3. Electrolytic breaks, commonly known as Wehnelt’s  breaks, from the name of their originator, are now extensively  used as specially suitable for the heavier currents desirable for  rapid radiographic work. With these breaks a much more  rapid rate of interruption can be obtained, and they are  capable of transmitting currents heavier than any X-ray tube  at present made can stand for more than a few seconds.  They may be used with alternating current (as mentioned  earlier) or with continuous current, but work more efficiently  with the latter.

As the name indicates, these breaks depend upon the  electrolytic action of a current passing between electrodes  immersed in a liquid. If one electrode be of very small area,  the bubbles of gas formed tend to collect on it, and thus  interrupt the continuous passage of the current; then almost  instantaneously these are dissipated, and the current is again  free to pass. A regular succession of accumulation and dissi-  pation of bubbles renders in this manner the current passed  through the cell intermittent in character, and the periodicity  so obtained is much more rapid than with any form of  mechanical interrupter in use. In practice, the electrode of  small area is the anode, and is composed, of platinum, while  the kathode consists of a lead plate of large area.  Dilute sulphuric acid (1 in 10) is commonly used, though  other fluids have been suggested as more suitable for certain  purposes. A cell containing such fluid, and having immersed  in it two electrodes as described, represents the total essentials  of the break, though many elaborations of adjustment have  been introduced.

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