66 The Castner-Kellner Alkali Company, Ld. v. The Commercial "decomposing chamber the amalgamation of the metal that is being separated by the electrolytic decomposition of the electrolyte. In this way, a con"siderable output can be obtained from the apparatus with a comparatively "small quantity of mercury, because both operations can take place "simultaneously and uninterruptedly. 66 5 "In the drawings filed with my Provisional Specification, Fig. 1 is a vertical "section taken through one cell of an apparatus constructed according to this "invention; Fig. 2 is a longitudinal section, to a smaller scale, taken through "the whole apparatus; Fig. 3 is a horizontal section on the line y—y of Fig. 2 ; "and Figs. 4 and 5 are sections through the bell showing two different forms 10 "of construction of the latter. In the accompanying drawings, Fig. 6 is a longitudinal vertical section illustrating a modified construction of the apparatus shown in Fig. 2. Fig. 7 is a vertical section, and Fig. 8 a horizontal section, taken in different planes, showing a further modified construction of "the said apparatus. Fig. 9 is a vertical section through a cell of the apparatus, 15 "similar to that shown in Fig. 1, but provided with a short circuited secondary "electrode for the purpose of rapidly removing the alkaline metal from the "amalgam that has been formed. 66 66 66 66 "The apparatus shown in Figs. 1, 2 and 3 comprises a vessel A for the "reception of the electrolyte to be decomposed, and a trough B inserted or 20 66 suspended in the vessel A, this trough having in its bottom openings which are surrounded by projecting borders b' that serve to prevent the escape, "through the said openings, of the layer of mercury C which serves as a cathode "and covers the bottom of the trough. The anodes D are arranged in the "electrolytic space of the vessel A, horizontally or vertically, and in the latter 25 "case may, as shown, also project through the openings b into the trough B. "Each of the trough openings is covered over by a bell E of non-conducting "material, such for example, as glass, stoneware, porcelain, or ebonite, which dips at its lower free edge into the mercury and is of greater width than the opening b, so that it can be moved to and fro through a certain distance over 30 "this opening, the extent of this movement being limited by the upwardly "projecting border b'. The bell thus encloses the decomposing chamber com"municating with the vessel A, and forms an electrically non-conducting "partition between the decomposing chamber and the combining chamber of "the trough B which is charged above the mercury cathode C, which constitutes 35 "the seal, with water, acid or other substance with which it is desired to cause "the cation, previously taken up by the mercury cathode, to combine. In order "that the mercury shall not become displaced by the lower end of the bell E sliding over the bottom of the trough B when the bell is being moved, slots 6. or notches e or b2 are provided respectively in the lower edge of the bell, (as 40 "in Figs. 1 and 4), or in the bottom of the trough, as in Fig. 5. A gas exit "pipe F leads from the decomposing chamber to the exterior of the vessel A. "The anode D and the mercury cathode C are connected to the terminals of a "suitable source of electricity. 66 "In an apparatus of large size, such as is intended to be employed on an 45 "industrial scale, the whole of the bells E are preferably united to form a cover "which is provided with partitions and is adapted to be moved to and fro in "the trough B, the spaces E' between every two bells being arranged to "communicate by means of lateral openings with the trough B, as shown in "Fig. 2. The gas exit pipes F are then arranged in such a manner that the 50 generated gas is led through all the bells in succession and is drawn off from "the last bell. 66 "The manner of working the apparatus is as follows:-The electrolyte, for "instance a solution of common salt, within the vessel A and the decomposing 66 66 66 66 66 66 The Castner-Kellner Alkali Company, Ld. v. The Commercial spaces or chambers, becomes decomposed by the electrolytic action which "takes place under the bells E, the liberated chlorine gas being led off through "the pipe F, whilst the metallic sodium forms an amalgam with the mercury "cathode C which is situated within the bells E on one side of the anodes D, 5" viz. on the right hand side in Fig. 1. If now the bells be shifted to the left, "into the position shown in dotted lines in Fig. 1, the stationary mercury "cathode together with amalgam becomes thereby situated in the combining "chamber of the trough B which is charged, it may be for instance with water. "The sodium separates out from the amalgam and combines with the water to 10"form