An arrangement, which constitutes probably the utmost  extent of elaboration consistent with efficiency and economy  in regular work, might consist of a large-sized glass cell,  having immersed in the fluid a cylinder of porcelain, from  the bottom end of which a platinum wire projects to an extent  variable by a screw at its upper end, and having, further,  a kathode in the form of a sheet of lead of suitable size.  The triple type illustrated in Fig. 85 is now generally used,  as it permits a much wider range of adjustment and regulation  (in combination with the primary winding of the induction  coil) than the single type just described.  As further illustrating the simplicity in essentials of this  form of break, we represent in Fig. 86, and describe, one  which may be made for himself by anyone who has even but  slight manual dexterity, and that for a few pence, or, at most,  a few shillings.

An ordinary earthenware or glass jar may be used as a  containing-cell—the larger the better. Through the closed  end of a test-tube seal a short length of platinum wire, and  into the tube pour mercury to a height of 1 inch or more.  Through a wooden cover to the cell, or in some other suitable  manner, as in Fig. 36, suspend the test-tube immersed deeply  in the fluid, and to make connection, dip a wire from the A, Glass jar containing dilute sulphuric acid (1 in 10); B, sheet-lead with  terminal; C, test-tube with platinum point and containing mercury.  positive pole of the source of supply into the mercury. Then  hang over the edge of the cell a piece of sheet-lead reaching to  near the bottom of the fluid, and having a screw at its upper  end to bind a connecting-wire from the negative pole of the  source, and your electrolytic break is complete.

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