198 Hature'0 dfciracles. 



ries the lifting-machinery, consisting of block 

 and tackle, able to sustain a weight of fifty 

 tons. Situated at one end of the crane are 

 one or more electric motors, which are able, 

 under the control of the engineer, to produce 

 a motion in any direction, which is the re- 

 sultant of a compound motion of the two cars 

 acting crosswise to each other together with 

 the perpendicular motion of the lifting-rope 

 connected with the block and tackle. It seems 

 like a thing endowed with human reason, when 

 we see it move off to a distant part of the 

 building! reach down and pick up a piece of 

 metal writhing several tons, carry it to some 

 other portion of the building and lower it into 

 place, to the fraction of an inch. While the 

 machine itself does not reason, there is a rea- 

 soning being at the helm, who controls it and 

 makes it subservient to his will. The machine 

 is to the engineer who manipulates it what a 

 man's brain is to the man liiin-clf. The brain 

 is the instrument through which the unseen 

 man expresses his will and impresses his work 

 upon men and things in the visible world. 



