156 SILVER-LEAD DEPOSITS OF EUREKA, NEVADA. 



Sometimes the flooring is removed before the spaces between the timbers 

 are filled. 



Method of framing in the Richmond. — Fig. 9 represents the posts, caps, and ties as 

 framed in the Richmond mine. The tenon of the post is 9 by 6 by li inches; 

 that of the tie, 9i by 6 by li inches. The tenon proper of the cap is 9 

 by 7* by 3 inches, but there are several shoulders on the cap made to fit 

 the spaces left between the post and tie. The dimensions of all these differ- 

 ent parts can be seen in Fig. 9, and the manner in which they come together 

 in Fig. 8. 



This method of framing is complicated, and therefore expensive, but it 

 is claimed that it gives great strength to the joint. Upon an examination 

 of Fig. 9 it will be observed that the tenons of the posts, and also some of the 

 shoulders of the caps, are cut somewhat short of what would be their proper 

 length if they were framed to meet exactly. This is to allow the timbers 

 to come together easily, as any irregularities in the joints caused either by 

 imperfect cutting or subsequent warping would interfere with their proper 

 fitting were not some space allowed. This is the more necessary on account 

 of the complicated system of joining. Pressure soon causes any imperfect 

 parts to meet. 



Method of framing in the Eureka. — Fig. 10 represents the timbers as they are 

 framed at the Eureka mine. The tenon of the post is 8 by 8 by 2 inches, 

 that of the cap 6 by 8 by 4 inches, and that of the tie 12 by 8 by 2 inches. 

 The tenons of all these are also cut somewhat scant, but as there are not 

 so many shoulders as in the Richmond timbers they do not need as much 

 play and are easily fitted together. Timber men usually prefer the Eureka 

 to the Richmond method, contending that the timbers are equally strong 

 and more easily framed. The Eureka timbers seem best calculated to resist 

 pressure from all sides, while those of the Richmond offer the greatest resist- 

 ance parallel with the caps. This would be what was required in timber- 

 ing an ore body the greatest dimension of which was along the course of 

 the lode, as is the case with Comstock bonanzas. In this case the ties would 

 be placed parallel to the walls and the caps at right angles. In Eureka, 

 however, the ore bodies are very irregular and the pressure is usually about 

 the same from all sides. On the first discovery of an ore chamber, too, it 



