The Upper Regions of the Air as Current Conductors

There are a number of striking and important electrical and magnetic phenomena, which though giving rise to speculation and hypotheses, have not yet been explained by generally accepted theories. Among these we may mention the earth’s magnetism and electrical storms. A satisfactory explanation of the cause of these phenomena would indeed be a great step in advance on our present knowledge and might indeed lead to results now scarcely within the limits of legitimate speculation.

Undismayed by the numerous and conflicting theories of the past, Prof. W. P. Trowbridge has recently come forward with a new hypothesis which, even if not unassailable in all its details, is nevertheless highly interesting and deserving of more than passing notice. As explained by him in this month’s “Forum,” if we ascend a sufficient distance the layer of air which surrounds the earth we there find all the conditions requisite for the production of the two phenomena mentioned above, and incidentally a medium which can transmit X-rays. Having in mind the fact that at great altitudes the air is so rarefied as to constitute a good conductor and the further fact that the air absorbs numerous rays emanating from the sun, especially those of short wave length, Prof. Trowbridge asks: Can the disappearance of the short waves of light have anything to do with the production of electrical storms and the appearance of this weird new form of energy? and, Can this disappearance be connected in any way with the production of magnetism of the earth?

Starting with the proposition that the energy involved in the production of these phenomena emanates from the sun primarily, Prof. Trowbridge propounds the further question whether it is not possible that the short waves of energy may in some way produce electrical and magnetic effects in the upper regions of the air, and thus, being transformed, fail to manifest themselves as light at lower altitudes. It is Prof. Trowbridge’s main contention that the sun’s rays contain the short wave lengths assigned to the X-rays and that, though absorbed by the lower strata of the atmosphere, they exist at the higher altitudes; and that they are instrumental in producing the electricity of the atmosphere and the magnetism of the earth.

Fortifying himself by some recent researches Prof. Trowbridge holds that the solar X-rays give an electrical charge to our atmosphere. The rotation of the earth on its axis would then cause an accumulation of electricity on one side of the earth and a diminution of electricity on the other. We should, therefore, expect a fall of electric pressure between the regions just entering daylight and those in the full glare of the sun. This condition I would direct the resulting electric current from east to west, or in the direction opposite to that of the earth’s rotation.

The current thus established, according to Prof. Trowbridge, is sufficient to account for the main points of his thesis. The electrical disturbances, such as thunder storms, in the lower regions, might thus be accounted for as being the result of great commotions in the air which constitutes a vast atmospheric sea and due to a local descent of high electrical conditions prevailing in the upper regions. The Northern Lights, again, may, according to the same theory, be due to a dissipation of a portion of the electrical discharge, through layers of rarefied and well conducting air.

Reasoning in an analogous way, the currents existing in the upper well-conducting regions act as a solenoid upon the earth beneath and form the magnetic poles observed. In support of the solenoidal action, Prof. Trowbridge points out that on no other theory could the great distance between the north and south pole be explained; no permanent magnet could have any such length without exhibiting consequent poles. As no currents adequate to produce the poles of the earth have yet been discovered in or on the earth, they may, if they exist, circulate in the upper regions.

This entire reasoning depends of course upon the assumption of the great conductivity of the rarefied, upper regions of the air. This brings Prof. Trowbridge to the question of the practicability of Mr. Tesla’s recent proposal to utilize those regions as a conducting medium for the electrical transmission of power. Prof. Trowbridge’s experience, based on experiments in the laboratory, lead him to the belief that the method is impracticable. Thus, before one reached the height of ten miles - where there is greatly increased conductivity - the electricity would have deserted the terminal raised to that height and would have flowed to the ground, instead of taking the path of the air to the distant station! In the dark, one can see the reason for the diminished length; for luminous discharges are noted between the high tension apparatus and the floor of the room. The inductive effect is so great that sparks can be drawn from the brick walls and the neighboring gas pipes! The time when the upper regions of the air will be thus used commercially seems therefore to Prof. Trowbridge far distant.

As we have stated above, Prof. Trowbridge’s hypothesis is not without objections. Thus, we may ask, how according to that theory, can the fact be accounted for that auroras have been observed within but a hundred yards of the surface of the earth, where there could be no possible adequate rarefaction of the air? Still the hypothesis is interesting and, at least, si non e vero e ben trovato.

Apropos of the suggestion of utilizing the upper strata of the atmosphere as a current conductor, we are reminded by some of our readers of the fact that the idea was put forth some twenty-five years ago by Mr. S. J. M. Bear for telegraph work. And now, Chicago, not to be outdone, has a claimant to the same region, in the person of Mr. Archibald J. Robertson, who claims to have covered the idea in a patent granted to him in 1892. From what he says, it looks as though we shall presently learn of a suit for infringement brought against Mr. Tesla. If a Chicago man can lay claim to giving the main idea of Cyrano de Bergerac to Rostand, why may not another from the same city of unlimited area and ideas claim all the upper atmosphere and its attributes as his own? To avoid strife and the establishment of a grinding monopoly in the future we would suggest that all claims in those regions be now staked and filed in a Government Air Bureau specially organized by Dr. Cleveland Abbe for that purpose, and to be called the Government Rarefied Air Office, with regulations patterned after those of the present Land Office. This might at once mitigate the coming wars with squatters and interlopers.