(taken from his ©1927 book "Light Therapeutics")
The Incandescent Light
When the incandescent light bath was first constructed and introduced into
therapeutics by the author in 1891, no adequate conception could be formed
of the large place which this curative agent was destined to fill in the
modern treatment of disease. Since that time the electric-light bath in
various forms has found its way into almost all of the leading hospitals
of the world. Hundreds of establishments, especially devoted to the employment
of light as a therapeutic agent, have been opened, more particularly in
Germany, and hundreds of physicians have become acquainted with the remarkable
healing properties of this agent. Phototherapy or light-therapy has come
to occupy a large field in therapeutics, and the number of papers, treatises
and reports dealing with the subject has multiplied to an astonishing extent.
The list of the maladies which yield to the influence of light is daily
increasing, although including already quite a large proportion of the
chronic ailments encountered in clinical practice.
Freund, of Germany, has been among the most active in developing the therapeutics
of light. He employs the simple incandescent light apparatus with or without
color filters in the treatment of superficial skin affections for neuralgia,
myalgia, etc. The appearance of marked hyperemia and slight perspiration
indicates that the treatment should be for the time suspended. Painful
effusions of the joints and muscles and rheumatic pains are quickly relieved.
This treatment quickens the re absorption of serous joint exudations and
dropsical accumulations. Rheumatic patients who can hardly stand before
the treatment are able to walk without pain after it. Complete cure is
effected when the treatment is prolonged and combined with other suitable
Exposure of superficial inflammations and suppurations to powerful incandescent
lamps brings strikingly good results (Freund). This treatment is especially
beneficial in cases of acne vulgaris, ulcerating X-ray dermatitis, ulcerating
lupus, and scrofulous neck abscesses. The duration of the exposure
was thirty minutes with the disease part as close as possible to the source
Dworetzky, Kessler, Turner, Minin and others testify to the value of local
treatment with the electric incandescent light in such painful affections
as lumbago, rheumatism, cephalalgia, odontalgia, pleurisy, and pains in
the chest following influenza; also in the absorption of exudates in cases
of rheumatism, pleurisy, peritonitis, and gonorrheal arthritis. They even
report good results in the absorption of effusions of blood, both retinal
and subcutaneous and also subperitoneal. Ulcerations, eczema, lupus, and
other skin affections, and venereal and syphilitic effusions heal more
rapidly under the influence of local incandescent light.
Rockwell reported excellent results in the relief of pain dependent on
congestive and inflammatory conditions even though deep-seated, and has
found the light treatment to be far more efficacious in neuritis than any
other therapeutic measure.
In addition to its power to relieve high blood pressure and pain, its thermic
properties have a stimulant effect on metabolism, and its efficacy in increasing
the hemoglobin-carrying power of the red cells renders the incandescent
light valuable in a variety of conditions.
Schamberg thinks that light would doubtless have been more used as an auxiliary
therapeutic measure had not the suddenly established reputation of the
X-ray thrown the milder-acting light rays into the shadow. The X-ray produces
important and profound changes in the cells and tissues, and when judiciously
applied becomes a wonderful therapeutic weapon. But it is also capable
of doing great harm, even irremediable, when improperly used. On the other
hand, light energy, although much slower and milder in its effect, is perfectly
Effects of the Incandescent Electric-Light Bath
During the time which has elapsed since its first employment (1891), this
bath has been used under the author's general supervision in more than
fifty thousand cases, aggregating several hundred thousand applications.
At first its chief value was attributed to its eliminative effects, but
deeper study of the subject has/convinced the author that its chief value
rests in its influence
upon the circulation. Under the influence of the general electric-light
bath, the skin is filled with blood. The stimulation of the sweat glands
is incidental. The perspiration has some value through its influence
upon general metabolism, but the amount of toxic matters carried out
through the skin is small.
The complete filling of the skin with blood removes the disabling congestion
of the liver, stomach, spleen and other internal parts. This relief is
rendered more or less permanent by the fixation of the blood in the skin
effected by the cold application which always follows the electric-light
bath as well as other general heating measures. The active vascular dilatation
following this cold application is of much longer duration than that
resulting from the application of heat alone; thus a more or less durable
effect is produced.
By a daily repetition of this procedure, normal conditions are gradually
restored. The circulation of the skin becomes more and more active, and
the amount of blood in the over-distended internal organs is diminished.
