Ixv 



Minister at the Court of St. James's. He was born in Philadelphia, on the 

 19th of July, 1806. At an early age he became a pupil of a classical school 

 of celebrity, and was distinguished by unusual aptitude hi the acquisition 

 of learning. Shortly before arriving at the age of fifteen, he was appointed 

 a cadet of the Military Academy at West Point, and graduated in 1825 at 

 the head of his class. 



After graduating, he was selected to remain in the x\cademy as an 

 x\ssistant Professor, and in this position, which gave him an opportunity 

 of reviewing his studies and examining his reading, he continued one year, 

 when at his own request he was assigned to engineering duty at Newport, 

 R.I. Here he remained two years, engaged in constructing fortifications, 

 and devoting his extra hours to the study of Physics and Chemistry; and 

 supported his mother and her younger children out of his stinted pay as 

 Lieutenant of Engineers. An unexpected change now took place in his 

 circumstances, which enabled him to marry. He was appointed to tlie 

 Professorship of Natural Philosophy and Chemistry in the University of 

 Pennsylvania, at Philadelphia. Having had, prior to this, some experience 

 as a teacher, he soon gained the entire confidence of the authorities of the 

 University and the affections of his pupils. He became a member of the 

 Franklin Institute, a Society then newly established for the promotion of 

 the Mechanical Arts. This Society was well calculated to exhibit his 

 talents and develope his character. It brought him into intimate associa- 

 tion with the principal manufacturers, engineers, and artisans of the city. 

 Facilities were thus afforded him for the prosecution of science which he 

 could nothave commanded in any other way. Work:?hops were thrown open to 

 him, and skilful hands offered ready assistance in realizing the conceptions 

 of his suggestive mind. His descent from the illustrious Statesman and 

 Philosopher, whose name the Institution bears, contributed in some de- 

 gree no doubt to the influence which he acquired ; but it was in the main 

 to his own industry, ability, and coiu'tcsy that he owed the favour and 

 distinction which, in assigning to him the principal directorship of scientific 

 investigations, afforded him the means of so greatly contributing to the 

 usefulness of the Society, and of advancing his own reputation. An account 

 of the labours in which he was engaged in his 'connexion with the Franklin 

 Institute will be found in the volumes of its Journal from 1826 to 1835 

 inclusive. The results of his investigations relating to the bursting of 

 steam-boilers, after a lapse of more than thirty years, have not yet been 

 superseded by any others of more practical value. These experiments 

 were attended with no small amount of danger, and required in their 

 execution no small amount of personal courage. 



He erected an Observatory in the yard of his own house, in which, with 

 the aid of his wife and his friend and former pupil, John Fraser, he deter- 

 mined with accuracy, for the first time in the United States, the periods of 

 the daily variations of the magnetic needle, and in another series of obser- 

 vations the connexion of the fitful variations of the direction of the 



VOL. XVI. / 



