attempts to obtain a spark, while a patient calmly waited with expectancy for the successful termination of his feat. Some of you may have had such an experience. I suggest, therefore, that you follow the directions given, with some regard to their details:

(1) See that the plates and charger are dry. If not, you can easily render them so by exposing the machine to strong sunlight, and by putting an abundance of chloride of calcium in trays at the bottom of the case. This may require some hours of delay. Always open the door of the case if the sun's heat be used; and close them tightly (by means of the milledscrews which perforate the door) as soon as the machine regains its charge.*

(2) After you have got the plates thoroughly dry, start them in rapid revolution, by turning the driving-wheel from left to right as you stand facing it. Now apply the chargers lightly near to the edge of the revolving wheels for a second or two, and then sweep them across their face at intervals of a few seconds, until the machine starts. The poles should be approximated to within one half-inch, and the chains should not be connected with the poles.

(3) If the machine fails to start, in spite of these directions, you can then take a piece of cat-skin and warm it thoroughly over a gas-jet. Then set the wheels in rapid revolution and apply the warmed catskin as a rubber (to the plate with the buttons on it) as close above the metal comb as it is possible to hold it. This seldom if ever fails; but it requires the opening of the door of the case.

(4) Be sure that the poles are well dried with chamois-skin before the machine is put in action; also, that the poles are closely approximated but not in contact.

* If you cannot spare the time for these procedures, a large alcohol lamp may be lighted within the case. The air may thus be heated sufficiently to temporarily render the machine useful. I am aware that I have been criticised (in a carping spirit) for offering this suggestion in print; but, as a temporary expedient, it oftentimes proves a valuable aid in rapidly regaining a lost charge, and rendering an induction-machine efficient.

I have frequently known the nozzle of a hot-air furnace (such as is used in giving a hot-air bath to a patient beneath the bed-clothes) to be directed into the case of an induction-machine for the purpose of drying the plates when very damp. At one time I tried to build a machine with a tube passing through the case, by means of which the air in the case might be heated indirectly without opening the door; but I found it impracticable, for many reasons.

METHODS OF APPLICATION OF STATIC ELECTRICITY.

Static electricity can be applied in several ways to a patient. Each of these methods has some therapeutic effects which are peculiarly its own. Moreover, the sensations experienced by the patient during the application are greatly modified by the method employed. For these reasons, it is necessary to go into greater detail respecting the management of a static machine than that of any other electrical apparatus in medicine with which I am familiar.

We can apply apply the static current to a patient in the following ways:

(1) By the "indirect spark."

(2) By the "direct spark."

(3) By the "Leyden-jar spark" or "static shock." (4) By "static insulation."

(5) By the "static breeze."

(6) By the "static induced current."

THE INDIRECT SPARK.-To administer static electricity by this method, the patient is first placed upon the insulated platform, and sufficiently removed from all surrounding objects to prevent the escape of the charge from the patient to them. The

FIGURE 13.-The indirect spark.

machine is then connected with the patient by a chain, which is either held or simply attached to the stool on which the patient sits. The chain must be sufficiently elevated from the floor to prevent "grounding" of the current. It may be attached to

either the positive or negative pole of the machine, according as the operator may desire positive or negative insulation. A chain is then attached to the other pole of the machine, and is "grounded." This can best be effected by attaching it to the gas fixture or a faucet attached to a constant water supply. If this is not convenient, the chain may be thrown upon the floor, when not carpeted, in case the generating power of the machine is ample.

The poles of the machine are now widely separated and the wheels put in rapid motion. You will notice that the hair of the patient immediately rises; and, in a dim light or total darkness, you should perceive a peculiar purplish light escaping from the tips of the finger-nails, the hair, and other parts of the body which are more or less pointed. The rapidity of this escape is influenced, (1) by the extent of the charge; (2) by the proximity of a part to some surrounding object; and (3) by the condition of the atmosphere, as regards its moisture. As the patient moves his finger-tips near the door-casing or some article of furniture not insulated, some of you may be able to perceive this escape of electricity, even in this strong light.