sodic hydrate. At the same time, by the shifting of the bells, that portion of the mercury which was previously situated outside the left hand "side portions of the bells, that is to say, in the combining chamber, will now "be located in the decomposing chamber, and acts as the cathode to again "produce an amalgam with the sodium which is continually being separated 15 “in the said decomposing chamber. If the bells, after a suitable interval of time, be shifted back into the position shown in full lines i.e. to the right "hand, the mercury on the left hand side of the anodes, together with the "amalgam formed thereon, again becomes situated, in the combining chamber "of the trough, and consequently within the sphere of action of the water in 20"such chamber, whilst on the other hand the mercury situated on the right “hand side of the anodes, and the amalgam portion of which has been acted upon in the meantime by water to remove the sodium therefrom, becomes again situated in the decomposing chambers for the purpose of forming fresh amalgam. It will thus be seen that by the to and fro movement of the bells, 25"the transposition of the amalgam formed in the decomposing chambers to the combining chamber, and the practically continuous formation of caustic soda "in the latter, are caused to take place alternately on the one side and on the "other side of the anodes, whilst the mercury cathode itself remains at rest." [The Provisional Specification was verbatim the same as the Complete 30 Specification down to this point, except that in lieu of "in the drawings filed. "with my Provisional Specification," it read "in the accompanying_drawings," and it did not contain any reference to or description of Figures 6, 7, 8, and 9.] "It is obvious that the arrangement of apparatus herein before described can "be modified by causing the generation of chlorine to take place outside, and 35"the decomposition of the amalgam to take place inside the bells E. In this "case, the decomposing and forming chambers are merely interchanged. Fig. 6 illustrates a construction of apparatus of this kind, in which the "vessel A contains the mercury cathode C and the solution of common salt "to be decomposed, whilst the bells E that dip into the mercury, are charged 40" with water with which the sodium that becomes separated from the amalgam on the shifting of the bells, combines to form sodic hydrate. The vessel A is "provided with a cover A' that is adapted to close gas-tight, and from which "leads a pipe F that serves to carry off the chlorine gas generated in the said "vessel. The cover is provided at a suitable place with an opening which is 45" closed by means of a movable cover A' that preferably dips into a sealing liquid for the purpose of making a gas-tight joint at this part. Through the cover A there passes a pipe H which serves for discharging the hydrogen that "forms in the bells E and is supplied to the pipe H by connecting pipes H1. "The bells are rigidly connected together, and, as in the previous case, are so arranged that they can be moved to-and-fro in the vessel A, this movement "being shared by the pipe H and the sliding cover A. The positive terminal "wire leading to the source of electricity, is electrically connected by a "conductor that is inserted in a tight manner in a glass tube I capable of move"ment in a stuffing-box in the wall of the vessel to the upper part of each of 312 66 66 66 66 50" 66 The Castner-Kellner Alkali Company, Ld. v. The Commercial "the bells E, such upper part being made of electrically conducting material "whilst the lower part of each bell, which dips in the mercury, is either made "of, or covered with a non-conducting material, the upper part of the bell thus "constitutes the anode. The negative terminal wire is connected to the mercury. "Instead of being slidden along rectilinearly, the bell E, or the vessel A, or the 5 "bottom of the latter, may have a rotary motion imparted to it. An arrangement "of apparatus of this kind is shown in Figs. 7 and 8. Here the vessel A, "which contains the mercury cathode C, is constructed in the form of a disc "provided with an upwardly projecting edge and the hub of which is fixed on a "vertical shaft K that is rotated by suitable means. The decomposing and 10 "combining chambers are formed by means of fixed radially arranged bells E "which are connected together so as to form a cover provided with partitions, "as in the arrangement shown in Fig. 1. The decomposing and combining "chambers follow each other in succession and are respectively provided with "the chlorine discharge pipe F, and with pipes H for discharging the hydrogen. 