RADIOTELEGRAPH Y— MARCONI. 119 
Many mechanical analogies could be quoted which show that in 
order to obtain syntony the operating energy must be supplied in the 
form of a sufficient number of small oscillations or impulses properly 
timed. Acoustics furnish us with numerous examples of this fact, 
such as the resonance produced by the well-known tuning fork 
experiment. 
Other illustrations of this principle may be given; e. g., if we have 
to set a heavy pendulum in motion by means of small thrusts or 
impulses, the latter must be timed to the period of the pendulum, as 
otherwise its oscillations would not acquire any appreciable amplitude. 
In 1900 I first adopted the arrangement which is now in general 
use, and which consists (as shown in fig. 3) of the inductive associa- 
tion of the elevated radiating wire with a condenser circuit which may 
be used to store up a considerable amount of electrical energy and 
impart it at a slow rate to the radiating 
wire. 
As is now well known, the oscillations in 
a condenser circuit can be made to persist 
for what is electrically a long period of 
time, and it can be arranged moreover that 
by means of suitable aerials or antenne 
these oscillations are radiated into space 
in the form of a series of waves, which 
through their cumulative effect are emi- 
_ nently suitable for enabling good tuning 
and syntony to be obtained between the 
transmitter and receiver. 
The circuits, consisting of the condenser 
circuit and the elevated aerial or radiating 
circuit, were more or less closely coupled 
to each other. By adjusting the inductance in the elevated con- 
ductor, and by the employment of the right value of capacity or 
inductance required in the condenser circuit, the two circuits were 
brought into electrical resonance, a condition which I first pointed 
out as being essential in order to obtain efficient radiation and good 
tuning. 
The receiver (as shown in fig. 4) also consists of an elevated con- 
ductor or aerial connected to earth or capacity through an oscil- 
lating transformer. The latter also contains the condenser and 
detector, the circuits being made to have approximately the same 
electrical time period as that of the transmitter circuits. 
At the long distance station situated at Clifden, in Ireland, the 
arrangement which has given the best results is based substantially 
upon my syntonic system of 1900, to which have been added numerous 
improvements. 
8 
8 
tA 
3 
Fi4. 3. 
