camera, a modification of Albers-Schönberg's Kompressionsblende.

To secure more contrast, though at the expense of some detail, the dry plate or film may be sandwiched between really fine-grained calcium tungstate screens.

A good induction coil is at present the only available instrument capable of furnishing the requisite electrical energy.

The tube must be able to keep its vacuum. A critical tube for a medium-size chest should give a skiametric reading of W. 6 or its equivalent.

The lowest tube that will do the work is the best for the purpose.

1

Editorial.

HIGH FREQUENCY CURRENTS.

The differences between the various electric modalities are simply differences of degree, yet so widely do the many manifestations of electric energy differ in their effect, from physiologic to therapeutic, that we have been accustomed to speak of different kinds of electricity, galvanic, faradic, static, etc., therefore, although simply varying manifestations of electric power and equally obedient to the great law of Ohm, they are practically and for working purposes quite different in kind. In high frequency currents we have still other manifestations of electric force, and just as faradic currents distinctly differ in tension and therefore in effect, according to the construction and nature of the coil, so high frequency currents differ according to the nature of the initia! force inducing them and the manner of their discharge. High frequency currents are obtained by a step-up process. The rapidity of the oscillations of the static wave current are sufficiently high to entitle it to be called a current of high frequency.

The hyper-static current, so-called, which is from a form of Tesla coil, greatly exceeds the former in the rapidity of its oscillations, just as the D'Arsonval current exceeds the hyperstatic. The remarkable and distinguishing characteristics of high frequency currents are that the higher we go in the stepup process, the less marked are the motor and sensory manifestations. It has been shown that beyond 500 excitations per second the phenomena of muscular contractions become less and less until none can be produced. And yet notwithstanding this absence of sensory effect the remarkable spectacle of a glowing incandescent lamp is presented, as the current passes through it, having previously passed unfelt through the human body. The physiological effects produced by this painless and apparently innocuous manifestation of electric force have been made the subject of much patient investigation and the general results arrived at are that besides a general modification of nutrition, there is a decided increase in arterial tension, a greater elimination of CO, and an increase in the production of heat.

As concerns the therapeutic range of the two forms of high frequency apparatus now in more or less popular use, experience confirms what from the nature of the two, one would naturally infer: the apparatus generating a current of considerable magnitude but lower tension (D'Arsonval), influences metabolism and its effects are deep-seated and wide-spread; the apparatus generating a current of little, if any, magnitude but higher tension (hyperstatic), seems to exert little, if any, constitutional effects. These are mainly local, and its usefulness is especially seen in the various superficial but benign skin affections. But high frequency and high potential combined with appreciable magnitude are potent therapeutic factors, producing results that are distinctly constitutional and deserve the most careful investigation.

Miscellaneous Abstracts.

A CASE OF CARCINOMA TREATED WITH THE X-RAYS By G. B. Batten, Archives of the Roentgen Ray, February, 1904.

The patient, a woman aged 56 years, had her left breast and axillary glands removed by Jonathan Hutchinson, Jr., in November, 1900, for what was demonstrated by microscopical examination to be "typical scirrhous" cancer. During the time intervening between that date and September, 1902, six recurrent nodules had successively appeared and had been excised by the same surgeon. Another nodule appeared in November, 1902, which was subjected to X-radiance, instead of the knife. The tube was of "medium hardness," anticathode located six inches from the patient's skin. Eight treatments of ten minutes duration each were given in fifteen days, and the pain began to diminish after the second application, disappearing entirely before the fifteen days were up. The applications were then suspended for thirteen days and three more of fifteen minutes duration each were given during the six succeeding days, when dermatitis appeared and they were suspended again. A month later two treatments of twelve and a half minutes each were administered.

Three months later the nodule and all signs of the disease had entirely disappeared and patient continued in good health

until four months after, when she died from septicaemia caused by the bite of an insect. The portion of skin and underlying tissue where the recurrent nodule, which had disappeared under X-radiance, had been located, was excised and the microscopic findings by Dr. James Galloway are of such interest that they are appended in full, as follows:

"I. The epithelium is thin, but the different layers are recognizable with little difficulty.

"The stratum mucosum consists of two or three layers; the lowest layer is arranged in an irregularly 'palisade' order on the underlying cutis, but this arrangement is not nearly so perfect as that seen in the normal skin. The cells of the stratum mucosum seem to be of nearly normal type. There is an imperfect stratum granulosum; its cells are few in number and sparsely scattered over the underlying epithelium. Sometimes considerable distances separate the adjacent cells, as seen in section; but this layer seems to be sufficient from the functional point of view to permit of the formation of a complete stratum corneum. The cells of the stratum corneum are completely keratinized, and although the cells are more loosely arranged than in the normal skin, it forms a complete horny covering.

"The interpapillary processes of epithelium are practically non-existent, as the papillæ of the cutis have nearly disappeared.

"Remnants of the skin appendages are recognizable in places. "2. The cutis consists of bands of connective tissue closely compacted, with comparatively few connective-tissue cell nuclei, so that the aspect of scar tissue is presented. The papillæ are nearly completely gone, the upper edge of the cutis being only slightly undulating; only here and there are anything like true papillæ to be observed. Foci of leucocytic infiltration may be seen usually towards the upper surface of the cutis, giving evidence of inflammatory reaction; but these are not numerous, and are of small size. No special widening of the vessels of the cutis is noticeable.

"No signs of malignant epithelial growth are noted throughout the extent of this section.

"The general appearance of this specimen is that of skin which has undergone atrophic change as the result of inflammation of low degree."

COMMUNICATION REGARDING THE TREATMENT

WITH LIGHT AFTER DREYER.

Prof. A. Neisser and Dr. Halberstaedter, Deutsche Medizin, Wochenschr. 18 Feb., 1904

In this paper Neisser, the well-known dermatologist and genito-urinary surgeon of the University of Breslau, takes up the study of light, thus giving a new impetus to further investigations in this field. He speaks first of the influence of light on the skin, giving a review of the present knowledge on this topic. He also includes the question of the bactericidal power of light ray, and in this connection mentions the fact that the penetrability of rays varies inversely as its bactericidal power; in other words the most actively bactericidal rays of the blue end of the spectrum possess only a very limited power of penetrating into the deeper parts of the body. For this reason Dreyer of Copenhagen conceived the happy idea of influencing artificially the tissues in such a manner that they become just as sensitive to the green, yellow and red rays as they normally are to the ultraviolet. In the same manner as a photographer's plate is made sensitive, so did Dreyer conceive that the body tissues might be influenced by using Erythrosin (1:4000.). The result with cultures proved his theory perfectly. By using a 26 ampere lamp he saw that bacteria on the insensitized plate were killed only in the ultraviolet region, while the other parts of the spectrum showed no influence of the light. On the "sensitized" plate the effect was seen not only in the violet, but also in the yellow-orange region, viz., destruction of bacteria. Experiments on frogs as well as on guinea pigs were also positive. From these facts we may therefore conclude that a therapeutic effect of light is obtainable also in deep-seated lesions of the body and according to Neisser it is not fluorescence.

Halberstaedter, Neisser's assistant, repeated Dreyer's experiments, using the method practically in twenty-five cases, viz., of lupus, scrofuloderma, tuberculous glands, spina ventosa, etc. He used I per cent to I-10 per cent sol. Erythrosin in 0.85 salt water. The injections were made as deep as desired and from two to five hours later light was used for 15 to 20 minutes, or even longer if necrosis was expected as in carcinoma.

It is a great field that has been opened by these studies, and there is no doubt that we shall hear more within the next year

or so.