TlIK MlCliOSCOPE. oS'-i 



liquid mud to a suitable vessel of tin or china, of at least six or more 

 inches in diameter, and not over five or six inches deep, put therein 

 as much liquid mud as will fill one inch in depth, and fill up the 

 vessel with clean water, and stir rapidly the contents to liberate the 

 flocculent matter from the heavier contents; after allowing the con- 

 tents to settle for ten minutes, by the watch, with a section of drop- 

 light rubber tubing at least eighteen inches in length, siphon off the 

 water to within half or three-quarter inches of the bottom of ves- 

 sel, renew the water and then stir up quickly, and after five 

 minutes siphon off the water, with the aid of the rubber tube, to 

 within half an inch of the bottom. At this point a material por- 

 tion of the mud has been removed, which it is not essential to treat 

 further. The sediment left, after siphoning off the water the second 

 time, is transferred to any shallow tin or other vessel for convenience. 



The next step is to place in a shallow concave glass, which may 

 be secured at any photographer's, it being used by th^m for crystal php- 

 tographs, the size about four by six inches, — a shallow layer 

 of the diatom-bearing mud, and adding water as a top layer, 

 gently gig the glass back and forth making the wayes run from end 

 to end, and side to side, and tilting the off or front end. This manip- 

 ulation forces the large and small sand-grains to densely cake and 

 pack together, and, at the same time, forces to the surface a large 

 percentage of the diatoms, and most of the vegetable debris. 

 After a few moments of gigging, the surface fluid is gently poured 

 off and caught in a separate settling vessel, and the heavier sand 

 dropped into a waste receptacle. It might here be observed that a 

 very small percentage of matter would be the outcome of the first 

 manipulation, as detailed, and that the bulk of the material was 

 removed from the crystal glass as rejected sand; it can generally be 

 relied upon, that what is left on the gigging glass would not do to 

 manipulate again, and the diatoms must be looked for in the light, 

 coherent, flocculent and vegetable debris matter that floated over in 

 the first removal of the surface fluid. Repeat substantially the same 

 manipulation until the whole of the mud has been gone through 

 with, and when, finally, what is left of the half-pound of mud as 

 started with is collected together, it will appear very little, indeed, 

 but the coveted gems are therein, or do not exist in the mud. The 

 next step is to transfer what has been saved in the various partial 

 concentrations, and transfer all of it to the crystal glass, and add 

 clean water and gig it again several times in succession to remove 

 additional sand, and to get a further concentration of the desirable 



