second beat is shown by the galvanometer to be a ventricular extrasystole. Coupling is a danger-signal—an indication that the patient's extreme limit of tolerance for digitalis has been reached.

So far as my personal experience with digitalis has been concerned, I have had occasion many times to confirm Mackenzie's views. There is abundant evidence nowadays to show that the indication for digitalis is not merely a dilated heart, but a dilated, fibrillating heart. And when digitalis is indicated the fresh tincture of good English leaves works perfectly, and is much to be preferred to all the host of proprietary hypodermics, which are generally used in the wrong cases and too often produce little but multiple abscesses.

Of the rarer anomalies of cardiac action, like auricular flutter, where the auricle beats 250 or 300 a minute, and sino-auricular block, where there are sudden vagal changes in a regular rate, it would perhaps be best not to speak at confusing length in an informal paper, and I conclude with some comments on the more important features of auriculo-ventricular block.

To understand blocking it is not necessary to go to a terrifying depth into the physiology of the heart. All one has to remember is that the contractile wave, starting at the top of the right auricle and running thence down both auricles, reaches the ventricles through one special bundle of muscle in the auriculo-ventricular region. This bundle is called the bundle of His. When the bundle of His is inflamed, degenerated, pressed upon by a gumma or other tumor, or even, as sometimes happens, only temporarily crippled by acute toxæmias, it loses to a greater or less degree its conductivity. Instead of the contraction wave getting through the heart in 0.12 or 0.16 or 0.18 second, the time is prolonged to 0.20 or 0.25, or even more than 0.30. This prolongation of the a-c interval, of which we have already spoken at some length, is the first stage of blocking. Next comes the stage of "dropped beats," "partial block," where, after a certain number of heart-beats, the His bundle is momentarily exhausted and the ventricular beat falls out. In its earliest stage this is a form of "intermittence" which without a tracing might perhaps be confused with extrasystoles a dangerous mistake.

Sometimes a relatively regular partial block occurs and the ventricle beats with every second, third, or fourth auricular beat. In Fig. 15 the ventricle beats with every third auricular beat. Partial block,

however, is generally an unstable condition, and tends often to "complete block" (Stokes-Adams's disease), in which the auricles beat with one rhythm, and the ventricles with another entirely different.

While a blocked pulse may evidently, in the nature of the conditions, be fast or slow, regular or irregular, it is apt to be extremely slow and quite regular (bradycardia). Of course, bradycardia may be physiological, with a clean-cut v, a, c jugular sequence for every arterial beat; but it ought always to be viewed with suspicion, and the patient carefully examined by graphic methods.

This is essential not only from the point of view of the man who wants to get his diagnosis correctly, but for purposes of treatment also; for digitalis is a dangerous drug in heart-block, and should be used with extreme circumspection, if at all.

It not infrequently happens that in suspected blocking of the ventricles one may note in a good light, by the naked eye, the venous pulsations, and by controlling them with the finger on the apex-beat or the carotid form a shrewd estimate of what is going forward, but this is mere guesswork, subject to many sources of error, and always to be verified with an instrument. One of the commonest errors among inexperienced students is the mistaking for a multiple venous pulse the one or more recoil waves of a stiff carotid. The tracing in Fig. 16 was from a patient of this kind in whom block was suspected. The double tracing showed the real state of affairs

at once.

PHYSICAL AND ELECTRICAL THERAPEUTICS IN

GENERAL PRACTICE

BY GEORGE B. BATTEN, M.D.

London

As I have used these methods for over seventeen years, I thought that the results of my experience might be interesting and, I hope, useful to others who, like myself, are engaged in the general practice of medicine. I cannot to-day attempt to review the whole subject of physical and electrical therapeutics, which, of course, includes balneotherapy, hydrotherapy, ranging from the giving of an enema to applying a Nauheim bath, and also includes massage, breathing exercises, etc. I intend, therefore, to confine myself to the same limits as I did in a paper on "Heat, Light, X-ray Electrotherapeutics," which I read before the British Electrotherapeutic Society in March, 1903, just eleven years ago. This list made for that paper will show you how I then subdivided it, and I intend more or less to follow the same classification now. I have a new list here for to-day.

I will try to be as short and as practical as I can, and will demonstrate the methods as far as possible.

1. Cold, produced by Leiter's tubes, ice-caps, and ethyl chloride spray, is, of course, useful for certain inflammations, headaches, and neuralgias.

