304 THE COMING OF MAN 



understand the mighty unseen force which keeps 

 each planet in its course, and holds all the vast 

 systems of suns and worlds to regular paths and 

 orbits. 



These men, and those who came after them, who 

 spent their lives searching for truth, have found how 

 the earth and the planets move, and they can tell 

 just where in the sky they will be at any time. You 

 have only to see a page of the neat little figures with 

 which these thinkers calculate the orbits of the 

 planets, to be filled with wonder at the power that 

 God has given to the human mind; for these men 

 have gone beyond the world with their thought, and 

 they have proved the truth of things that they can 

 neither touch, nor feel, nor see. 



They seem so far above ordinary mortals that we 

 look up to them with amazement; they seem like 

 different beings from us. But no! They were chil- 

 dren once, looking just like ordinary children. Some 

 of them were delicate and sickly ; some were poor, so 

 poor that they had to work hard at their daily tasks 

 before they could begin to do the work they loved 

 and dreamed of day by day. Some of them were well 

 educated in the schools, but others gained by them- 

 selves from books and experiments that knowledge 

 which led them on to success. 



Many of these boys had mothers whose love and 

 ambition for them made them what they were. Some 

 had sisters, daughters, and nieces, without whose 

 patient and loving help they could not have suc- 

 ceeded. And many of these wonderful minds be- 

 longed to women: Maria Mitchell, the astronomer, 



