T O 
Sir HANS SLOANE, Bar'. 
Phyfician in Ordinary to his M a j e s t y,, 
Late President of the Royal College of Physicians^^ 
London, and of the Royal Society. 
Honoured SI 
U F F E R me to caft this weak Eflay (towards 
Natural Knowledge) into your boundlefs Trea- 
fury of Nature, that it may be fupported b)r 
your Charitable Protedlion, and skreen’d under 
your Illuftrious Name from the Malice of Detraftors. If 
there be any Thing in it worthy your Notice, it is prin¬ 
cipally owing to your Generofity, in giving me all poffible 
Encouragement in the Art of Defigning after Nature, in 
which Employment you have ( without fparing your 
Purfe) continued me for many Years, to my great Im¬ 
provement in that Art: Yet, Sir, your indulgent Kind- 
nefs, in giving me a full Liberty at all Times, for thefe 
many Years paft, to confult and examine that ineftimable 
Treafure of Nature and Arts, collected by the worthy In- 
duftry and Labour of a great Part of your Life, engages; 
my Gratitude more than any mercenary Confiderations. 
I have often refledfed on my own good Fortune^, 
when I have confidered that the Benefit which I enjoy has. 
for- 
