a

‘at

TRANSACTIONS

OF THE

ROYAL SOCIETY OF EDINBURGH:
Vou. VIII.

NUN

(i

Wil

EDINBURGH,
PRINTED FOR ARCHIBALD CONSTABLE & CO. AND FRANCIS PILLANS ;
AND FOR
CADELL AND DAVIES, STRAND, AND JOHN MURRAY, ALBEMARLE STREET,
LONDON.

1818.

CONTENTS
OF

VOLUME EIGHTH.

(Parr First.)

On the Action of Transparent Bodies upon the differently
coloured Rays of Light. By David Brewster, LL.D.
F. B.S. Lond. & Edin. and F. A. 8. Ed. Page 1
. Description of a New Darkening Glass for Solar Ob-
servations, which has also the property of polari-
sing the whole of the transmitted Light... By-
David Brewster, LL. D. F. B.S. Lond: & Ed.
and F. A. S. Ed. - - 25
. Observations on the Fire-Damp of Coal Mines ; with a
Plan-for Lighting Mines, so as to guard against
its Explosion. By John Murray, M. D. F.R.S.
Edin. Fellow of the Royal College of Physicians
of Edinburgh, - - 31
. On the Lines that divide each heinsttnredad Are into Six
equal- Parts. By W. A. Cadell, ie F. B.S.
Lond. & Edin. - 61.
. On the Origin of Cremations or the Riioniites of the:
Dead. By the Rev. John. Jamieson, D. D.
F. RB. S. Edin. & F. A. S. E. = 83
. Additional Communications respecting the Blind and
Deaf Boy, James Mitchell. By John Gordon,
M. D. F. B.S. Edin. - - 129

\VIL.

vi CONTENTS.

VII. On the Education of James Mitchell, the young Man
born Blind and Deaf. By Henry Dewar, M. D.
F. R. 8S. Edin. - Page

VIII. On the Optical Properties of Mur iate of Soda, Fluate
of Lime, and the Diamond, as exhibited in their
action upon Polarised Light. By David Brewster,
LL. D: & F-R.S. Tan & Edin. and F. A. S.
Edin. - -

1X. On a New Optical and Mineralogical Piety of
Calcareous Spar. By David ic watzr, LL. D.
F. R. S. Lond. & Edin. and F. A. 8. Edin.

X. On the Ancient Geography of Central and Eastern
Asia, with Illustrations derived from Recent Dis-
coveries in the North of India. By Hugh Mur-
ray, Esq. F. R. 8. Edin. - =

XI. An Analysis of Sea-Water ; with Observations on the
Analysis of Salt-Brines. By John Murray, M. D.
F. R. 8. Edin. = 4

XII. Elementary Demonstration of the Composition of Pres-
sures. By Thomas Jackson, LL. D. F. B.S.
Edin. and Professor of Natural Philosophy in the
University of St. Andrew’s, - o
XIII. Account of the remarkable Case of Margaret Lyall,
who continued in a State of Sleep nearly Six
Weeks. By the Rev. James Brewster, Minister
of Craig. Communicated by Dr Brewster,
XIV. A General Formula for the Analysis of Mineral Wa-
ters. By John Murray, M.D. F. B.S. Edin.

137

157

165

171

205

245

249

259

{Part

CONTENTS. vil

(Part SEconp.)

XV. On the Effects of Compression and Dilatation in al-
tering the Polarising Structure of Doubly Re-
fracting Crystals. By David Brewster, LL. D.

F. RB. S. Lond. & Edin. - - Page 281

XVI. Experiments on Muriatic Acid Gas, with Observations
on its Chemical Constitution, and on some other
Subjects of Chemical Theory. By John Murray,

M. D. F. R. S. Edin. - - 287

XVIL Experiments on the Relation between Muriatic Acid
and Chlorine; to which is subjoined the Descrip-
tion of a New Instrument, for the Analysis of
Gases by Explosion. By Andrew Ure, M. D.
Professor of the Andersonian Institution, and
Member of the Geological Society, . 329

XVUL On the Laws which regulate the Distribution of the
Polarising Force in Plates, Tubes, and Cylinders
of Glass, that have received the Polarising Siruc-
ture. By David Brewster, LL. D. F. R. S. Lond.
and Edin. - - 353

XIX. Remarks, illustrative of the. Scope and Influence of
the Philosophical Writings of Lord Bacon. By
Macvey Napier, Esq. F.R.S. Lond.;& Edin.

vnd F.A.S. Edin. - 3 373
XX. Sketch of the Geology of the Environs of Nice. By
Thomas Allan, Esq. F. R. S. Edin. S = Aly

XXI. On certain Impressions of Cold transmitted from the
Higher Atmosphere, with the Description of an
Instrument adapted to measure them. By John
Leslie, F. R. S. Edin. and Professor of Mathema-
tics in the University of Edinburgh. - - 465

XX.

vili CONTENTS.

