52 INTRODUCTORY ADDRESSES. 



will be swept along by the great tropical streams towards the poles, and 

 will visit the difterent latitudes successively as do the storms of rain, and 

 many other changes of the weather. Nor must we forget to take into 

 the account the strong local agency of islands, coasts, and soils upon 

 the air, by which also every atmospheric disturbance is greatly modified. 



The conclusion seems, therefore, to be quite as probable as any other 

 that has yet been oflered, that those regular changes of the weather un- 

 der discussion are produced by the influence of the moon upon our at- 

 mosphere. 



Gettysburg, Dec. 24:th, 1844. 



INTRODUCTORY ADDRESSES, 



Delivered at the Commencement of the Course of Instruction in the Medical Department of Penn- 

 sylvania College, Philadelphia, November, 1844. 



The Medical Department of Pennsylvania College, Gettysburg, is lo- 

 cated in the city of Philadelphia. It has recently been re-organized un- 

 der very flattering prospects. The faculty is now complete, and the va- 

 rious branches of medical science provided with instructors, known to 

 the profession and the public, and known as honorable and high mind- 

 ed men, qualified by their talents and education to instruct students of 

 medicine in the important science of curing disease. These addresses, 

 four in number, are creditable to their aiithors, as literary performances, 

 and each one discusses an important theme. It is small praise to say, 

 that every professor has accomplished his task with ample learning and 

 in an instructive and judicious manner. The lecture* of Dr. Darrach, 

 who occupies the chair of Theorv and Practice of Medicine, is a learn- 

 ed disquisition in the history of medical science, and the true basis of 

 medical philosophy. Maintaining that the science is founded in obser- 

 vation and induction, and not in ingenious speculation without sufficient 

 data, it shews that, from the time of Hippocrates, the lather of medicine, 

 ad nostra tempora, those who have trod in his footsteps, and worshipped 

 at the shrine of nature, have rendered by their discoveries the most es- 

 sential service to science, whilst the visionary and speculative, led on 

 by the celebrated Galen, have dazzled and been adored, but their reign 

 was not perpetuated. Truth would seem to be led captive — when 

 sought by the Baconian, or Hippocratic method — as well in medicine, 

 as in ph3'sics and metaphysics. 



It is diflicult to repress an expression of regret, that a discourse so 

 elaborate and beautiful, should have suflered so seriously in the hands of 



* Introductory to the course of Theory and Practice of Medicine. 



