EULOGY ON PROFESSOR ALEXANDER DALLAS BACHE. 371 



affection which he had always borne to his native city, whither it was his 

 cherished intention to return when he should be at last released from offi- 

 cial duty. At the request of the governor of Pennsylvania, although over- 

 whelmed with other publicjabors, he planned lines of defenses for Philadel- 

 phia, and to a certain extent personally superintended their construction. 

 Unaccustomed for many years to direct exposure to the sun, this work 

 proved too much for his physical strength and brought on the first indica- 

 tions of that malady which terminated his life. Though apparently of 

 a vigorous constitution, and capable, under the excitement of official 

 life, of bearing an unusual amount of bodily fatigue, yet he was subject 

 at intervals to "sick headaches," a disease which seems to have been 

 hereditary, and which perhaps conspired with other causes in termi- 

 nating his useful and distinguished career. Previous to the war he had 

 spent the warmer part of each summer in a tent, at some point of the 

 primary triangulation of the survey, whence he directed the various 

 parties in the field by correspondence ; and as the point was usually at 

 the top of a mountain, or at some elevated position, from which other 

 stations of the survey could be seen, he did not want for invigorating 

 air. With this, and the exercise of measuring angles he laid in a store of 

 health sufficient to enable him to carry on without interruption the 

 arduous duties of the remaining portion of the year. But after the com- 

 mencement of the war his presence was continually required in Wash- 

 ington to give advice and information as to military and naval opera- 

 tions, and to attend the meetings of the scientific commission to which 

 we have previously referred. He was, therefore, no longer able to avail 

 himself of the recuperating influence of mountain air, and in view of this 

 his valuable life may be said to have been one of the sacrifices offered 

 for the preservation of the Union. The first indications of the insidious 

 disease which gradually sapped the citadel of life were numbness in the 

 fingers of his right hand, and, on one occasiou, for a short time only, 

 loss of memory. Though these symptoms gave him some uneasiness, 

 they did not diminish his exertions in the line of his duty. Other symp- 

 toms, however, exhibited themselves, which, though awaking anxiety, 

 did not much alarm his friends, until he was suddenly deprived, in a con- 

 siderable degree, of the power of locomotion and of the expression of 

 ideas ; the result, it was supposed, of a softening of the brain. But though 

 thepowerof expression was paralyzed, his memory appeared to retain all 

 the impressions of the past, and he evidently took much pleasure in hav- 

 ing recalled to him scenes and events of years gone by. For several months 

 he was very anxious as to the business of the Coast Survey, and it was 

 with difficulty he could be restrained from resuming in full the duties of 

 his office ; but as the malady increased his perception of external objects 

 diminished. He took less and less interest in passing events, and finally 

 seemed to withdraw his attention from the exterior world, with which 

 he almost ceased thenceforth to hold any active communication. It was 

 hoped that a voyage to Europe, through the excitements of shipboard 



