3904.) 
this remark a place in my Paper, was to 
explain, by help of it, an apparent imper- 
feétion in the fenfe of hearings But he 
has overlocked the paragraph laft cited, 
from motives of lazinefs, o1 a with. to mif- 
reprefent ; for he makes. my exvlanatioa 
of the faculty whereby men judge of the 
elevation of founding bodies, to be con- 
nected with the unequal powers of the 
before-mentioned fenttbility, which are 
found to obtain in different parts of the 
head. After making this falie ftlatement, 
he pronounces the whole to be hypothe- 
tical, and palpably untrue, but does not 
deicribe the natufe of the myiterious con- 
nedlion, which fhould have been done, in 
his own words, for obvious :eafons. 
The explanation of the phenomenon, 
as it ftands in the Edinburgh Review, is 
hypothetical and untrue ;. but then the 
hypothelis is not mine; at belt it is a ne- 
gligent “blunder of the Reviewer. My 
explanation is at page 641 of the fifth vo- 
lume of the Manchelter Memcirs, and 
may be briefly ftated in the foliowing 
manner: . 
The topical irritation produced by a 
given found, 1s imprefled on a particular 
portion of the head; the fituation of 
which is known to the hearer in confe- 
quence of his intimate acquaintance with 
the external firucture of this member. 
He alfo kiiows (o what part of the hea- 
vens the portion thus excited is.dirested at 
the time ; and experience has. taught him, 
that the quarter to which it points is the 
place cf the found. - 
An experiment was Omitted in the Ef- 
fay I am defending, which is new offers 
ed to the public’ through the medium 
of your Journal, becaufe it feems to 
prove the relative places of founds to be 
difcovered by the co operation of the ears 
and external teguments of the head. Let 
a man provide two tubes, which are open 
at both ends, and fufficiently wide to res 
ecive his ears ; after adjuliing them to 
the oppofite fides of his head, let him ata 
tend to a found whieh is eontinuous and 
ftationary, taking care at the {ame time 
toturn and oend his neck, fo as to place 
the tubes in vanous p fitions relative to 
the founding body. What wiil- be the 
rational event of ihe exper:ment, on the 
fuppofition that the fenfibiiiy is smagi- 
nary; which I have aferbed to tne exier- 
nal tegumenis ?. All the pulfes capable of 
exciting lenfaison in this particular cafe, 
will evidenily arrive at the organs of 
hearing in patns which are parallel to the 
two tubes ; coniequently tha: tube which 
receives the ftronger vibrations trem the 
Montury Mas. No. 115. 
~ 
On the Manifaéture ana Quality“of Chefdire Salts 
44 
fource of the found, will indicate it to be 
fituated imits own axis produced ; juft as 
an ear placed in @ narrow paflage, fup- a 
pofes founds to move indiferiminat ly in 
the direftion of that paffage. This is 
the genuine conclufion from the premifes, 
but icis falfe 5; for the ufe of the tubes 
does not prevent a perfon from diicovere 
ing the place of a found. On the contra= 
ry, when a man introduces bis head into 
a narrow paflage, he thereby loles this 
power of dilcrimination. What reply 
can the oppofeis of my theory make to 
thefe faéis? 
After tracing the primary objedt of the 
Eflay to phyfical principles, I have drawn 
the following corollary from it. Ifa 
ventriloquilt can perfuade a byfancer that 
his voice comes from an object not in the 
Fight line joining their perfons, the latter 
docs not hear the fpeaker’s voice, but an 
echo of it. This corollary is -rejecied by 
the Keviewers, apparently to make way 
for a morai hypethefs. Though this 
writer admits my theory of direé&t and ob- 
ligue hearing, he imprudently maintains 
that the hearer’s expeétation is excited by 
the art of the ventidloquift, fo as to fet afide 
the evidence of his ears. If a fedentary 
mechanic be in the habit of hearing a 
clock at the right hand of his feat, can 
the powers of expectation continue the 
delufion when the clock..is removed un« 
known to him? Until this quettion is an- 
fwered in the affirmative, the moral hypos 
thefis muft give place to the phyficai the- 
ory. Joun GouGa. 
Middlefhaw, March 28, 1804. 
} <—— 
To the Editor of the Monihly Magazine. 
SIR, 
A PAPER has jaft beer put into my 
hand, intiled, ‘* Commerce of the 
United Siates with Foreign Parts, in Sea- 
Salt.””> The name of tne author is not, 
given with it ; but it was firtt printed in 
a periodical woik, publithed at New York, 
intiiled *¢ The Medical Repofitory,”’ has 
been fince circulated wish a good deal of 
indultry in America, and appears to have 
excited confiderable attention there. In 
this Paper the yeilow-fever, and the va- 
rieus peltilent:al difeafes which have lon 
been jo prevalent in America, are afcribed 
to the falt brought from Liverpool, which 
is fated to be ‘‘ weak and impure ;” and 
the author. lirongiy imptefles upon his 
countrymen the netefliry of avoiding the 
ule of this ‘* pernicious article of ims 
port,” if they with to efcape thefe inieca 
tious diforders, hat it may not be ima. 
3M gined 
