Light Without Heat Perfected by Tesla

The Great Inventor Tells the Sunday World About His New Vibratory Vacuum-Tube Lamp.

MAKES A WHITE LIGHT AS BRIGHT AS SUNSHINE.

Not since Edison, in 1879, proclaimed the success of his efforts in subdividing the electric current, making incandescent electric lighting possible, has there been so important an announcement in the electrical world as that made last week by Mr. Nikola Tesla that the advances made by him in vacuum tube lighting had reached a point that assured complete commercial success.

The results of Tesla's work in the field of currents of high frequency were first made known to the public in his now famous London lecture of 1891. In 1892 he gave the same lecture with a large number of brilliant experiments before the National Electric Light Association at St. Louis.

The results then exhibited were startling and aroused the most intense interest. At that time, however, Mr. Tesla himself admitted that his work was not yet commercial. Few even of his stanchest adherents believed it ever would be.

Now, after four years of hard work, and having been delayed by the fire which destroyed his laboratory and much of his most valuable apparatus, the great inventor is jubilant over the measure of success achieved, and has broken the long silence which he has persistently maintained in regard to the progress of his work.

LIGHT WITHOUT HEAT.

Mr. Tesla said to a Sunday World reporter:

"Four years ago when the first public announcements were made of the results of my work in vacuum tube lighting, I found few people who would admit that I had anything more than an interesting laboratory experiment. My visitors all said, 'What beautiful effects!' and in the next breath, 'How utterly uncommercial.'"

"To-day I believe, not that the ultimate is attained, but that I have already produced a thoroughly practical and commercial method of vacuum tube lighting, vastly more economical than either the arc or incandescent systems and which will be a marked advance over the present methods.

"I have never wavered in my belief in the ultimate, and acknowledge a measure of satisfaction now that I know all obstacles have been overcome."

What this statement means can only be appreciated by those who fully understand the natural reticence of Mr. Tesla and his persistent refusal to make any claims or reports of what he has done.

LITTLE ENERGY LOST.

Continuing Mr. Tesla said:

"There has been little change in the apparatus I now use compared with that I displayed at St. Louis. The basic principles are the same. I have simply made improvements and marked advances.

"I found the causes of loss of energy and have largely overcome them. Already I can deliver 10 per cent. of the initial energy in a pure white light. This is three times the efficiency of an ordinary incandescent lamp."

"Is your vibrator the same as the one which you showed at St. Louis?"

"No, I have long since discarded the vibrator. I found it impossible to produce one which would last more than a few hours, so I found a better way, and now use no vibrator at all."

"But, Mr. Tesla," the reporter said, "how can I explain to a layman just how you start the ether in your exhausted bulbs into such rapid vibrations and produce this light with no mechanical vibrator?"

"You can't explain it. I don't know that I could. You might say," said Mr. Tesla laughingly, "that it is the music of the celestial spheres.

"There is no direct connection between my conducting copper wires and the interior of the exhausted bulbs. The current passes through the glass. There is no vibrator, no mechanism."

Asked what vibratory speed were now attainable Mr. Tesla replied:

"About 6,000,000 a second now. In a short time I expect to produce 50,000,000 per second."

"How do you measure them, Mr. Tesla?"

MEASURED BY THE EAR.

"In two ways, one of which I will not describe. But the second is by my ear only. Taking one of these little bulbs I can distinguish the periods of vibration almost as accurately as the musician can distinguish the tones of the scale from his tuning fork."

The light produced by Tesla's latest tubes is pure white, possessing all the visible qualities of sunlight. Moreover, according to the great inventor, it has all the purifying qualities of sunlight, and a room, well ventilated, would be equally healthy to live in whether lighted by one or the other.

When it is remembered that in gas lighting there is less than 1 per cent. efficiency, in incandescent electric lighting less than 3 per cent., and that Tesla can already show 10 per cent., with a promise of getting a great deal more, the importance of his discovery in the commercial world is apparent.

APPARATUS VERY SIMPLE.

No expensive or complicated apparatus is needed. A simple coil is provided which transforms the ordinary low-tension current, making it available for use almost anywhere.

A particularly attractive feature of the new light is that the new bulbs, once exhausted, have a practically unlimited life. Mr. Tesla has some which have been in use in his laboratory almost continuously for four years, and are still burning with undiminished brilliance and consuming no more energy than when first lighted.

One little bulb now burning in the laboratory is sufficient for a parlor of ordinary size, giving out as much light as an arc lamp, glowing steadily without any wavering, and consuming but a fraction of the energy.

With the success of this vacuum bulb lighting system practically assured, the tireless inventor has not relaxed his efforts, and is working harder than ever.

TO UTILIZE EARTH CURRENTS.

Next in his mind is the perfection of the oscillator, and after this, nothing less than telegraphy and telephony without wires.

"Do you actually believe that is possible?" Tesla was asked.

"I more than believe it. I am sure of it. Further than that, I believe that with this grand force nothing is impossible. Even the most optimistic or visionary dreamer would fail to predict the accomplishments of the next decade."