C 3 8 ? ] 
<c prkvfquam extenfio fafta vidcatur. Quinetiam ubi 
“ invctcraverint, hsec Tola repofitio reftituere potefl, 
“ nifi jam temporis lapfu caro quidem articuli cavi- 
“ tatem occupaverit, & brachii caput locum in quern 
tc declinavit, confuetudine tritum jam fibi fecerit; 
<£ enimvcro tamch ita inveteratum brachii luxurn 
" reponere mihi pofle videtur. Quid non enim jufla 
“ molitio movcat? Non tamen loco manere pofle 
“ exiflimo, fed, ut confuevir, prolapfurum. ” Loco 
citato . 
One of the greateft Surgeons of our Age fM. 
Petit) in his Treatife of the Difeafes of the Bones, 
was fenfible of all the Perfections of the Ambe of 
Hippocrates : He acknowledges with that Father of 
Surgery, that this Machine has a Sufficient Force , and 
is more than fufficient that it makes an Exten - 
Jion and a Count er-extenfion equally Jlrong He 
even adds that the Arm is placed there as it ought 
to be , in order to relax the Mufcles , or at leaft ft retch 
them equally , which is the Fourth Rule the Author 
propofes to be obferved,^. 42. in making the Exten- 
sion and Counter-extenlion. But at the fame time 
M. Petit does not diflfemble fome eflential Defects he 
finds in this Invention, and which, without doubt, 
were unknown to Hippocrates . 
The capital DefeCt in this Ambe is, that it pufhes 
the Head of .the Bone into its Cavity , before the 
Extenfion and Count er-extenfton are made. The 
dangerous Confequences of this DefeCt, are, accord- 
ing to M. ‘Petit , ift ? That the Reduction is very 
difficult, becaufe the Bone is not conducted by the 
fame Way it took in luxating itfelf, and that one 
meets with Obstacles from the Parts' that furround it, 
even 