The enlarged liver and enlarged spleen contract, the congested sympathetic
nerve centers return to the normal state, and the vital resistance of
the tissues is increased. Catarrhs of the stomach and intestines and
biliary passages disappear, the digestive secretions acquire their normal
characteristics, the liver, adrenals, and lymphatic glands and other
poison-destroying organs resume their functions. The various symptoms
of autointoxication disappear; the skin reacquires its natural elasticity
and color, and the patient gradually returns to a normal state.
For producing the effects described, long applications are seldom necessary.
Three to six minutes are ordinarily sufficient. The duration of the bath
need be only enough to produce moistening of the skin from perspiration.
In certain classes of cases, longer baths are needed. This is especially
true of obesity, rheumatism, gout, and in diabetics who are strong and
not emaciated. In these cases it is necessary to continue the bath sufficiently
long to produce an elevation of temperature, so as to stimulate oxidation
of the protein wastes. For this purpose the duration of the bath should
be fifteen to thirty minutes, or until the temperature taken in the mouth
reaches 100° to 100.5;° F. It is better, when possible, to take
the temperature per rectum.
The Incandescent Light as a Source of Infra-Red Rays
As a source of heat rays, the incandescent light is not excelled either
for efficiency or convenience as a measure for therapeutic use. It
has rapidly won its way to popular favor and has rendered obsolete
Russian, vapor and other forms of heating baths which had been in use
Therapeutic Applications of the Incandescent Light
During the thirty-six years which have elapsed since the writer constructed
the first electric-light bath, he has found the field of application
for this convenient thermic measure continually widening. This device
has, indeed, proved to be of far greater value in the treatment of
a large variety of maladies than any other means of applying heat,
excepting water, and admits of more general employment than the ordinary
Turkish, Russian, vapor, or hot-air baths. One reason of this is the
convenience and rapidity with which the degree of heat may be graduated
by turning on or off one or more groups of lamps, the amount of heat
being thus rendered absolutely and instantly controllable, since the
source of heat relied upon is the incandescent filaments of the lamps
rather than a heated atmosphere. The instant the lamp is turned off,
the heat which had previously been emitted is withdrawn from operation.
If additional heat is required, the desired number of lamps may be
turned on, and become instantly operative. Still more perfect regulation
be effected by means of a simple rheostat.
Another reason for the more universal utility of the incandescent-light
bath is the fact that when properly applied, its effects are highly
tonic in character. A short application of the bath at full intensity
time just sufficient to induce strong heating of the skin without provoking
profuse perspiration, is a most effective means of cutaneous stimulation.
The tonic effects of such an application may be still further intensified
following the bath with a cold spray or other cold application, thus
producing a revulsive effect of the most agreeable and effective character.
The intense heating of the skin prepares the way for the cold application,
without at the same time so overheating and relaxing the blood-vessels
as to render recovery of the tone of the cutaneous tissues so tardy as
to involve the risk of exhausting the patient too greatly or exposing
him to the liability of taking cold. In the experiments referred to,
the amount of perspiration produced in the electric-light bath was found
to be double that produced in the Turkish bath. The body temperature
is also raised much more rapidly in the electric-light bath than in any
other form of hot bath, because the rays of radiant energy pass through
the skin and reach the interior of the body at once, whereas in the ordinary
hot bath the heat penetrates the tissues very slowly, and only reaches
a small distance beneath the surface.
The electric-light bath is especially valuable in renal disease and in
diabetes, in which prolonged sweating measures can not usually be employed
without more or less risk. The penetrating nature of the heat of the
electric-light bath stimulates oxidation of the residual tissues, and
thus hastens the disappearance of redundant fat in obesity. In dropsy,
associated with either cardiac or renal disease, in the toxemia of
chronic dyspepsia, and in all conditions for which general and local applications
of heat are applicable, the electric-light bath stands pre-eminent.
