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single lever control。
Farman employs a lever to actuate the rudders； but
manipulates the balancing planes by foot levers。
Santos…Dumont uses two hand levers with which to
steer and elevate； but manipulates the planes by means
of an attachment to the back of his outer coat。
Connection With the Levers。
No matter which particular method is employed； the
connection between the levers and the object to be manipulated
is almost invariably by wire。 For instance； from
the steering levers （or lever） two wires connect with opposite
sides of the rudder。 As a lever is moved so as to
draw in the right…hand wire the rudder is drawn to the
right and vice versa。 The operation is exactly the same
as in steering a boat。 It is the same way in changing
the position of the balancing planes。 A movement of
the hands or feet and the machine has changed its
course； or； if the equilibrium is threatened； is back on
an even keel。
Simple as this seems it calls for a cool head； quick
eye； and steady hand。 The least hesitation or a false
movement； and both aviator and craft are in danger。
Which Method is Best？
It would be a bold man who would attempt to pick
out any one of these methods of control and say it was
better than the others。 As in other sections of aeroplane
mechanism each method has its advocates who dwell
learnedly upon its advantages； but the fact remains that
all the various plans work well and give satisfaction。
What the novice is interested in knowing is how the
control is effected； and whether he has become proficient
enough in his manipulation of it to be absolutely dependable
in time of emergency。 No amateur should attempt
a flight alone； until he has thoroughly mastered
the steering and plane control。 If the services and advice of an
experienced aviator are not to be had the
novice should mount his machine on some suitable supports
so it will be well clear of the ground； and； getting
into the operator's seat； proceed to make himself well
acquainted with the operation of the steering wheel and
levers。
Some Things to Be Learned。
He will soon learn that certain movements of the
steering gear produce certain effects on the rudders。 If；
for instance； his machine is equipped with a steering
wheel； he will find that turning the wheel to the right
turns the aeroplane in the same direction； because the
tiller is brought around to the left。 In the same way
he will learn that a given movement of the lever throws
the forward edge of the main plane upward； and that the
machine； getting the impetus of the wind under the concave
surfaces of the planes； will ascend。 In the same
way it will quickly become apparent to him that an opposite
movement of the lever will produce an opposite
effectthe forward edges of the planes will be lowered；
the air will be 〃spilled〃 out to the rear； and the machine
will descend。
The time expended in these preliminary lessons will
be well spent。 It would be an act of folly to attempt to
actually sail the craft without them。
CHAPTER XII。
HOW TO USE THE MACHINE。
It is a mistaken idea that flying machines must be
operated at extreme altitudes。 True； under the impetus
of handsome prizes； and the incentive to advance scientific
knowledge； professional aviators have ascended to
considerable heights； flights at from 500 to 1；500 feet being
now common with such experts as Farman； Bleriot；
Latham； Paulhan； Wright and Curtiss。 The altitude
record at this time is about 4；165 feet； held by Paulhan。
One of the instructions given by experienced aviators
to pupils； and for which they insist upon implicit obeyance； is：
〃If your machine gets more than 30 feet high；
or comes closer to the ground than 6 feet； descend at
once。〃 Such men as Wright and Curtiss will not tolerate
a violation of this rule。 If their instructions are
not strictly complied with they decline to give the offender
further lessons。
Why This Rule Prevails。
There is good reason for this precaution。 The higher
the altitude the more rarefied （thinner） becomes the air；
and the less sustaining power it has。 Consequently the
more difficult it becomes to keep in suspension a given
weight。 When sailing within 30 feet of the ground sustentation
is comparatively easy and； should a fall occur；
the results are not likely to be serious。 On the other
hand； sailing too near the ground is almost as objectionable
in many ways as getting up too high。 If the craft
is navigated too close to the ground trees； shrubs； fences
and other obstructions are liable to be encountered。
There is also the handicap of contrary air currents
diverted by the obstructions referred to； and which will
be explained more fully further on。
How to Make a Start。
Taking it for granted that the beginner has familiarized
himself with the manipulation of the machine； and especially
the control mechanism； the next thing in order
is an actual flight。 It is probable that his machine will
be equipped with a wheeled alighting gear； as the skids
used by the Wrights necessitate the use of a special
starting track。 In this respect the wheeled machine is
much easier to handle so far as novices are concerned
as it may be easily rolled to the trial grounds。 This；
as in the case of the initial experiments； should be a
clear； reasonably level place； free from trees； fences；
rocks and similar obstructions with which there may be
danger of colliding。
The beginner will need the assistance of three men。
One of these should take his position in the rear of the
machine； and one at each end。 On reaching the trial
ground the aviator takes his seat in the machine and；
while the men at the ends hold it steady the one in the rear
assists in retaining it until the operator is ready。 In the
meantime the aviator has started his motor。 Like the
glider the flying machine； in order to accomplish the
desired results； should be headed into the wind。
When the Machine Rises。
Under the impulse of the pushing movement； and assisted
by the motor action； the machine will gradually
rise from the groundprovided it has been properly
proportioned and put together； and everything is in working
order。 This is the time when the aviator requires
a cool head； At a modest distance from the ground use
the control lever to bring the machine on a horizontal
level and overcome the tendency to rise。 The exact
manipulation of this lever depends upon the method of
control adopted； and with this the aviator is supposed
to have thoroughly familiarized himself as previously
advised in Chapter XI。
It is at this juncture that the operator must act
promptly； but with the perfect composure begotten of
confidence。 One of the great drawbacks in aviation by
novices is the tendency to become rattled； and this is
much more prevalent than one might suppose； even
among men who； under other conditio