Trnimtion Studies 28 



Gulton speaks highly of geogniphical Hocieties in the help they provide 

 for <|U!ilifie(l travellers, and then douhtless comes a touch of hiH own 

 pxpeiieiiot!, and 



ilioir moral iriHuuiioe in nut to be cli8roK<ir(le(l, by wiiic-h they KUHtain the courage and p<TiM>- 

 vt-rnnce of li traveller, wlumo special t)i.HtPH find little countenance and Hympathy from the 

 asstK'iateN whom the aucidentH of birth and nei){hlMiurh(KKl have miuie nearest to htu)'." 



He kept frecjuently in his mind the discovery of any means of easing the 

 path of the travelling geographer. Thus we nave his "Table for Itough 

 Triangulation without the usual Instruments and without Calculation " of 

 March 18(30. This wjts a simplified form of measuring the distance of an 

 object (bieadth of river, etc.) lying off the traveller's path first suggested 

 witii more rigorous calculations by Sir George Everest, formerly Surveyor- 

 General of India'. Galton appears to have issued his tjible on a single 

 leaf probably for the use of travellers, and it was afterwards incorponited 

 in the Uinta for Travellers he edited for the Royal Geographical Society. 

 The idea is an e.vceedingly simple one. We proceed thus : 



C,' aC' 



/\ A . 



A b OB 



C is the inaccessible object assumed to be either in the same horizontal 

 plane as our base line AB, or else to be the projection of an object on that 

 plane. We walk ten paces Ac from a peg at A towards C and uisert a j>eg 

 at c. We then walk ten paces towards an accessible object at li and set a 

 peg at h. We pace ch to the nearest quarter pace. Then we walk 100 paces 

 from A to B and in order to maintain a straight line always look at a 

 distant object E beliiud B ; at a which is 90 paces fronj A we insert a peg 

 and then do ten more paces to B (peg). Next we step ten paces Be' from d 

 towards C, and finally pace c'a to the nearest quarter pace. The numlier of 

 paces in eh and c'a are the two arguments by which we enter horizontally 

 and vertically Galton's Table, and under them we find AC given in paces. 

 If we enter with c'a and ch horizontally and vertically we find BC. If AB 



' Loc. cil. p. 100. 



^ Jimrnal of the Hoyal Geogra/ihicn/ NunV^y, 1860, pp. .TSI rl ii«/. 



