SCIENCE. 



[N. S. Vol. XVII. No. 435. 



of this class of Avorks, and the latest de- 

 velopments which have proved the prac- 

 ticability of a new form of tool for securing 

 results by the utilization of the principle 

 of reaction, instead of velocity and con- 

 centration by means of two jetties. It 

 also emphasized the inability of currents 

 of fresh water to scour to sufficient depths 

 when buoyed up by the heavier salt water 

 which obstructs and raises them on their 

 path over a bar and the greater specific 

 gravity of the wave-driven sand, or littoral 

 drift, of which the bars of tidal inlets are 

 composed. The location and cause of the 

 abnormal depths found in gorges or under 

 the lee of obstacles, and the resultant 

 counter-scarps, illustrated by numerous 

 slides showing the proper position and 

 form to secure a continuous channel across 

 an obstructing bar at half the cost of the 

 usual devices, and by natural forces which 

 will maintain the channels which they 

 carve. 



The above general claims and principles 

 were illustrated and confirmed as to their 

 value by a practical demonstration on a 

 large scale of incompleted work on the 

 coast of the Gulf of Mexico, which has 

 proved to be remarkably permanent and 

 effective. 



Afternoon Session, 2 o'clock. 

 Vice-President Barker in the chair. 



The Curtis Steam Turbine: Mr. W. L. R. 

 Emmet, of Schenectady, N. T. 



The Principle of Least Work in Mechanics, 



and its Possible Use in Investigations 



Regarding the Ether of Space: Professor 



Mansfield Mereiman, of Bethlehem, Pa. 



The use of this principle in engineering 



computations was briefly explained. It was 



pointed out that its application is only 



valid in the case of bodies that are perfectly 



elastic and that its successful use in the 



determination of stresses in indeterminate 



structures depends upon this assumption. 

 If the ether of space be perfectly elastic it 

 is probable that the principle of least work 

 can be applied to determine the stresses 

 which accompany the action of gravitation, 

 and an effort is being made in this direc- 

 tion, the results of which appear to indi- 

 cate that the ether has properties in some 

 respects unlike those of elastic bodies. 



The Nernst Lamp (with experimental dem- 

 onstration) : Mr. Alexander Jay Wukts, 

 of Pittsburg. 



The Problem of the 'Trusts': Mr. C. 

 Stuaet Patterson, of Philadelphia. 



An Inquiry into the Relation between the 

 Objective Operations and Events Re- 

 vealed to Us by the Scientific Study of 

 Nature, and the Corresponding Actual 

 Operations and Events Which are What 

 Have Taken Place in the Universe of 

 Real Existences: Professor G. John- 

 stone Stonet, F.R.S., of London. 

 Hitherto every attempt to ascertain the 

 events that are actually happening in the 

 universe of real existences— in other words, 

 the study of ontology— has been pursued 

 almost exclusively from the human stand- 

 point of the metaphysician. This limited 

 mode of treatment has led to a few nega- 

 tive results, which are chiefly of value by 

 helping to dispel popular errors ; but it has 

 established little that is positive, or that 

 can be of service to the scientific student 

 of nature. And yet the scientific investiga- 

 tion of nature has led us in more than one 

 direction into contact with problems of 

 ontology — as when physiology brings us 

 face to face with such a fact as that there 

 is some interpendence between the thoughts 

 that are our mind, and objective events 

 going on in our brain. What help has 

 ontology rendered in a ease of this kind, or 

 throughout our studies in physics, when 

 we make any attempt to penetrate to the 

 causes of the events that occur? In fact. 