XXII. A Method of determining the Time with Accuracy,
from a Series of Altitudes of the Sun, taken on
the same side of the Meridian. By Major-Gene-
ral Sir Thomas Brisbane, Knt. F. R.S. Ed. Page 497
XXIII. Observations on the Junction of the Fresh Water of
Rivers with the Salt Water of the Sea. By the
Reverend John Fleming, D. D. F.R.S. Edin. 507
XXIV. Memoir of the Life and Writings of the Honour-
able Alexander Fraser Tytler, Lord Woodhouselee.
By the Rev. Archibald Alison, LL. B. F. BR. 8.
Lond. & Edin. - - - 515

Appenpix, containing Lists of the Members elected since
1815, z 2 565

DIRECTIONS ro rue Binver.

Plate I. To face page 58.

aan \ To follow p. $1.
—— IV. To follow p. 164.
ra i Maps of India, to follow p. 203.
— VII. To face p. 356.
—— VIII. Map, to face p. 452.

is To foll
Xx. \ o follow p. 464.

—— XI. To face p.476.

I. On the Action of Transparent Bodies upon the differently
coloured Rays of Light. By Daviv Brewster, LL. D.
F. B.S. Lonv. & Epy. & F. A. S. Ep.

(Read 5th June 1815.)

‘ROM the intimate connexion of the present subject with

the improvement of the Achromatic Telescope, it must
be admitted to be one of the most important in Optics ; while,
from the minuteness of the effects which are to be observed
and compared, it is unquestionably one of the most difficult.
From this cause very little progress has been made in the in-
vestigation. The irrationality of the coloured spaces, in pris-
matic spectra, formed by different substances, has not even
been mentioned in any of our elementary treatises on Natural
Philosophy, and there are some philosophers who have scru-
pled to receive it as a truth established in Physics.

In order to render this subject sufficiently intelligible, let us
suppose that a ray of light is transmitted successively through
two prisms, one of rock-crystal, and the other of flint-glass, ha-
ving the same refracting angles. The rock-crystal will be
found to bend the ray of light more from its primitive direc-
tion than the prism of flint-glass. The former is therefore said

_ Vox. VIII. P. I. A to

2 ON THE ACTION. OF TRANSPARENT BODIES:

to have a greater refractive power than the latter. If we again
take other two prisms of the same substances, having such re-.
fracting angles, that a ray of light is equally refracted by both,
and if we examine the spectrum which each of’ them affords,
by admitting the sun’s light into a dark chamber, it will be
found that the spectrum formed by the flint-glass is much
longer than the spectrum formed by the rock-crystal. The
flint-glass is therefore said to. have a greater dispersive power
than the rock-crystal, or a greater power of separating the ex-
treme rays from the mean ray of the spectrum. If we then
take other two prisms with their refracting angles of such a
magnitude that they produce spectra of said lengths, it will
be found by a particular mode of examination, that the colour-
ed spaces have not the same size in the two spectra. The red
and green rays will occupy more space, and the blue and vio-
let ones less space, in the spectrum formed by the rock-crystal,
than in the spectrum formed by the flint-glass. This want of
proportionality, or irrationality in the coloured spaces of differ-
ent spectra, is not of such a magnitude as to be visible upon a
mere examination of the spectra themselves. In order to ob-
serve it, we must make the prism of flint-glass refract in op-
position to the prism of rock-crystal; and if we look at the
bars of a window through the combined prisms, we shall per-
ceive on the side of the bar to which the vertex of the flint-
glass prism is directed, a fringe of green light, and on the
other side of the bar, a purple or wine-coloured fringe. The
flint-glass, therefore, acts less powerfully upon the green rays
than the rock-crystal, or they are less separated from the red
extremity of the spectrum. These uncorrected colours, have
been called the secondary spectrum, and form the principal ob-

stacle to the perfection of the achromatic telescope.
In,

UPON: THE DIFFERENTLY COLOURED RAYS OF LIGHT. 3

. In order to observe the secondary spectrum with distinctness,
a prism of sulphuric or phosphoric acid should be made to act
in opposition to a prism of flint-glass, or what is still better,
to a prism of oil of cassia; the uncorrected fringes will in this
case be remarkably broad and distinct, and I have seen them,
when a prism of flint-glass acted in opposition to a prism of
phosphoric acid, with a refracting angle of only 11°. When
we look at the bars of a window through a prism of phospho-
ric acid, they are fringed with the prismatic colours, and so dif-
ferent are these colours, in their general appearance, from the
colours formed by a flint-glass prism, that any person unac-
quainted with the subject, would immediately perceive that
there was an excess in the space occupied by the orange-co-
loured light in the spectrum formed by the phosphoric acid.
This simple experiment, may be considered as affording ocular
evidence of the irrationality of the coloured spaces.

