| Show THE MACQUISTON CONCENTRATOR The Engineering and Mining fining Journal has an il illustrated illustrated illustrated il- il article on Mr 1 l process for concentrating gulp sulphide hide ores It is a n very wonderful invention for it reverses all the theories which men have havo heretofore e entertained re regarding garding b concentration r The rhe idea has lias always been heen that the heavy minerals would sink to do the bottom and the gangue b would 1 float awa away This his process is exactly the reverse of that at The rhe mineral floats away r and the gangue falls is bas based d the different to the bottom The rhe idea on affinities a as exhibited b by the ilke various constituents of sulphide ores to the surface tension of the water It ha has been proved that sulphide minerals are arc positively pos pox affected by br the surface tension of the water That is they do not penetrate the surface and sink through the water but are retained on the surface while rock and constituents are affected by it nega tive i That is they break through the surface and sink through the water and it is explained that that all all bodies of or water or any other liquid d has greater cohesion co- co hesion in in its itc free surface that is the surface exposed I to air than ham an anywhere where in its interior because whereas the particles of the interior are mutually attracted by adjacent particles in all d directions those which are ale at the surface have no attractions from the outside outside out out- outside side to counteract the pull from those in the interior The rhe effect o of this is 5 to have bave the mobility of the particles particles par par- on oil the surface while those in the interior are quite mobile The rhe surface as it were is stretched on an cl elastic i s skin kin the file effect being beang b the same as if the surface layer exerted a pressure on the interior The i The production of this surface tension represents represents molecular energy which may mar be measured It Itis Itis Itis is indicated by so-called so efficient co-efficient surface tension It is illustrated bj by blowing a soap bubble on the end of a tube and closing the other end of the tube rube The hubble bubble rem remains J ns the elastic force of the air counter balancing the bubbles on tho the surface But when the tube is opened the surface tension of th the bubble hubble causes it to contract and disappear Ye We have an i idea ea although we know nothing f about it posit positively ely that it is the pressure of the air airon airon airon on the surface of the water which gives the tho top of oi the water so to speak greater density than th that t below and lInd through that density this miracle is worked I At all alb events it is a most marvelous arrangement It upsets all mens men's ideas of oi ore concentrating It is being proved now on a very extensive scale at the Glasgow and Western company's works at Golconda Ne Nev And the ilic concentrates are certainly tile the cleanest cleanest cleanest clean clean- est that were ever turned out ont of or a n mill It would take a a- a great deal of pace space to fully describe the apparatus apparatus apparatus ap ap- ap- ap but the principle t stated in the above and the practical workings of it on a largo scale ecale are as nearly perfect as was ever seen Another feature of it is that the process is practically without cost after iter the theore ore is crushed Of Ot course it needs fine crushing for all the particles dealt with must be necessarily small It isa is a great triumph and it seems to us that it is bound to revolutionize the tho concentration of sul- sul ores |
