46 



ON THE THEORY OF COMPOUND SOUNDS. 



through a narrow tube, becaufe I do not recollect a circumftance 



of the kind ; nor do I think myfelf bound to determine the 



effect, becaufe an inftance, which is fo particular, can have no 



Fact refpe&lng weight in a difpute concerning a general principle. I am ac- 



bells, of which : , , , . , . „ . • \ . j r 



the founds are quamted, however, with one circumftance which deterves at- 



faidnottoco- tention atprefent: the notes of two or more bells are not 

 obliged to coalefce by palling through the narrow found-holes 

 of (he fleeple of a country church : and if Dr. Young will fup- 

 pofe the point A, in the demonstration of my third proportion,, 

 to be placed in the mouth of his tube, he will fee that the mo- 

 tions of the corpufcle will not be difturbed by the edge of the 

 pipe. The Doctor's anfwer blames my representation of his 

 idea of a compound found, as amounting to a charge of igno- 

 rance in the moft common occurrences. The reprefentation 

 appeared to be a neceflary introduction to the objections which 

 were levelled, in the fequel of my eflay, at the Doctor's theory, 

 not at his experience ; and if the ftatement be not juft, it is dif- 

 ficult to difcover the fenfe of the term coalefcence in that fec- 

 tion of his paper in which the fubject is examined, efpecially 

 when the author infers, that the ftrength of the found in a con- 

 cert is not in exact proportion to the number of inftruments 

 compofing it. The writer of this paragraph, without doubt 

 wifhed his readers to conclude, that the vibrations, which are 

 communicated to the air by a number of founding bodies, re- 

 duce themfelves to a fingle fet of vibrations by mutual opposi- 

 tion : Now my objections to this doctrine mufr, remain in force, 

 until mankind can be convinced that unity pofleffes the quali- 

 ties of number. 



The anfwer corrects the new theory in two effential points : 

 Firjl, It gives a power of analyzing compounds to the ear; but 

 this power cannot be admitted before the doctrine of coalef- 

 cence is eftablifhed: Second, It reduces the coalefced com- 

 pound to a pigmy, and joins to it the powerful reflected parts 

 of its constituents, thereby forming a mixture. A few remarks 

 On the mixture on the range of fuch a mixture fhall clofe this letter. When a 

 of founds differ- traveller approaches a town, he frequently hears the bells in it 

 ranges. at ^e diftance °f f° ur or ^ ve miles ; the beating of a drum may 



catcb his attention at one-third of that diftance ; when near the 

 place, he perceives the blows of hammers, and at laft a mixed 

 ppife. In his journey, then, he meets with a fucceffion of 

 founds at the limits of their refpective ranges, but does not find 



the 



