Royal Societv. 429 
ing both thefe bones together; this tendon by means of its mem- 
branous coat is conneded with the bone on which it is Iprcad : 
The fecond mulcle of the internal ear arifes from a bony tube in 
the lower part of that bone, which lies between the 'Por^a and 
Fenefira of the labyrinth 5 and is much leis and fliorter than the 
monogaltric mulde above delcribed 5 from hence Vieufferis calls it 
the leffer mufcle of the internal ear j it has a thick flefliy belly, 
and is inferted by a very llendcr tendon into the head of the 
Stapes. 
■ Whilfl: the monogaftric mufcle of the car contrafls itfelf, its 
longer tendon raifcs the head of the Malleus and body of the 
IncuSt a little upwards, and but a little 5 bccaufe that the jfhorter 
tendon of that mufcle, as being conne61:ed by its extremity to the 
head of the Malleus as the longer tendon is to its {lender Apo- 
phyjis and neck, is an antagonift to the longer 5 and becaule it is 
connected by its coat to the bone upon which it lies: When the 
head of the Malleus is railed upwards, the extremity of its handle 
is neceflarily deprefled^ and by this means the middle part, to 
which the handle adheres, of the external membrane of the 'lym" 
panum is drawn outwards, and thus its fuperiicies is made plane 
or nearly fo: 'Whilll the tendon of the monogaftric mufcle of the 
ear, and the Malleus perform thefe feveral offices, they extend 
the linall membrane above deicribed, that in fubjed^s, where it is 
found, cuts the exterior membrane of the Tympanum tra.niverie\y ^ 
and it feems in fome meafure to fupply the place of an antago- 
nift to the monogaftric mufcle of the ear, becaufe by its elafticity 
it recovers its natural ftate of tenfion, and with the lame Nifus 
afltfts the exterior membrane of the Tympanumto recover its ten- 
iion and figure, when it is no longer prefled by the extremity of 
the handle of the Malleus: As by railing the head of the Mal- 
leus upwards, the extremity of the handle is inclined a little 
downwards 5 lb alio by railing the Incus upv>/^rds, the extremity 
of its internal ^pophyfis is depreffed a little, and but a little 5 
becaufe the Jncus is io fituated in the cavity of the bone, that 
forms the external rim of the balls of the Tympanum^ that its 
body cannot be railed upwards, but at the lame time its external 
Apophyfii preftes by its extremity upon the bone that is under ir, 
and to which it is very near; hence it is that the monogaftric 
mulcle of the ear cannot by its longer tendon raile the lucus 
much : When the body of the Incus is a little elevated, and its 
internal Jlpopbyp depreiled a little, at the lame time it draws 
with it, andconlequently depreffes a little the head of the Stapes^ 
to which it is conneded by means of the Os knticulare ; and 
whilft 
