Pomona Collegk Journal of Entomology 387 



These schedules are printed on fairly stiff paper so that they may be 

 tacked upon a board for the use of the generator of the outfit. The figures 

 are black and large enough to be plainly seen by the light of a torch or 

 lantern on the darkest night. Half and quarter ounces are omitted, because 

 of the difficult)- in reading the small fractions at night and because few scales 

 are fine enough to register so small amounts accurately. All less than 

 half ounces are placed in the lower figure, while half-ounces or over are 

 placed in the next higher figure. A more convenient way of fixing up this 

 schedule is to have a cylinder made of zinc, with a narrow slot, the width 

 of a row of figures, covered by a glass, and a wooden roller on tlie inside, 

 similar to a rolling pin. Each end of the cylinder is closed with a caj) 

 with a hole in the center, in which turns the handles of the wooden roller. 

 The chart or schedule is attached to the roller so as to revolve in the cylinder. 

 The figures of the distances around are pasted along the top of the slot to 

 conform with the like numbers on the schedule. In finding the dosage one 

 has only to turn the roller until the distance over shows at the left-hand 

 end of the slot, the figure at the top of the slot shows the distance around. 

 In this way, the chart is kept perfectly dry and bright and the possibilities 

 for making a mistake are reduced to a minimum. It is right to state here 

 that this arrangement was first invented by Mr. McFadden, who uses it on 

 all of his chemical charts. 



FIELD PRACTICE 



The Morrill System of marked tents was, of course, used with the above 

 charts. The distance around the tree was taken with a tape line. It was 

 early learned in our experiences that pacing was unreliable, because every 

 man paced differently and some were very careless about the work at best. 

 It takes very little longer to measure, than pace, and as one man had to be 

 kept at this work it made the expense no greater at all and made no delays. 



Five men are used on an outfit of 20 to 30 tents, the duties of which 

 are as follows : 2 tent pullers ; 1 taper, who measured the trees around and 

 passed along the empty generators ; 1 generator who measured the acid and 

 placed the generators under the tents ; I cyanide man, who kept the records, 

 weighed the cyanide and held up the sides of the tents for the generator to 

 place the pots in position. Care must be taken that no man who handles aeid 

 touches a tent. The taper wears a cloth glove, which will absorb anything 

 that might adhere to the handle of the pot. 



A complete record of the dosage of every tree is kept, giving not only 

 the dosage, but the temperature and time at the beginning of each throw. 

 This field chart is tacked to a wooden roller, which fits into a zinc cylinder 

 similar to the one used for the chart, except that the slot is open so that 

 the dosage may be written dowiL This is, I consider, a very important 

 practice, for in cases of burnings or poor work the original dosage, with 

 time, exposure, and temperature are at hand for ready reference. Many 

 otherwise unaccountable damages, have thus been traced to an over dose 

 or a cold period, while an imderdose may explain a poor job. 



