162.--THE CARDBOARD CHAIN.

The reader will probably feel rewarded for any care and patience that

he may bestow on cutting out the cardboard chain. We will suppose that

he has a piece of cardboard measuring 8 in. by 2½ in., though the

dimensions are of no importance. Yet if you want a long chain you

must, of course, take a long strip of cardboard. First rule pencil

lines B B and C C, half an inch from the edges, and also the short

perpendicular lines half an inch apart. (See next page.) Rule lines on

the other side in just the same way, and in order that they shall

coincide it is well to prick through the card with a needle the points

where the short lines end. Now take your penknife and split the card

from A A down to B B, and from D D up to C C. Then cut right through

the card along all the short perpendicular lines, and half through the

card along the short portions of B B and C C that are not dotted. Next

turn the card over and cut half through along the short lines on B B

and C C at the places that are immediately beneath the dotted lines on

the upper side. With a little careful separation of the parts with the

penknife, the cardboard may now be divided into two interlacing

ladder-like portions, as shown in Fig. 2; and if you cut away all the

shaded parts you will get the chain, cut solidly out of the cardboard,

without any join, as shown in the illustrations on page 40.

It is an interesting variant of the puzzle to cut out two keys on a

ring--in the same manner without join.

[Illustration]

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