PRESIDENTIAL ADDRESS 



ON 



THE ECONOMY OF MOVEMENT 

 By Professor J. S. MACDONALD, B.A., F.R.S. 



[Delivered, October 16th, 1916.] 



As no doubt is usual, but none the less necessary, I should 

 like to express my pleasure in appearing for one year as the 

 President of this Society, which has now for long been known 

 as one of the most energetic centres of work and interest in 

 Biological Science. The encouragement it supplies travels 

 much further than to Liverpool and the immediate district. 

 In Sheffield, for example, I have frequently heard my friend 

 Mr. Arnold Watson, and others, express gratitude for stout 

 support, both from the Society and from Professor Herdman, 

 who perhaps will pardon me when he finds himself described 

 as the vertebral column of this Society. Indeed, I would like 

 very much to be allowed to say how much I am, personally, 

 indebted to Professor Herdman. It mil be accepted as true 

 that an investigation of economy is not without expense, and 

 considerable expense, and there have been times when, pur- 

 suing such an investigation, I have had to encounter and deal 

 with such expenses that friendly support was of the utmost 

 value. In such circumstances I am proud to say I have received 

 most valuable support from Professor Herdman, and that, 

 indeed, without, at the time, being aware of it. If the whole 

 of the membership of this Society is similarly united to its 

 backbone, then there is here a unity of a remarkable kind, 

 which should not escape mention. 



And now to deal with the " Economy of Movement." 

 What I would like to do, would be to explain how anyone 

 possessed of a certain length of limb, and a certain body-weight 

 and weight of limb, should best set about the performance of 



