sict. ii.J. DISSERTATION SECOND. 53 



examples of its use, exhibited for several ages little else than 

 a series of illusory pursuits, or visionary speculations, while 

 now and then a fact was accidentally discovered. 



Under the influence of these circumstances arose Para- 

 celsus, Van Helmout, Fludde, Cardan, and several others, 

 conspicuous no less for the weakness than the force of their 

 understandings : men who united extreme credulity, the 

 most extravagant pretensions, and the most excessive vani- 

 ty, wilh considerable powers of invention, a complete con- 

 tempt for authority, and a desire to consult experience ; 

 but destitute of the judgment, patience, and comprehensive 

 views, without which the responses of that oracle are never 

 to be understood. Though they appealed to experience, 

 and disclaimed subjection to the old legislators of science, 

 they were in too great haste to become legislators themselves, 

 and to deduce an explanation of the whole phenomena of 

 nature from a kw facts, observed without accuracy, arrang- 

 ed without skill, and never compared- or confronted with 

 one another. Fortunately, however, from the turn which 

 their inquiries had taken, the ill done by them has passed 

 away, and the good has become permanent. The reveries 

 of Paracelsus have disappeared, but his application of che- 

 mistry to pharmacy has conferred a lasting benefit on the 

 world. The Archceus of Van Helmont, and the army of 

 spiritual agents with which the discovery of elastick fluids 

 had filled the imagination of that celebrated empirick, are 

 laughed at, or forgotten ; but the fluids which he had the 

 sagacity to distinguish, form, at the present moment, the 

 connecting principles of the new chemistry. 



Earlier than any of the authors just named, but in a great 

 measure under the influence of the same delusions, Roger 

 Bacon appears to have been more fully aware than any of 

 them of the use of experiment, and of mathematical reason- 

 ing, in physical and mechanical inquiries. But, in the thir- 



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