Now we have a condition which is known as "static insulation." If the machine is a powerful one, it may be carried to a high point. The patient happens to be charged, in this particular instance, with positive electricity, because he is connected with the positive pole of the machine.

*

The final step consists in presenting to the part which you wish to influence a brass ball on the end of an insulated handle. This electrode is connected, as you see, with a gas pipe by means of a brass chain. A water pipe makes an equally good connection. When this ball reaches a certain degree of proximity to the patient, you notice that a discharge of the accumulated electricity occurs in the form of a "spark." This is known as the "indirect" spark; because the electricity takes an indirect course (through the earth) to form a circuit. It leaps from the patient and escapes to the earth down the gas-pipe or whatever grounding the electrode may chance to have.

The length of the "indirect" spark is directly proportionate to the generating power of the machine-supposing, of course, that all other factors in the application are equal (such as the

*The length of the spark elicited depends on the power of the machine, the dryness of the atmosphere, and the perfection of the insulation of the patient. I frequently have drawn a spark of eight inches by this method.

humidity of the atmosphere, the completeness of insulation, etc.).

The volume of the spark is modified by the size of the brass ball on the end of the electrode. A large ball will produce a

heavier spark than a small one.

The therapeutical effects of this method of application will be discussed later. I would call your attention, however, to the violent muscular contractions which occur with each spark.

This method is somewhat painful. The withdrawal of a spark leaves a "weal" or lump, which somewhat resembles a recent mosquito-bite. They almost entirely disappear when friction is employed after the application; hence, it is my custom to rub the part with my handkerchief, if exposed, (the face or hands, for example,) after the application.

I would caution you here, in passing, against giving static sparks (by any of the three specified methods) to a patient on his first visit. You are apt to frighten a patient, unless he is well prepared for it. Again, patients grow tolerant of this method of treatment after a while; hence, you can gradually increase the volume and length of spark at successive sittings without endangering the patient's confidence in you or creating alarm. You can regulate the length of the spark by the speed of revolution of the plates of the machine.

For some hours after such an application the patient feels a sense of heat at the spot where the spark occurred. This is not at all unpleasant to many. Some patients even speak of it as agreeable.

By using a wooden ball in place of a brass one, a number of very fine sparks are simultaneously elicited-giving to the patient a feeling aptly compared to a "shower of sand." This electrode is admirably adapted for use about the eye or the face, although this is not the limit of its usefulness.

Finally, it is not essential to this form of application that the clothing be removed; as the finest silk or woolen fabric is not injured by it. This is a great point in favor of static application, especially in the treatment of females.

Perhaps you have noticed that I use a second electrode with a ring of brass attached to the insulated handle, through which the chain is passed before it is attached to the ball-electrode. This is to keep the chain away from the patient, so that sparks will not be caused at points where you do not desire them to occur. A little practice will enable you to handle both with one hand, while you turn the wheels of the machine with the other.

Sometimes it may be necessary to have the patient stand rather than sit upon the insulated platform while these applications are being made.

Let us pass now to the second method enunciated.

THE DIRECT SPARK.-By this method, the circuit between the poles of the machine includes the patient only. He sits on the insulated platform, which is connected with one pole of the machine; or one pole may be directly attached to some particular extremity of the patient, when the effects of the current are to be concentrated as much as possible upon that member. The electrode is attached to a chain, which is fastened to the other

pole of the machine. The length of spark to be administered is regulated by the extent of separation of the poles of the machine and the speed of revolution of the plates. The further apart the poles, the longer and more severe is the spark.

The ring electrode is employed (as in the former method) to protect the patient from an accidental contact with the chain attached to the electrode.

In neither this nor the method previously described are Leyden-jars employed.

I question, personally, whether the selection of the poles for the attachment of the electrode has much, if any, influence over the therapeutical action of the "direct" spark. If it has, I have not as yet clearly formulated in my own mind any deduction respecting this point.