with a better choice awl form of glares, which 
was the tirst I Saw or heard. Being charmed 
with the sweetness' of its tones, and the music 
he produced from it, 1 wished to see the 
glasses disposed in a more convenient form, 
and brought together in a narrower compass, 
so as to admit of a greater number of tones, 
and all within reach of hand to a person sit- 
: ting before the instrument; which 1 aceom- 
! piished, after various intermediate trials, and 
f less commodious forms, both of glasses and 
construction, in the fallowing manner : 
“ The glasses are blown as" nearly as possi- 
I ble in the form of hemispheres, having each 
[ an open neck or socket in the middle. I he 
l thickness of the glass near the brim is about 
the tenth of an inch, or hardly so much, but 
thicker as it comes nearer the neck; which in 
the largest glasses is about an inch deep, and 
\ '<xi\ inch and a half wide within ; these tlimen- 
sions lessening as the glasses themselves di- 
minish in size, except that the neck of the 
smallest ought not to be shorter than half an 
inch. The largest glass is nine inches diame- 
ter, and the smallest three inches. Between 
these there are 23 different sizes, differing 
from, each other a quarter of an inch in di- 
ameter. To make single instrument there 
should be at least six glasses blown of each 
; size ; and out of this number one may pro- 
bably pick 37 glasses (which are sufficient for 
three octaves with all the semitones) that will 
be each either the note one wants, or a little 
sharper than that note, and all fitting so well 
into each other as to taper pretty regularly 
from the largest to the smallest. It is true 
that there are not 37 sizes; but it often hap- 
pens that two of the same size differ a note or 
half a note in tone, by reason of a difference 
in thickness, and these may be placed one in 
the other without sensibly hurting the regu- 
larity of the taper form. 
“‘The glasses being chosen, and every one 
marked with a diamond the note you intend 
it for, they are to be tuned by diminishing 
the thickness of those that are too sharp. 
This is done by grinding them round from 
the neck towards the brim, the breadth of 
one or two inches as may be required, often 
trying the glass by a well-tuned harpsichord, 
comparing the note drawn from the glass by 
your linger with the note you want, as sound- 
ed by that string of the harpsichord. When 
vou come near the matter, be careful to wipe 
the glass clean and dry before each trial, be- 
cause the tone is something flatter when tne 
glass is wet than it will be when dry; and 
grinding a very little between each trial, you 
will thereby tune to great exactness, the 
more care is necessary in this, because it you 
go below your required tone, there is no 
sharpening it again but by grinding somewhat 
off the brim, which will afterwards require 
polishing, and thus increase the trouble. 
“ The glasses being thus tuned, you are to 
be provided with a case for them, and a spin- 
dle on which they are to be fixed. My case 
is about three feet long, eleven inches every 
way wide within at the biggest end, and li . c 
inches at the smallest end; for it tapers all 
the way, to adapt it better to the conical 
figure of the set of glasses. I his case opens 
in the middle of its height, and the upper 
part turns up by hinges fixed behind. 1 he 
spindle is of hard iron, lies horizontally fiom 
end to end of the box within, exactly in tne 
middle, and is made to turn on brass gudgeons 
Von. I. 
HARMONICA. 
; at each end. It is round, an inch diameter at 
the thickest end, and tapering to a quarter 
of an inch at the smallest. A square shank 
comes from its thickest end through the box, 
on which shank a wheel is fixed by a screw. 
This wheel serves as a fly to make the motion 
equable, when the spindle, with the glasses, 
is turned by the foot like a spinning-wheel. 
My wheel is of mahogany, IS inches diame- 
ter, and pretty thick, so as to conceal near its 
circumference about 25ib. of lead. An ivory 
pin- is fixed in the face of this wheel, about 
four inches from the axis. Over the neck of 
this pin is put the loop of the string that conies 
up from the moveable step to give it motion. 
The case stands on a neat frame with four 
legs. 
“ To fix the glasses on the spindle, a cork 
is first to be fitted in each neck pretty tight, 
ami projecting a little without the neck, that 
the neck of one may not touch the inside of 
another when put together, for that would 
make a jarring. These corks are to be perfo- 
rated with holes of different diameters, so as 
to suit th 'at part of the spindle on which they 
are to be fixed. When a glass is put on, by 
holding it stiffly between both hands, while 
another turns the spindle, it may be gradually- 
brought to its place. But care must be taken 
that the hole be not too small, lest in for- 
cing it up, the neck should split; nor too 
large, lest the glass, not being firmly fixed, 
should turn or move on the spindle, so as to 
touch or jar against its neighbouring glass. 