Intense cold, produced by solid carbonic oxide, has, during the last few years, been employed most successfully for a variety of complaints. I had some X-ray warts on my hand treated and cured by CO2 on the first day it was demonstrated in England by Dr. Reg. Morton. The method I use is a very simple one, some of which was suggested by our friend, Dr. H. G. Clitherow. Take a piece of thin blotting-paper, roll it up in a cylinder over a rod or test-tube, pinch together one end of it and hold it over opening of the liquid CO2 bottle; when the snow has collected, unroll blotting-paper and drop snow into an ordinary penny funnel with a spout of appropriate size, ram this tight into the spout with a weighted wire, then push it out

VOL. I. Ser. 25-3

33

the reverse way, and we have a conical rod of solid CO2; cut or rasp this into the size wanted and apply to part to be treated for proper length of time and with proper pressure.

This substance is most successfully used for treatment of nævi, moles, warts, lupus, rodent ulcer, also of trachoma and pannus. It is about the only successful method of removing warts and excrescences that arise or have arisen on the hands of X-ray workers. It is necessary to freeze just through the thickness of the growth; in about a fortnight the frozen part is shed off from the underlying unfrozen parts. About forty seconds are required for a nævus, rather longer for a wart, and fifteen seconds for a thin X-ray wart.

There is another method of applying CO2 snow; it is to put the loose snow into a measure glass, pour a little acetone on it, which makes a viscous liquid with it, and paint this on to the skin with a brush for about five seconds. This is specially useful for large areas such as occur in nævus flammeus (i.e., port-wine stains) and lupus erythematosus. Don't do the same spot twice at the same sitting, or a slough may form.

2. Heat. (a) Electrocautery. I use the ordinary electrocautery from either 4 to 6 volts accumulators. More frequently I use the electrocautery from a step-down transformer direct from the mains; a voltage of 4 to 6 is best. The electrocautery is, as you know, very useful in treatment of many nasal complaints-in granular pharyngitis, for nævi, moles, warts, etc. Warts and small moles can be removed in one sitting by freezing by ethyl chloride and then burning off with electrocautery; wait until all the liquid ethyl chloride has evaporated before turning on the current, or it will catch fire. A practical point is to burn fairly deeply and to wipe off the wart, or tell the patient to do so at the end of twenty-four or thirty-six hours, not longer. A line of separation, due to the burn, occurs, I believe, in the prickle-cell layer of the skin, and if the wart is taken off while this separation blister lasts it is cured; otherwise it may harden down and commence to grow again. I have found this method the only good one for those troublesome and painful wart corns that form on the feet and are the despair of ordinary chiropodists. Several applications at intervals are sometimes necessary to cure these.

b. Heat from wires. Air blown over wires heated by electric current in the hot-air douches are very comforting in certain painful

affections; also the now much advertised electrotherms or mats heated by concealed electric wires.

c. Heat from arc lamps. I use an ordinary angold alternating arc lamp, but, instead of using it enclosed in glass, I project the rays by a parabolic mirror on to whatever part of the patient is desired; this is better than using any condensing lens, for the lens intercepts a great number of the heat and violet light rays, and an arc lamp gives off more penetrating rays than does any form of incandescent filament lamp.

d. Incandescent electric lamps, used either by Dowsing or ordinary carbon or metal filament lamps put in suitable reflectors or baths. Recently I have used a much more efficient form, this large, very high candle-power lamp set in this big reflector. This method was introduced in America under the name of leucodescent lamps, but they are just high candle-power carbon filament lamps; this lamp takes 212 ampères at 200 volts.

e. Heat is obtainable in a similar way from a mantle, either ordinary or specially made, heated by gas in an inverted burner. This one I have here is the direct outcome of the visit of our division to South Metropolitan Gas Works, and I have to thank them for the great care they have taken in making this (and reflector for electric lamp, too) according to my requirements.

These various forms of heat baths are useful in sprains, myalgias, neuralgias, neuritis, as in sciatica, lumbago, in arthritis, and contractures due to rheumatism or other like forms of intoxications, and also, of course, used to produce, when desired, sweating in renal diseases. I find the arc light and the large incandescent are by far the most pain-relieving of these methods and the least enervating or tiring, and I often use the arc and incandescent lamps combined. The heat from this gas burner is especially applicable in patients' own houses.

3. Light.-The uses of light, as apart from heat, are many and of decided utility.

From carbon arc lamps, as in the well-known Finsen arc lamp. A great disadvantage of this form of light treatment is that the part to be treated must be rendered anæmic, usually by pressure, or, as done more recently on mucous membranes, by adrenalin, and the area, therefore, is very small-about one square centimetre only. On this