In rheumatic and anemic patients, and in all cases where the heat-making
capacity is small, the electric-light bath serves an exceedingly useful
purpose in preparing the skin for cold applications by storing up in
it a supply of heat. And it serves a useful purpose in this way, not
only in preparing the patient for tonic applications of water, but as
a means of producing most excellent revulsive effects. For pure revulsive
effects, only the circulatory reaction is desired, it being, in fact,
necessary to suppress thermic reaction together. Hence, the duration
of cold applications which follow hot applications should be such asexactly
to neutralize the heat which has been absorbed by the skin in the previous
hot application. The electric-light bath is superior to all others in
the treatment of chronic rheumatism and all maladies dependent upon chronic
toxemia, owing to its ability to elevate body temperature while at the
same time producing vigorous cutaneous activity. The elevated temperature
stimulates the oxidation of protein wastes, and augments vital combustions,
while the increased skin activity carries off the waste products prepared
Recent physiological experiments have shown that the elevated temperature
in febrile conditions is one of the methods by which Nature combats the
causes of disease, or neutralizes some of the morbid conditions resulting
from disease. The physiological effects of the electric-light bath may
exercise in many cases a strongly curative influence by the elevation.of
the body temperature, thereby enabling it to produce antitoxins, or to
render more effective the curative efforts instituted by the vis
As a prophylactic, this bath also possesses a high value, especially
for persons who live a sedentary life, as teachers, doctors, lawyers,
preachers, judges, and professional men generally, and to a still greater
degree for the majority of women, as it is the best substitute for muscular
The hygienic value of the sweating bath is certainly scarcely yet appreciated
by the majority of civilized men and women. This cannot be said of the
Finns, however; for in Finland every house has connected with it a bath-house
with conveniences for producing vigorous perspiration. Indeed, the author,
while on a visit to Copenhagen, was told by an intelligent Finnish gentleman
that it is the custom in his country for a young man anticipating matrimony
to build as a foundation for his future home, first of all, a sweat-house.
A vast multitude of city dwellers in civilized countries are suffering
tortures from disease in various forms, and dying prematurely, because
of the neglect of that important provision in the injunction of the Almighty
to Adam, "By the sweat of thy brow shalt thou eat thy bread." Indeed,
the neglect to sweat is one of many prolific causes of disease in the conditions
of civilized life. A modern writer has very sagaciously suggested that
the chief difference between the savage and
man is in the way he sweats. The savage sweats his brow in earning
his bread, and taxes his brain but little; the civilized man earns
his bread by the sweat of his brain, but seldom sweats his brow.
Sweating by the electric-light bath, while not a complete substitute
for the sweating produced by exercise, certainly comes nearer to being
so than any other sweating process ; and when followed by some vigorous
cold application, as the cold shower, possesses a hygienic value which
cannot be overestimated.
Cautions and Contraindications
The electric light acts far more quickly than any other heating procedure
for the reason that its rays instantly penetrate deep into the tissues
an inch or more, and thus the body temperature is quickly raised. It
is well to take the patient's temperature just before the bath and immediately
after, and even during the bath if it is much prolonged. In a prolonged
bath the body temperature may rise to 103° F. or more in a few minutes
(15 to 20 minutes). The general light bath should not be given to a patient
who is in a febrile condition.
Intense heat is depressing, especially to the heart; hence it is necessary
to protect the heart during the application by means of an ice bag or
a cool compress.
The electric-light bath is too exciting for certain forms of skin diseases,
especially when the eruption is moist and when intense itching or burning
Technique of the Incandescent Light Bath
In the use of the incandescent light bath, either cabinet or photophore,
the following points should be borne in mind:
1. The application is thermic in character, the amount of ultra-violet
rays present being quite insignificant.
2. The purpose of the application is to heat not only the skin, but
the sub-dermic tissues.
3. The intensity of the application is limited
the tolerance of heat by the skin. When the temperature of the cutaneous
nerves is raised above 115°, pain is experienced and the limit of
tolerance is reached at 120° F. By cooling the skin by means of
a current of air, the intensity of the application may be very greatly
increased. Sonne has shown that the rate of radiation of heat from
skin in cool air is increased to five times the normal. A current of
air produced by an electric fan may be used in general applications
with the light cabinet bath or, in local applications, with the photophore.
4. A glass of water should be taken just before the bath and after.
5. Care should be taken to see that the feet are warm.
6. Care should be taken to avoid overheating.
7. It is not necessary to cool the patient's head in the cabinet bath
except in giving long sweating baths.
8. In general, prolonged sweating should be avoided except in certain
cases of rheumatism and obesity. In such cases, the bath should be sufficiently
prolonged to produce a rise of temperature of one or two degrees.
9. Applications of radiant heat should always be followed by a cooling
procedure adapted to the case. Cabinet baths require a cool or tepid
shower, a neutral bath, or cool towel rub or wet sheet rub.