the labours of previous writers, yet I have, in every 

 instance, accepted their assertions only after I had tested 

 them, and found them to be correct. 



To the members of my profession, I am deeply indebted. 

 When they knew the subject on which I was engag-ed, 

 each volunteered to aid me, and generously gave me the 

 benefit of that experience, which personally I was unfor- 

 tunate in not possessing. It was acknowledged, that upon 

 the teeth, some work which might be depended upon, was 

 sadly needed, and to render the present worthy of the 

 confidence of the public, all to whom I applied cheerfully 

 gave their utmost help. From their cordial communications 

 and disinterested co-operation, I learnt much, and gained 

 many valuable ideas. 



16, Spring Street, 



Westbourne Terrace. 



