Eberhart's Manual of High Frequency Currents
Noble M. Eberhart, M.D., Ph.D., D.C.L., 1911
Various Forms of Vacuum Tubes; Effects of Different Vacua;
Insulated Tubes; Fixed and Adjustable Socket Handles.
Various forms of Tubes. The vacuum tubes used in high frequency
work have been made in almost every conceivable form to enable them to be applied to
various parts of the body. The vacuum of these tubes varies from one-five hundredth
of an atmosphere up to that possessed by the X-ray, one one-millionth. The color
which appears in the tube varies according to the degree of vacuum; thus a low vacuum will
produce a reddish color or glow in the tube; one of medium or slightly above medium
vacuum, a blue color; and a high vacuum a white appearance.
Strong says, As the exhaustion proceeds from one-five
hundredth to one-ten thousandth of an atmosphere, the disks become thicker and the
striations fewer, and the color changes from a rose-pink to violet, blue (one
one-thousandth), blue-white, and finally to a dense yellow-white. A low X-ray vacuum
would be about one one-hundred thousandth of an atmosphere.
Besides the degree of vacuum, the light is also supposed to
be influenced by the kind of gas remaining in the tube, and some authorities claim that
there is a direct analogy between the rapidity of the oscillations at the spark gap and
the color of light in the tube. As the lowest number of vibrations producing the
color red is 450 billions per second and the highest violet 750 billions, this
analogy seems improbable.
The low vacuum tubes give off more heat, while the high ones
give some chemical (ultra-violet) rays and if very high, X-rays.
The red or red-pink vacuum, besides
giving off more heat, is sedative and useful in painful conditions and in acute diseases
The medium, blue, or blue-white vacuum gives
off some chemical rays, and is more appropriate in chronic conditions. It is often
employed where the white vacuum would really be indicated, as this contains not only blue
and violet, but also some ultra-violet rays. All chronic ailments, where the
vitality is impaired, skin diseases, indolent ulcers, etc., call for the employment of the
white or blue-white tube.
Fig. 18 - Interrupterless Transformer,
with Resonator Employed in Giving Auto-condensation.
Fig. 19 - Portable Outfits.
Fig. 20 - Tubes and Handles.[numbered]
Fig. 21 - Condenser electrode. Insulated Tubes.[numbered]
Much of the foregoing is more theoretical than it is
practical and I have finally come to the conclusion that a medium vacuum electrode (purple
tinge) answers all practical purposes, and this is what I am now using.
Vacuum tubes are ordinarily made in a single chamber, the
tube fitting into the socket of a handle that is used for all the different forms.
Some tubes have a leading-in wire and others, instead of having a single chamber in the
tube, have the vacuum divided into two chambers the size of the circumference of the tube,
connected by a small tube, possibly the size of a small pencil, and surrounded by a
chamber that is not a vacuum. These latter are known as insulated tubes.
The tubes used most frequently are shown in Fig. 20.
No. 1 is the body tube, which is used also in treating face and scalp. No. 2 is the
rectal tube; 3, vaginal; 4, nasal; 5, urethral or aural; 6, throat. In place
of No. 1, No. 11, Fig. 21 will be found equally useful and in some instances superior on
account of the ridges around the depression, enabling it to be used where it would be
difficult to place the body tube.
Fig. 22 - Various types of Tubes.
Fig. 23 - Vacuum Tubes
Insulated Tubes. The advantage of the insulated tube which I
have been in the habit of calling the Titus tube, because I believe it was first designed
by Dr. Titus, is that with this tube the current may be introduced without loss into an
orifice of the body. Take a plain vacuum tube and attach to the current and when it
is lighted up, surround it with the thumb and forefinger and it will be observed that
there is no light beyond the point of contact. It stands to reason, therefore, that
if such a tube were introduced, for instance into the rectum, the point of contact with
the body would draw off much of the current and the surface within the body would receive
but little treatment. For this reason with the insulated tube the opening of the
orifice comes in contact with the non-vacuum part of the tube and the end of the tube
where the vacuum exists thus conveys all of the current in at the desired point.
I have been taken to task for my statement above, on the
ground that contact with the encircling finger possesses no capacity. It simulates,
however, the conditions of certain orificial treatments and after trying the experiment
referred to, I am sure the physician will resort to the use of insulated tubes for rectal
and other orificial work.
The principal forms of insulated tubes in use are shown in
Fig. 21. No. 7 is for the ear; 8, rectal, or prostatic; 9, post-nasal; 10, for
vagina or uterus; 11, prostatic or for general surface use; 12. Urethral or aural; 13,
The Adjustable Socket Handle. The ordinary
holder for high frequency tubes consists of a straight handle with a metal socket into
which the tube is received as shown in Fig. 20. This is suitable for holding
electrodes that are applied to the surfaces of the body, but for most conditions I prefer
a handle with a movable or adjustable socket. Fig. 20. This socket may be
placed at any angle to the handle that may be desired and with a thumb screw made secure
at this point necessary. The advantage of this will be discussed in detail in
Chapter VII., when considering the special technique for various portions of the body.
The latest type of my adjustable handle is shown in Fig.
24. It is of spring steel and accommodates tubes of varying diameters.
Authors Spatulate Tubes. I have recently
designed the tubes shown in Fig. 27. They end in a flattened spatulate
extremity. In the body tube the end is at an angle with the main tube, thus making
it much handier to use than the regulation type of body electrode.
Fig. 24 - Authors Latest Adjustable Handle.
The vaginal, prostatic and rectal tubes are similar in shape,
but are straight. They vary only in size and are made both plain and insulated.
Fig. 25 - A Neat Combination of High Frequency and X-Ray.
The physician who has been using vaginal and prostatic
tubes will readily perceive the advantages of the larger flat surface. Either of
these tubes will be found quite satisfactory for surface applications.
Fig. 26 - A Compact Portable Outfit.
Fig. 27 - Authors New Spatulate Tubes.
Fig. 27a - Portable Outfit.