Now the engineer,who lately gave an account before a technical body of a novel remedy against statics based on a "heretofore unknown law of nature,"seems to have been as reckless as myself when he contended that these disturbances propagate up and down,while those of a transmitter proceed along the earth.It would mean that a condenser,as this globe,with its gaseous envelope,could be charged and discharged in a manner quite contrary to the fundamental teachings propounded in every elemental text-book of physics.Such a supposition would have been condemned as erroneous,even in Franklin"s time,for the facts bearing on this were then well known and the identity between atmospheric electricity and that developed by machines was fully established.Obviously,natural and artificial disturbances propagate through the earth and the air in exactly the same way,and both set up electromotive forces in the horizontal,as well as vertical,sense.Interference can not be overcome by any such methods as were proposed.The truth is this:in the air the potential increases at the rate of about fifty volts per foot of elevation,owing to which there may be a difference of pressure amounting to twenty,or even forty thousand volts between the upper and lower ends of the antenna.The masses of the charged atmosphere are constantly in motion and give up electricity to the conductor,not continuously but rather disruptively,this producing a grinding noise in a sensitive telephonic receiver.The higher the terminal and the greater the space encompassed by the wires,the more pronounced is the effect,but it must be understood that it is purely local and has little to do with the real trouble.
In 1900,while perfecting my wireless system,one form of apparatus comprised four antennae.These were carefully calibrated to the same frequency and connected in multiple with the object of magnifying the action,in receiving from any direction.When Idesired to ascertain the origin of the transmitted impulses,each diagonally situated pair was put in series with a primary coil energizing the detector circuit.In the former case the sound was loud in the telephone;in the latter it ceased,as expected,the two antennae neutralizing each other,but the true statics manifested themselves in both instances and Ihad to devise special preventives embodying different principles.
By employing receivers connected to two points of the ground,as suggested by me long ago,this trouble caused by the charged air,which is very serious in the structures as now built,is nullified and besides,the liability of all kinds of interference is reduced to about one-half,because of the directional character of the circuit.This was perfectly self-evident,but came as a revelation to some simple-minded wireless folks whose experience was confined to forms of apparatus that could have been improved with an axe,and they have been disposing of the bear"s skin before killing it.If it were true that strays performed such antics,it would be easy to get rid of them by receiving without aerials.But,as a matter of fact,a wire buried in the ground which,conforming to this view,should be absolutely immune,is more susceptible to certain extraneous impulses than one placed vertically in the air.To state it fairly,a slight progress has been made,but not by virtue of any particular method or device.It was achieved simply by discarding the enormous structures,which are bad enough for transmission but wholly unsuitable for reception,and adopting a more appropriate type of receiver.As Ipointed out in a previous article,to dispose of this difficulty for good,a radical change must be made in the system,and the sooner this is done the better.
It would be calamitous,indeed,if at this time when the art is in its infancy and the vast majority,not excepting even experts,have no conception of its ultimate possibilities,a measure would be rushed through the legislature making it a government monopoly.This was proposed a few weeks ago by Secretary Daniels,and no doubt that distinguished official has made his appeal to the Senate and House of Representatives with sincere conviction.But universal evidence unmistakably shows that the best results are always obtained in healthful commercial competition.There are,however,exceptional reasons why wireless should be given the fullest freedom of development.In the first place it offers prospects immeasurably greater and more vital to betterment of human life than any other invention or discovery in the history of man.Then again,it must be understood that this wonderful art has been,in its entirety,evolved here and can be called "American"with more right and propriety than the telephone,the incandescent lamp or the aeroplane.