PRINCIPLE OF LEAST ACTION 89 



work with the least quantity of material, and their forms 

 are precisely those which the principle of least action 

 takes in muscular mechanics". 



The first thing to do in investigating this subject was 

 to obtain the " coefficient " of muscular force, which 

 represents the number of lbs. weight necessary to break 

 the muscle across, as if it were a rope. Dr. Haughton, 

 by an elaborate series of experiments, found that " 947 

 lbs. per square inch is the weight that the arms of a 

 young man accustomed to athletic exercises are capable 

 of lifting. iiO'4is the corresponding coefficient for the 

 muscles of the legs of a similar class, and 107 for the 

 muscles covering the abdomen." 



In concluding his first of three lectures Dr. Haughton 

 observes: "I have shown you that a planet moves in its 

 orbit as a lazy intelligent creature would, who was anxious 

 to perform an allotted task with the least trouble to itself; 

 that the bee constructs its wonderful cell so as to produce 

 a given amount of storage for its honey with the least pos- 

 sible amount of trouble to itself Similarly, I will show 

 you how the tendons of the legs and arms of animals are 

 constructed with a wonderful economy of the same kind 

 as that with which the bee constructs its cell. ... Is it 

 by the intelligence of the planet that it moves in its orbit ? 

 Who has weighed out and regulated the weight of the 

 tendons of our arms and hands ? By what force or by 

 what intelligence do the limbs of animals describe their 

 proper paths ? Who places the socket of each joint in 

 the exact position (which can be calculated with un- 

 erring certainty by mathematics) which enables the 

 muscle to perform its allotted task with the least amount 

 of trouble to itself?" 



The answer which the Doctrine of Evolution by self- 

 adaptation gives is, that protoplasm at once responds to 



