MEASURING THE EARTH'S SURFACE. 255 



nets should extend over the whole area of each country. Neither the 

 topographical necessities nor the scientific requirements make such a 

 complete geodetical survey indispensable. Those countries possessing 

 a comparatively larger territory would find a complete triangulation 

 too costly and too slow. Each country has therefore laid its nets as 

 it thought best. The Atlantic countries, France and Spain, have laid 

 a series of parallel nets from north to south, and another from east to 

 west, crossing each other almost at right angles. Supposing each of 

 these nets to be drawn on the map, but instead of the various triangles 

 a thick black line to be laid down as a sort of central line of each sep- 

 arate net, the whole systems would have the appearance of square 

 grates or pigeon-holes. Germany and Austria have not observed the 

 same rule ; their lines are less regular in form, although just as con- 

 venient for the purpose. Italy and the smaller states have found it 

 necessary to cover their whole territory, on account of their irregular 

 geographical form, or their smallness. Sweden and Norway have run 

 several nets, and also Russia ; but the vast area to be covered leaves 

 a thorough and systematic triangulation of the whole country out of 

 the question. 



The control which observations extending over such a vast area 

 permit is very great. The possibilities of its being extended over a 

 still wider field are only limited by political difficulties and by the 

 great cost necessary for its execution in half-civilized countries. The 

 result of the work undertaken by the International Commission can 

 not fail to be of the highest scientific value, and the standing of the 

 men who compose it is a guarantee that the greatest efficiency and 

 thoroughness characterize the work done. 



Of the calculations necessary, and which follow the field-work, the 

 least said the better. To an outsider, one who is incapable of compre- 

 hending the scientific purpose of the same, they look very much like 

 time wasted and which could have been better employed. It will suffice 

 to say that all calculations are made twice and independently of each 

 other. Each set of calculators do their work independently of the 

 other, and only compare the final result. Months and months elapse 

 before a partial result is reached, and before other and more compli- 

 cated calculations can be begun. But the battle-field is one worthy of 

 man ; he has arrayed himself against figures, and, although slowly, he 

 conquers them with the help of formulas, equations, and logarithms, 

 all children of his fertile brain. The scientific result is obtained with 

 scientific means. From beginning to end, geodetical triangulation is 

 purely scientific ; nothing is left to chance, and, although it can not by 

 any means be mathematically precise, it comes as near the point of 

 complete correctness as it is possible for any human thing to be. 



