PHILOSOPHICA 
T R A C T I O N S. 
June 20. 1684- 
The CONTENTS 
I . ^ Letter from Mr, T. Robinfoii to Dr. M. L. concern- 
ing the Bridge at St. Efprit in France, 2. ^4bjiratl 
of a Letter from Mr A. Leewenhoeck of Delft concern'- 
ing Scales within the Mouthy, the Scaly Child that mas 
Jhewny the Anatomy of the Slime within the Guts, and 
the uf e thereof, 3 . "Two Letters formerly written t9 Mr.H^ 
O, by Dr, MX. jJL concernmg fome very Aged Perfons in 
the North of England, id. about the ProjeBion of the 
Threads of Spiders, of Bees breeding in Cafes made of 
Leaves^ of a Viviparous Fly, and of great numbers of 
Maggots obfervedat the time of the Plague, J. D, 1666^ 
4. defcription of a monftrons Child, s- A Letter 
from the learned Malpighius^o Dr. Spon, concerning a 
Horn hanging at the nec\of an Ox j as alfo concerning a 
Kidney of an unufual Shape andTexture, taken out of the 
body of a Man j together with fome Obfervations concern^ 
ing Horns and Glandules in general, 6. A Letter 
from Mr, Charles Leigh of Bra^en-Nofe College in 
Oxon. to the Publijher of thefe Tracts concerning fome 
Experiments and Obfervations about the Natron of E- 
gypt, and the Nitrian Water. An Account of a 
Bool^, Tut a ac efficax LVIS FENE1{Ej£ , f^pe abjque 
Mercurio, ac femper abfqiie Salivatione Mercuriali, 
curandm methodus^ Author e Davide Abercromby M, D. 
Lond. inOetdLV, 1684. 
^ A A Let' 
