82 POPULAR ERRORS. 



therefore, in common with liis co temporaries, shared in most of the 

 errors which then prevailed concerning the objects of that science. 

 And what is true in regard to the mistakes which the uninstructed 

 may fall into, in reference to the true natm-e of the objects known to 

 the chemist, is true also in respect to those errors, which the uninformed 

 may entertain on other branches of human knowledge. Of these 

 none are more important, or exert a greater influence on the well-being 

 of mankind, than those which relate to our physical condition, and to 

 the agents by which that condition is affected. 



Before the time of Harvey and Lord Bacon, and unhappily long 

 after it, the lessons taught in the schools of medicine, were as foreign 

 to the science pertaining to medicine, as were the dreams of the 

 -Alchemists, to the facts and deductions of the modem chemists ; and 

 though it be true, that many of the errors relating to the objects of 

 general science, have been greatly coiTected in the public mind, by the 

 knowledge incidentally acquired through the public press, and the 

 other multiplied means of instruction, it is not so, or only very par- 

 tially, in respect to those en-ors which relate to our physical condition, 

 because the subject lies out of the course of common reading and 

 enquiry ; and the public mind being unenlightened on the facts which 

 should coiTect its en*ors, the errors continue to prevail. Hence, like 

 the illustrious Newton in reference to the facts and deductions of modem 

 chemistry, men themost enlightened are found to partakeof the errors of 

 the multitude ; and if some of those errors are unimportant when acted on, 

 and serve, perhaps, only to excite a smile, there are others of these 

 errors which exert an injurious influence upon mankind, and materially 

 tend to multiply and aggravate their sufferings. But whether gen- 

 erally unimportant or othei*wise, error is still error ; and like darkness 

 to the traveller, is assistant to other causes in leading its victims astray. 

 Besides, it is not befiting an enquirer after truth to pause in his pur- 

 suit, that he may first measure the precise amount of evil incident 

 to any eiTor ; but as he may justly regard every error as an evil, so he 

 will consider every fact that can dissipate it as a good, and will cast it 

 as a mite into the general treasury of knowledge, that he may thereby 

 assist in promoting the interests of truth, and, by forwarding the pro- 

 gress of human improvement, increase the happiness of his species. 



The enors of a popular kind which relate to our physical condition, 

 and to the agents affecting it, may be divided into those which are 