15 "A number of such disc-shaped vessels A with radially arranged bells E may "be mounted one above the other upon one and the same shaft. Also the disc "shaped vessels A may be fixed, and the bells E be mounted on the shaft K so as to rotate therewith, which is equivalent to the mere reversal of the apparatus described with reference to Figs. 7 and 8, and requires no further 20 description. The manner of operation is the same as before described, in all cases. If it be desired that the alkaline metal shall be rapidly removed from "the amalgam formed, then in the case of apparatus of the kind herein "described, there may be employed the method specified in Claim 7 of the "Specification of my British Patent No. 17169 of A.D. 1892, whereby the heat 25 "liberated in the formation of amalgam is converted into electrical energy. "For this purpose, into the trough B of the apparatus (Fig. 9) or into the "bells E (Fig. 6), or into the combining cells of the bells E (Fig. 7), that "is to say, always in the chamber in which the separation of the sodium is to "take place, there is suspended a third electrode G which is electrically 30 "connected in any suitable way, to one of the terminal wires, viz. that "extending from the mercury cathode (Figs.. 6 and 9), thereby forming a "short-circuited secondary element composed of the mercury cathode C and the "electrode G, which element effects the rapid separation or removal of the "alkaline metal from the amalgam. Each third electrode G may be carried 35 "either by the corresponding bell E, or by the bottom of the vessel A, through "any suitable connection which should be of non-conducting material, or be "covered with such material. 66 66 66 "Having now particularly described and ascertained the nature of the said "invention and in what manner the same is to be performed I declare that what 40 "I claim is :-(1) An apparatus for the electrolysis of metallic salts with the "aid of a stationary mercury cathode, in which partitions or bells capable of "being moved to and fro, and dipping into the said mercury cathode, are "arranged to separate the decomposing and combining spaces or chambers, from "each other and by their to and fro movement, to cause the mercury cathode to 45 "be located alternately within the sphere of action of the electrolyte and of the "substance to be combined with the cation produced, substantially as herein"before described with reference to and illustrated by Figs. 1 and 2 of the drawings referred to. (2) The modification of the apparatus specified in "the preceding claim, in which the movable partitions or bells are provided 50 "with pipes H H' for carrying off hydrogen, and are arranged in a closed vessel "A which contains the mercury cathode and is provided with a pipe F for carrying off chlorine, substantially as herein before described with reference "to and illustrated by Fig. 6 of the accompanying drawings. (3) The 66 66 5 " 66 The Castner-Kellner Alkali Company, Ld. v. The Commercial " modification of the apparatus specified in Claim 1, in which one or more "vessels A is or are mounted on a vertical shaft so as to be capable of rotating "relatively to the fixed partitions or bells that dip into the mercury cathode "carried by the said vessel or vessels, or in which the said partitions or bells are capable of rotating in a fixed vessel or vessels, substantially as herein before "described with reference to and illustrated by Figs. 7 and 8 of the accompanying drawings. (4) In apparatus of the kind specified in the "preceding claims, the arrangement of a third electrode G in the combining"chamber or in each such chamber, the said electrode G, or each of them when 10"there are more than one, forming with the mercury cathode a short circuited "secondary element, for the purpose of rapidly removing the alkaline metal "from the amalgam substantially as herein before described with reference to "and illustrated by Fig. 9 of the accompanying drawings. (5) In apparatus "of the kind specified in the preceding claims, the arrangement of slots or 15 "notches e or be in the edges of the partitions or bells, or in the bottom of the "vessel that contains the mercury cathode, for the purpose of obviating "displacement of the mercury when moving the partitions or bells relatively to "the vessel, substantially as herein before described with reference to and "illustrated by Figs. 4 and 5 of the drawings herein referred to." 20 The Defendants' apparatus complained of in this action was made according to the Specification of Patent No. 21,509 of 1896, granted to John Gustav Adolph Rhodin, for "An improved electrolyser or electrolytic "apparatus." 66 The Complete Specification of the patent is as follows:-"My invention. 