366 APPENDIX B 



taken for the purpose of reading the verniers of a theodolite or sextant 

 in star observations. It was used every night and for many purposes. 

 As a matter of necessity, where insects are numerous one turns to the 

 protection of his hammock, and net immediately after the evening meal. 

 It was at such times that I found the electric lamp so helpful. Reclin- 

 ing in the hammock, I held the stock of the light under my left arm and 

 with diary in my lap wrote up my records for the day. I sometimes 

 read by its soft, steady light. One charge of battery, to my surprise, 

 lasted nearly a month. When forced to pick out a camping spot after 

 dark, an experience which comes to every traveller in the tropics in the 

 rainy season, we found its light very helpful. Neither rain nor wind 

 could put it out and the light could be directed wherever needed. The 

 charges should be calculated on the plan of one for every three weeks. 

 The acetylene lamp for camp illumination is an advance over the ker- 

 osene lantern. It has been found that for equal weight the carbide 

 will give more light than kerosene or candle. The carbide should be 

 put in small containers, for each time a box is opened some of the con- 

 tents turns into gas from contact with the moist air. 



Tools. — ^Three or four good axes, several bill-hooks, a good hatchet 

 with hammer head and nail-puller should be in the tool kit. In addi- 

 tion, each man should be provided with a belt knife and a machete with 

 sheath. Collins makes the best machetes. His axes, too, are excellent. 

 The bill-hook, called foice in Brazil, is a most valuable tool for clear- 

 ing away small trees, vines, and undergrowths. It is marvellous how 

 quickly an experienced hand can clear the ground in a forest with one 

 of these instruments. All of these tools should have handles of second- 

 growth American hickory of first quality; and several extra handles 

 should be taken along. The list of tools should be completed with a 

 small outfit of pliers, tweezers, files, etc. — the character, of course, de- 

 pending upon the mechanical ability of the traveller and the scientific 

 instruments he has with him that might need repairs. 



Survey Instruments. — ^The choice of instruments will depend 

 largely upon the character of the work intended. If a compass survey 

 will suffice, there is nothing better than the cavalry sketching board 

 used in the United States Army for reconnoissance. With a careful 

 hand it approaches the high degree of perfection attained by the plane- 

 table method. It is particularly adapted for river survey and, after 

 one gets accustomed to its use, it is very simple. If the prismatic 



