards were used,
and they were fastened together with cross sticks or battens, about 3
inches wide and 1/2 an inch thick. There were six of these battens spaced
about 15 inches apart, and secured to the floor boards with flathead
screws introduced from the under side and countersunk so that the heads
would not project below the bottom of the toboggan. At the forward end we
screwed on a head piece of oak, 3/4 of an inch thick, 1-1/2 inches wide
and 20 inches long. The head piece was fastened to the under side of the
boards, so that when they were curved up into a hood it would lie on top.
The ends of the head piece, which projected 1 inch each side of the
boards, were notched to hold the rope, which was tied fast after the
boards had been steamed. The boards were steamed by wrapping them in
burlap for a distance of 2 feet from the forward end, and pouring boiling
water over them, as was done with the snow shoes (page 39). Before bending
the boards we had fixed screw eyes in the ends of each batten, except the
forward one; a rope had been strung through these screw eyes and the ends
were now tied to the head piece and drawn tight so as to bend the boards
into a graceful curve. In this way the ropes were of service not only for
curving the front end into a hood, but also for side rails, to hold on by
when shooting swiftly around curves.

[Illustration: Fig. 177. Tying Down the Head Piece of the Toboggan.]

[Illustration: Fig. 178. The Toboggan.]

The Rennwolf.

[Illustration: Fig. 179. Dimensions of Rennwolf.]

The runners of the rennwolf were made of hickory strips, 1 inch thick, 2
inches wide and 8 feet long. At their forward ends these strips were
tapered down to a thickness of 1/2 an inch and curved upward. About 30
inches from the rear end of each runner an upright post was nailed. The
post was 3 feet long and was braced by a diagonal brace 24 inches long, as
shown in Fig. 179. A tie bar was nailed to the post about 6 or 8 inches
from the bottom and connected with the forward curved end of the runner.

The two runners were now placed parallel to each other about 18 inches
apart, and connected by four cross bars, one at the forward end, and three
on the upright posts, in about the positions illustrated. The upper cross
bar was extended 6 inches beyond the posts at each side, and served as a
handle for guiding the queer craft. An 18-inch square board was used for
the seat of the rennwolf. It rested on the second cross-bar of the post
about 12 inches from the runners, and the forward end was supported on
legs nailed to the tie bars. On each runner back of the posts a loop of
leather was nailed, large enough to receive the toe of one shoe.

When using this odd sled one foot would rest on the runner with the toe in
the strap, and by kicking out against the snow or ice with the other foot
the rennwolf would be made to spin along at a rapid rate. Of course, when
coasting both feet would rest on the runners and the sled was steered by
an occasional side push at the right or left. Owing to the great length of
the runners the rennwolf would easily ride over uneven surfaces and thin
spots in the ice.

[Illustration: Fig. 180. The Rennwolf in Use.]

Ice Creepers.

In order to provide a better hold for the propelling foot, we fastened
around the toe a strap of leather, through which a number of long tacks
projected. Their sharp points would stick into the ice, and prevent the
foot from slipping. The seat of the rennwolf was convenient for carrying a
coat or any light luggage, and it was often used to give a friend a very
exhilarating ride.

[Illustration: Fig. 181. The Ice Creeper.]

CHAPTER XV.

THE SUBTERRANEAN CLUB.

I am afraid we were not very glad to get back to school that fall. It
seemed very hard to give up the sport we had been having, and our heads
were brimful of new schemes which we could hardly wait to put into
practice. But we soon learned that there are many things that could be
done during recreation hours at school. We had intended building a cave on
our island that summer, but our vacation came to an end before we got
around to it. There seemed no reason why we shouldn't dig one in the woods
at the back of the schoolhouse.

A Cave-in.

Bill had read somewhere that if you dig a cave under a tree the roots of
the tree will support the ground on top and make a natural and substantial
roof. It sounded very reasonable, we thought; in fact, we never questioned
the truth of the statement, because we had somehow gotten the notion that
books were never wrong, and that whatever was set up in type must surely
be so. But events proved that the man who wrote that book had never
attempted to build a cave in the manner he described, at least not in the
loose, sandy soil of south Jersey. A large spreading cedar was selected as
the tree which should support the roof of our cave. It was situated on a
mound at the edge of the woods. First a passageway, or ditch, was dug at
the bottom, and then we begun tunneling in the side of the mound under the
roots of the tree. For a while the ground above held, and our tunnel had
reached a length of about four feet, when suddenly, without the slightest
warning, the sandy soil gave way and we were engulfed. Bill, who was
furthest within the cave, was almost entirely covered, while I was buried
to the shoulders. A crowd of boys came to our assistance and dug us out.
Poor Bill was almost smothered before they scooped the sand away from
around his mouth and nose. The boys made slow work of it, having to dig
with their hands and a couple of shingles, because the two spades we had
were buried with us at the bottom of the cave.

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