duction will be of interest to the amateur who essays to
construct a flying machine. Assuming that the size decided upon is
double that of the glider the material for the framework, timber, cloth,
wire, etc., will cost a little more than double. This is because it must
be heavier in proportion to the increased size of the framework, and
heavy material brings a larger price than the lighter goods. If we allow
$20 as the cost of the glider material it will be safe to put down
the cost of that required for a real flying machine framework at $60,
provided the owner builds it himself.

As regards the cost of motor and similar equipment it can only be said
that this depends upon the selection made. There are some reliable
aviation motors which may be had as low as $500, and there are others
which cost as much as $2,000.

Services of Expert Necessary.

No matter what kind of a motor may be selected the services of an expert
will be necessary in its proper installation unless the amateur has
considerable genius in this line himself. As a general thing $25 should
be a liberal allowance for this work. No matter how carefully the engine
may be placed and connected it will be largely a matter of luck if it is
installed in exactly the proper manner at the first attempt. The chances
are that several alterations, prompted by the results of trials, will
have to be made. If this is the case the expert's bill may readily run
up to $50. If the amateur is competent to do this part of the work the
entire item of $50 may, of course, be cut out.

As a general proposition a fairly satisfactory flying machine, one that
will actually fly and carry the operator with it, may be constructed for
$750, but it will lack the better qualities which mark the higher priced
machines. This computation is made on the basis of $60 for material, $50
for services of expert, $600 for motor, etc., and an allowance of $40
for extras.

No man who has the flying machine germ in his system will be long
satisfied with his first moderate price machine, no matter how well it
may work. It's the old story of the automobile "bug" over again. The man
who starts in with a modest $1,000 automobile invariably progresses by
easy stages to the $4,000 or $5,000 class. The natural tendency is to
want the biggest and best attainable within the financial reach of the
owner.

It's exactly the same way with the flying machine convert. The more
proficient he becomes in the manip