TO 



SIR JOHN PRINGLE, BAKT., 







PHYSICIAN TO HER MAJESTY. 



SIR, I have taken the liberty to address you upon this 

 occasion, not so much that I might pay a compliment to your 

 merit, as that I might boast of your friendship : it is im- 

 possible that I should add anything to your reputation by 

 displaying your abilities ; but you may add greatly to mine, 

 even by detecting my mistakes. You have done me the 

 honour to approve this little Essay, and I am ambitious to tell 

 the world that it owes much both to your knowledge and 



your kindness ; which have concurred to suggest many useful 





 hints and judicious corrections, that make it more worthy of 



attention, and afford me a public opportunity of assuring you 

 that I am, with the truest respect and esteem, 



Sir, 



Your most obedient, 



And most obliged humble servant, 



WILLIAM HEWSON. 



