thin pancake batter results. Much stirring should be avoided, as this causes 

 bubbles which remain as unwelcome holes in the cast. This mixture is then 

 poured over the wax and allowed to stand for an hour or more. Then the 

 block can be lifted, the sand washed off, and block and Embedded wax dropped 

 into a pan of boiling water. The water should be kept hot until the wax has 

 all melted and risen to the surface. When cool, the film of wax may be broken 

 from the top of the container and the cast taken out and dried. It should be a 

 perfect reproduction of the original track. A coat of paint may be applied to 

 the cast, after it is dry, and, if desired, another color applied in the hollows 

 of the print. 



The drawback to the wax mold is that only one cast is possible. If more 

 are desired, the original field work must be done in plaster. Sticks or mud 

 will serve as retaining walls, and the plaster must be given plenty of time to 

 set (it will become warm and then cool again in the process) before it is lifted. 

 After washing, it must be waterproofed with several coats of oil or hot vaseline, 

 or by boiling it in melted paraffin. Then any undercuts or places which, from 

 their shape, would not separate easily from the cast to be made should be filled 

 out with modeling clay or plasticine. The casting is handled just as with the 

 wax mold, but the block must be allowed to dry thoroughly before any attempt 

 is made to separate the two pieces. Then they should be tapped lightly, and, if 

 the undercuts were properly filled and the mold well oiled, they should separate, 

 leaving a perfect cast and the original mold ready for re-oiling and use in mak- 

 ing another copy. To separate large blocks one can sometimes start small nails 

 all along the line of junction between the two and tap them gently in sequence 

 with a hammer. 



Plaser-of-paris can he bought in any paint or hardware store for about 

 five cents a pound. It must be kept dry until used. If it begins to warm or to 

 set before one is ready to pour, it is useless and should be thrown away. Adding 

 more water will not help it. Plaster molds must be waterproofed and oiled 

 before each cast is made, or mold and cast v^^ill enter into such a union that one 

 or the other must be sacrificed and broken away piece by piece. 



Tracks in the snow are difficult to cast, impossible if the snow is soft and 

 the temperature above freezing. If colder, one can use ice water to mix the 

 plaster, or add snow to the water used, and flow on a rather thin mixture from 

 the side. A thin plaster mixture, flowed on from one side, usually works well on 

 tracks in dust or fine sand. 



A good collection of animal tracks is a worthy achievement and makes 

 an interesting display. Collecting tracks can be recommended as an entertain- 

 ing and instructive hobby, not injuring the wild animals and not requiring a 

 license or the expensive equipment or ideal conditions necessary for 

 photography. 



557 