25" relates to an improved electrolyser or apparatus for use in electrolysis and my object is to construct a cheap simple and efficient form of apparatus. "In constructing my improved apparatus I employ a cylindrical or other "suitably shaped vessel of earthenware or other suitable material with a flat "base and open top. On the inside of the bottom I form radial or other ribs or projections. Inside and concentric with this vessel I fit a second vessel of "earthen ware or other suitable material in the bottom of which are formed a "series of tubes or hollow projections in which are fitted a corresponding series "of carbon rods all in metallic contact with the positive pole of a dynamo or "other source of electricity. The tubes on the bottom of the second vessel 35" project into a layer of mercury covering the bottom of the first vessel and in 30 The Castner-Kellner Alkali Company, Ld. v. The Commercial "metallic contact with the negative pole of a dynamo or other source of "electricity. A quantity of water or other suitable liquid is placed on the 66 mercury in the first vessel and in the interior of the second vessel is placed a suitable electrolyte such as a solution of Chloride of Sodium or Nitrate of "Sodium or dilute Sulphuric Acid etc. The second vessel is closed by a cover 5 "which is fastened to it and may be provided with an outlet pipe or passage "through which gases liberated during the electrolysis might escape. "The second vessel is fitted and provided with means whereby it may be "rotated. 66 "In the accompanying Sheet of Drawings-Figure 1 is a transverse vertical 10 "section of the improved apparatus. Fig. 2 is a plan of the under side of the "inner vessel, and Fig. 3 a plan of the bottom of the outer vessel. In the "Drawings, a designates the outer cylindrical or other suitably shaped vessel "which I prefer to make of iron and b is the inner concentric vessel which I "prefer to make of earthenware. The bottom of the vessel a, as shown in plan 15 "in Fig. 3, is provided with radial or other ribs or projections c (Figs. 1 and 3) "and the bottom of the vessel b as shown in Fig. 2, opens out into a series of "hollow projections or tubes ƒ of any suitable section. The top of the vessel b "is closed by a suitably shaped lid or cover which may be made in one piece "with the vessel, as shown in Fig. 1, or may be a separate part secured thereto. 20 "Through holes in this lid I fit a series of carbon rods or other suitably shaped "carbons or anodes of other material g which fit closely into these holes and "project into the above mentioned hollow projections f yet without coming in "contact with a layer of mercury d which seals the openings of the hollow projections when the apparatus is put together. These carbons or anodes are 25 "put in metallic contact with one another by suitable means such as for "instance by casting a layer of lead h into an annular space formed by the lid "and into which the ends of the carbons or anodes project. The combined "anodes might conveniently be brought into metallic contact with a ring of "metal which surrounds a tube q into which the lid of the vessel may be 30 "suitably prolonged. The metal ring 7 may then by means of a metallic brush "m be put in contact with the positive pole of a dynamo or other source of "an electric current. The above mentioned hollow projections or tubes ƒ project in a layer of mercury d which seals the inner part of the vessel b "from connection with that part of the outer vessel a which is not occupied by 35 "the inner vessel b. On the top of the mercury and filling this last mentioned part of the vessel a is a layer of water or other suitable liquid p. The inside "of the second vessel is filled with a solution of an electrolyte generally one "with a metallic kation forming the layer n. The second vessel is further "provided with means for slowly rotating it, such as for instance, a pulley t 40 "fixed round the tube q and provided with a collar running in a bearing s supported by an arm w or the like, which also prevents the second vessel b "from touching the bottom of the first vessel a. The tube q may be connected "with a system of gas conducting tubes by means of a liquid seal or joint k. "When the first vessel a is made of iron, which is the preferred material, the 45 "layer of mercury is made into a kathode simply by connecting the vessel a "with the negative pole of the above mentioned source of electric current. 66 66 66 66 b "In operation, when the electric current is flowing, the second vessel b is "slowly rotated during which operation the projections ƒ agitate the layer of mercury d which however, is prevented from revolving by the ribs or 50 "projections c. The amalgam formed at the bottom of the projections ƒ is then "mixed up with the main bulk of the mercury principally by these projections "sliding over the mercurial surface and by the diffusing action between the mercury and the amalgam and by the internal movement set up by the 66 |