The glasses thus are placed one in another ; 
the largest on the biggest end of the spindle, 
which 'is to the left hand : the neck of this 
glass is towards the wheel; and the next goes 
info it in the same position, only about an inch 
of its brim appearing beyond the bnm ot the 
first ; thus proceeding, every glass when fixed 
shews about an inch of its brim (or three 
quarters of an inch, or halt an inch, as they 
grow smaller) beyond the brim of the glass 
that contains it ; and it is from these exposed 
parts of each glass that the tone is drawn, by 
laying a finger on one of them as the spindle 
and glasses turn round. 
“ My largest glass is G a little below the 
reach of a common voice, and my highest 
G, including three complete octaves. I o 
distinguish the glasses more readily by the eye, 
I have painted the apparent parts of the 
glasses within side, every semitone white, and 
the other notes of the octave with the seven 
prismatic colours; viz, C, red; I), orange; 
E, yellow; F, green ; G, blue;* A, indigo; 
B, purple; and C, red again; so that the 
glasses of the same colour (the white except- 
ed) are always octaves to each other. 
“ This instrument is played upon by sitting 
before the middle of the set of glasses, as be- 
fore the keys of a harpsichord, turning them 
with the foot, and wetting them now and then 
with a spunge and clean water, dhe fingers 
should be first a little soaked in water, and 1 
quite free from all greasiness ; a little fine 
chalk upon them is sometimes useful, to 
make them catch the glasses and bringout the 
tone more readily. Both hands are used, by 
which means different parts are played to- 
gether. Observe, that the tones are best 
drawn out when the glasses turn from the 
ends of the fingers, not when they turn to 
them. 
« The advantages of this instrument are, 
a X 
897 
that its tones are incomparably sweet beyond 
those of any other; that they may be swelled 
and softened at pleasure by stronger or weaker 
pressures of the finger, and continued to any . 
length; and (hat the instrument being once 
welt tuned, never again wants tuning.” 
“ Analogous to these sounds,” says a writer 
in the Annual Register, "are those'produced 
by bells : in those last, besides the tones 
produced by their elliptical vibrations, there 
are a set of tones which may be brought by 
gently rubbing their . edges, and in which the 
whole instrument does not appear to vibrato 
in all its parts as before. 
“ Take, for instance, a bell finely polished 
at the edges; or, what will perhaps be more 
convenient, a drinking-glass: let the edges be 
as free from any tiling oiiv as possible; then, 
by moistening' the finger in water (l have 
found alum-wafer to lie best), and rubbing it 
circularly round the edge of (he glass, you 
will at length bringout the tone referred to. 
“ This note is possessed of infinite sweet- 
ness; it has all the excellences of the tone of 
a bell, without its defects. It is loud, has a 
sufficient body, is capable of being swelled 
and continued at pleasure; and besides, has 
naturally that vibratory softening which mu- 
sicians endeavour to imitate by mixing with 
the note to be played a quarter-tone from be- 
low. 
“ To vary these tones, nothing more is re- 
quired than to procure several bells or glasses 
of different tones, tuned as nearly as possible, 
which may be done by thinning the edges of 
either: or, for immediate satisfaction, the 
glasses may be tuned by pouring in water; 
tire more water is poured in, the graver the 
tone will be. 
“ Let us suppose then a double octave of 
those glasses, thus tuned, to be procured. 
Any common tune may be executed by the* 
fingers rubbing upon each glass successively ; 
and this 1 have frequently done without the 
least difficulty, only choosing those tunes 
which are slow and easy. Here then are 
numbers of delicate tones, with which musi- 
cians have been till very lately unacquainted; 
and the only defect is, that they cannot be 
made to follow each other with that celerity 
and ease which is requisite for melody. In 
order to remedy this, I took a large drinking- 
glass, and by means of a wheel and gut, as in 
the electrical machine, made it to turn upon 
its axis with a moderately quick but equable 
motion; then moistening the finger as before, 
nothing more was required than merely to 
touch the glass at the edge, without any other 
motion, in order to bring out the tone. 
“ Instead of one glass only turning in tins 
manner, if the whole number of glasses were 
so fixed as to keep continually turning by 
means of a wheel, it follows, that upon every 
touch of the finger a note would be express- 
ed; and thus, by touching several glasses at 
once, a harmony of notes might be pro- 
duced, as in a harpsichord. 
“ As I write rather to excite than satisfy 
the curious, I shall not pretend to direct the 
various ways this number of glasses may be 
contrived to turn; it may be sufficient to 
say, that if the glasses are placed in the seg- 
ment of a circle, and then a strap, as in a cut- 
ler’s wheel, is supposed to go round them 
all, the whole number will by this meana- he 
made to turn by a wheel. 
