i28 THE POPULAR SCIENCE MONTHLY 



sense. Isolated, theory would be empty, experiment would be blind; 

 each would be useless and without interest. 



Maupertuis therefore deserves his share of glory. Truly, it will not 

 equal that of Newton, who had received the spark divine ; nor even that 

 of his collaborator Clairaut. Yet it is not to be despised, because his 

 work was necessary, and if France, outstripped by England in the seven- 

 teenth century, has so well taken her revenge in the century following, 

 it is not alone to the genius of Clairauts, d'Alemberts, Laplaces that she 

 owes it; it is also to the long patience of the Maupertuis and the La 

 Condamines. 



We reach what may be called the second heroic period of geodesy. 

 France is torn within. All Europe is armed against her ; it would seem 

 that these gigantic combats might absorb all her forces. Far from it; 

 she still has them for the service of science. The men of that time re- 

 coiled before no enterprise, they were men of faith. 



Delambre and Mechain were commissioned to measure an arc going 

 from Dunkirk to Barcelona. This time there was no going to Lapland 

 or to Peru; the hostile squadrons had closed to us the ways thither. 

 But, though the expeditions are less distant, the epoch is so troubled 

 that the obstacles, the perils even, are just as great. 



In France, Delambre had to fight against the ill will of suspicious 

 municipalities. One knows that the steeples, which are visible from so 

 far, and can be aimed at with precision, often serve as signal points to 

 geodesists. But in the region Delambre traversed there were no longer 

 any steeples. A certain proconsul had passed there, and boasted of 

 knocking down all the steeples rising proudly above the humble abode 

 of the sans-culottes. Pyramids then were built of planks and covered 

 with white cloth to make them more visible. That was quite another 

 thing : with white cloth ! What was this rash person who, upon our 

 heights so recently set free, dared to raise the hateful standard of the 

 counter-revolution? It was necessary to border the white cloth with 

 blue and red bands. 



Mechain operated in Spain; the difficulties were other; but they 

 were not less. The Spanish peasants were hostile. There steeples were 

 not lacking: but to install oneself in them with mysterious and per- 

 haps diabolic instruments, was it not sacrilege? The revolutionists 

 were allies of Spain, but allies smelling a little of the stake. 



"Without cease," writes Mechain, "they threaten to butcher us." 

 Fortunately, thanks to the exhortations of the priests, to the pastoral 

 letters of the bishops, these ferocious Spaniards contented themselves 

 with threatening. 



Some years after, Mechain made a second expedition into Spain : he 

 proposed to prolong the meridian from Barcelona to the Balearics. This 

 was the first time it had been attempted to make the triangulations 



