038 



Popular Science Monthly 



A Simple Electrical Device for 

 Purifying Water 



ADEVICIC for purifying water by 

 means of electricity can he made at 

 \ery little cost by the use of a few ele- 

 ments which are easily obtainable. It 

 may be done by procuring an aluminum 



tube A, 4K '"s^- 'o"K. ''"tl iK ins- 

 in diameter. It is immaterial about the 

 gage. Also purchase an aluminum rod 

 B the same length, of %-in. material. 

 A piece of hard rubber, or fiber, C, % 

 in. thick, and i^ ins. each way. This 

 is to be turned in a lathe 

 so it will fit into one end 

 of the aluminum tube. 



Tile rul)ber lork thus 

 provided has a central 

 hole to receive the ^-s 

 aluminum rod, as shown. 

 One of the set-screws D, 

 for holding the head C 

 and tube A together, 

 serves as a means for 

 connecting with one of 

 the terminals /'", while 

 a screw /'' in the upper 

 end of the rotl B acts as 

 a binding-post for the 

 other terminal G. 



The tube B should 

 have a few notches, as 

 at //, at its lower end. 

 An inch from the upper 

 end are two or more 

 holes /, the object be- 

 ing to provide a means 

 for circulating tlic water 

 wluii the current is do- 

 ing tlic work. 



Tins manner of treat- 

 ing water is known as 

 the direct electrical 

 method; whereas ozoni- 

 /ation is the indirect means. F^oth sys- 

 tums, however, depend on the generation 

 and application of oxone, or na.scent o.\y- 

 gen, which attacks the organic matter in 

 water. The result is that such substances 

 are coagulated and precipitated, thus 

 leaving the water pure and wiiolesome. 

 This system is in every respect superior 

 In filtration, 'i'he latter method cl.irifies, 

 i)Ut does not purify. 



Tiie arliiie thus ronslru(tc(l is .ul- 

 Miirably adaplcil li> st.md in a glass of 

 water, ;ls shown, fiir a minuli- or two. 



The water moves up along the 

 space between the two electrodes 

 and down outside the tube 



and then be taken out. Theaction of the 

 current in passing through the water 

 between the electrodes A, B, causes a 

 milky appearance, which gradually 

 changes. The solid matter first gathers 

 at the surface of the water, and after 

 giving off tlie gases contained in the 

 globules, falls to the bottom, leaving 

 a clear liquid. 



A wonderful test of the efficiency of 

 tliis method of purif\ing may be made 

 b>' adding a few drops of ink to the water 

 before putting in the device. It will be 

 found that the precipi- 

 tate will contain all the 

 ink, and that the water 

 will be as clear as before. 

 The water moves up 

 along the space between 

 the two electrodes, pass- 

 es out through the holes 

 / and down outside of 

 the tube B. By means 

 of the circulation thus 

 set up every part of the 

 water is treated and tiie 

 oxygen bubbles pass 

 through tlie water, thus 

 attacking the organic 

 matter and eliminating 

 it entirely. 



The dui^lex wires E, 

 G, should have an elec- 

 tric jilug at the other 

 end which may beapplieti 

 to the ordinary socket. 

 The dimensions given 

 will be correct for a 220- 

 \()ll circuit. In ca.se of 

 a iio-volt circuit the 

 tube A should be ij^ 

 ins. in diameter, or the 

 rod B should be larger, 

 say, K '"• or y's '"• '" 

 tii.uneterto give the most eflicient service. 

 There is some dilTerence in the re- 

 sist. mce of various waters, which is not 

 sufficient to require a change in the 

 s|)ecilications, but in such cases the ex- 

 perimenter will .soon learn the correct 

 time required to treat a certain quantity 

 of water, and not allow the (ic%ice to 

 remain in a<'tion too long. 



Till' device will act e(|ually well bv 

 phmging it into a pitcher of water, if 

 left there long enough to thoroughly 

 ozoni/.e the whole. 



