144 



THE LAST CRUISE OF THE CARNEGIE 



plankton- and bottom-samples so far collected. Many instru- 

 ments were replaced by new ones sent down from Washington. 

 Others, like the electric recording-psychrometer, needed extensive 

 repairs. Besides this we received here apparatus for the scientific 

 studies which we were now adding to our already full program. 

 The United States Navy had loaned us complete equipment for 



Tablets in Panama City Relating the History of the Building of the Panama 



Canal 



They show tliat it was more a triumph of preventive medicine than of engineering. 



making pilot-balloon observations of air-currents in the upper 

 atmosphere. This equipment included a specially designed 

 theodolite (for measuring horizontal and vertical angles in noting 

 the courses of the balloons as they rise from the deck), hydrogen 

 tanks, balloons, inflation-balance, and computing-forms. 



Captain Ault and Scott were kept very busy reprovisioning the 



