VACATION EXPEDITIONS 223 



them, but I never take chances with valuable plates. 

 When in a tent or the cabin of a small vessel I wait 

 till all lights are out and then work for an hour or 

 two. This sort of thing, when kept up for a month, 

 especially when one arises at dawn, is certainly ardu- 

 ous. After such a tour in Saskatchewan, I slept 

 nearly all the way on the three days' journey home. 

 The experience, none the less, was most invigorating, 

 and I had hundreds of fine plates to the good. 



It is well to learn to change plates in the dark, 

 without a ruby light, by feeling. There come times 

 when it is a great convenience to be able to do this, 

 and it is not as hard as it seems. Before extinguish- 

 ing the light, lay everything out in order. On one 

 side put the empty boxes to receive the plates, previ- 

 ously labelled and dated, so that there will be no 

 possibility of confusion, and on the other the boxes 

 of fresh plates, with the edges cut. The holders are 

 piled directly in front. As you take off the slides, 

 lay them and the holders down each in the same way. 

 After safely packing all the exposed plates, the lamp 

 may be lighted and the ends of the slides inserted in 

 the holders, these being piled up, ready for the in,ser- 

 tion of the new plates when the light is again put 

 out. 



On returning home it is no small task to develop 

 several hundred plates, but this can be expedited con- 

 siderably. Some like " tank-development," that is, 

 mixing a whole wash-tray of very weak developer 

 and inserting a considerable number of plates at once. 



