ADVERTISEMEN'T. 



The "Toner Lectures" have been instituted at Washington, 

 D. C, b}' Joseph M. Toner, M.D., who has placed in charge of 

 a Board of Trustees, consisting of the Secretary of the Smith- 

 sonian Institution, the Surgeon-General of the United States 

 Army, the Surgeon-General of the United States Nav}', and 

 the President of the Medical Society of the District of Colum- 

 bia, a fund, "the interest of which is to be applied for at least 

 two annual memoirs or essays relative to some branch of medi-' 

 cal science, and containing some new truth fully established by 

 experiment or observation." 



As these lectures are intended to increase and diffuse knowl- 

 edge, they have been accepted for publication by the Smith- 

 sonian Institution in its "Miscellaneous Collections." 

 JOSEPH HENRY, 



Secretarij Smithsonian Institution. 



Smithsonian Institution, 



Washingtor, August, 18T4. 



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