Inquiry into the Laws of Affinity^ 97 



In the human ear, and in that of birds, the radiated fibres of the membrana tympani 

 have their principal attachment to the extremity of the handle of the malleus, which it 

 nearly in the centre of the membrane. 



In the membrane of the elephant, which is oval, the attachment to the handle of the 

 malleus is at fome diftance from the centre. In the horfe, deer, and cat, which have 

 the membrane dill more oval than the elephant, the handle of the malleus is fituated in 

 the long axis of the membrane, with its extremity extending beyond the centre, reaching 

 nearer to the circumference ; and the fibres of the radiated mufcle are not only attached to 

 its end, but alfo laterally to nearly the whole length of its handle. 



This oval form of the membrana tympani, in thofe quadrupeds, and the very extenfivc 

 attachment of the fibres of the radiated mufcle to the handle of the malleus, may be the 

 reafon why their ears are not equally fitted to hear inarticulate founds, as the ears pf birds 

 and of man. 



Should this radiated mufcle of the membrana tympani (which is probably the fmalleft in 

 the body that has a diflinft aftion) be thought too infignificant to have an office of fo much 

 confequence afligned to it, let it be remembered, that the fize of mufcles is no indication 

 of their importance, but only of the refiftance to be overcome by their a£tion ; and that 

 the more delicate actions are performed unlverfally in the body by very fmall mufcles, of 

 which the iris in the eye furnifties a very confpicuous example. 



{To he continued.') 



IV. 



Inquiries relative to the La-ws of Affinity^ by CiT. Bertbollet, Member of the National 



Injlitute of Arts and Sciences*. 



f Concluded from, page 6g.J 



ARTICLE XIII. 



On the Precipitation of Metallic Solutions by other Afetals. 



..w. 



HEN the metals are precipitated by a fubftance which does not feize their oxigcn, 

 the precipitates retain part of the acid, and often part of the precipitant. 



We have a ftriking inftance of this divifion, which then takes place in the precipitate of 

 the oxigenated muriate of mercury, by the fixed alkalis, ammonia and lime. On expofing 

 the precipitate to a fufficient heat, a more or lefs confiderable portion of mercury, accord- 

 ing to the nature of the precipitate, is reduced, another is fublimed, and forms a muriate, 

 not becaufe the muriatic acid is found combined only with a portion of the oxide of mer- 



• TranHation from the Annales de Chimie, XXXVII. 151, 



Vol. v.— June i8of. O cury. 



