APPENDIX I. 



REPORT ON THE ELECTRICAL EXPERIMENTS IN THE BRANDING OF THE FUR-SEAL 



PUPS-SEASON OF 1897. 



By Elmbr E. Farmer, Astiatant to the Commission. 



The earliest experiments in electrical branding, made in the laboratory at 

 Stanford University, were carried on under serious difficulties, resulting from a lack 

 of suitable apparatus and machinery as well as of suitable fur on which to operate. 

 . Having neither low-voltage dynamo nor suitable rheostat, it was necessary to use the 

 incandescent-light circuit, on account of the high voltage of which approximately 

 11,000 watts were used instead of the necessary 300. This excessive voltage caused 

 trouble in the loaded dynamo and reacted on the experiments by changing factors 

 which were supposed to remain constant. 



The only available fur of a living animal approaching that of the seal which we 

 could obtain for use in the early experiments was cat's fur. On this our results were 

 very satisfactory. Searing the outer surface of the sliin of the cat, without burning 

 underneath, was found suf&cient to destroy the hair cells. This could be accomplished 

 with one stroke in about ten seconds, a mark 1 inch wide and about 5 inches long 

 being made. When we came to deal with the actual fur of the seal we found it so 

 different that these early experiments gave us no real idea of what was wanted. 



As a result of the preliminary tests, under your authorization I set about tlie 

 preparation of more suitable apparatus. 



THE APPARATUS. 



The apparatus provided for the work in electrical branding consisted of a direct- 

 current dynamo, compound wound, and weighing 85 pounds. The dynamo was Con- 

 nected to a half-horse power gasoline engine weighing 160 pounds. The gas was 

 ignited by a battery and coil. 



Platinum was chosen as a cautery wire, on account of the high temperature of its 

 melting point and its comparative honoxidizability. The size of wire used was No. 

 18 B. & S., which seemed large enough to insure the required strength at white heat 

 and yet small enough to require only an economical amount of power, with a mini- 

 mum expenditure for replacement in case of fusing. 



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