In my Treatise on New Philosophical Instruments, I have
already published the first experiments which I made upon
this subject, and I have there pointed out a method of ob-
taining a numerical value of the magnitude of the second-
ary spectrum*. Since these experiments were published, I
have pursued the subject to a much greater length, and have
examined almost every transparent body of importance. The
results of both these sets of experiments are contained in the
following pages, and are arranged in an alphabetical order, to
facilitate the reference from the General Table given at the end
of the Paper.

* The reader is referred to this work, p.353—401. for farther details illus:
trative of this subject.

A@2 1. Acetate

4 ON THE ACTION OF TRANSPARENT BODIES:

1. Acetate of Lead, melied.

A prism of acetate of lead acting in opposition to a prism of
crown-glass, produces a onademile secondary spectrum, in
which the green fringe is on the same side of the window bar
as the vertex of the ere of acetate of lead. This last has
therefore a less powerful action on the green ee than crown-
glass.

_ A prism of acetate of lead acting in opposition to flint-glass,
produces a less secondary spectrum, but the green fringe is
still on the same side of the bar.

Owing to the imperfection of the image, I was not able to
compare this substance with bodies of a higher dispersive
power, as the secondary spectrum became too small.

2. Acid, Acetic.

The acetic acid acts more powerfully upon the green rays
than flint-glass.

It acts a little more powerfully upon the green rays than
crown-glass.

It acts less powerfully upon the green rays than rock-cry-+
stal.

It acts a little less powerfully upon the green rays than mu-
riatic acid ; but it is very difficult, in this case, to perceive the
secondary spectrum.

3. Acid, Citric.
Citric Acid acts more powerfully upon green light than flini-
glass.
4. Acid, Malic.

Malic Acid acts more powerfully upon the green rays than
flint-glass.
It

UPON THE DIFFERENTLY COLOURED RAYS OF LIGHT. 5

It acts less powerfully upon the green rays than crown-
glass.

5. Acid, Muriatic.

Muriatic Acid acts much more ee upon green light
that flint-glass.

It acts more powerfully upon. green light than crown-glass.

It acts less powerfully upon green light than rock-crystal.

It acts less powerfully upon green light than water.

It acts very much less powerfully upon green light than sul-
phuric acid.

6. Acid, Nitric.

Nitric acid acts much more powerfully upon the green rays
than flint-glass.

It acts a little more powerfully upon the green rays than
crown-glass.

It acts much less powerfully upon. the green rays than sul-
- phuric acid.

7. Acid, Nitrous.

Nitrous acid acts much.more powerfully upon green light
than flint-glass.

It acts less powerfully upon green light than topaz. (Nota.
good observation.)

It acts less powerfully upon green ight than rock-crystal.

It acts less powerfully upon green light than nitric acid.

It has nearly the same action upon green light as crown-
glass; an uncorrected green fringe appearing towards the
vertex of the nitrous acid prism, when it is inclined to the in-
‘cident ray, and, towards the vertex of the crown-glass prism,
when it is placed first, and-inclined to the incident ray. The
fringe is, however, greater in the latter case, and therefore the

acid

6 ON THE ACTION OF TRANSPARENT BODIES

acid may be regarded as exercising a greater action upon the
green rays than the glass.

When the nitrous acid acts in opposition to the muriatic acid,
no uncorrected colour is perceived.

8. Acid, Phosphoric.

Phosphoric Acid acts very much more powerfully upon green
light than flint-glass. The secondary spectrum is very vivid
and beautiful.

It acts much more powerfully upon green light than crown-
glass. The secondary spectrum is very distinct.

It acts much more powerfully upon green light than the mu-
riatic acid.

Its action upon green light is nearly as small as that of su/-
phuric acid. By inclining the phosphoric acid prism, the uncor-
rected green light appears towards its vertex ; but by inclining
the sulphuric acid prism, it does not appear. Hence the phos-
phoric acid acts a little more powerfully upon green light than
the sulphuric acid.

9. Acid, Phosphorous.

Phosphorous Acid acts more powerfully upon green light
than flint-glass, crown-glass, rock-crystal, or water.

10. Acid, Prussic.

Prussic Acid acts much more powerfully upon the green rays
than flint-glass.
It acts more powerfully upon the green rays than crown-
glass.
When it acts in opposition to blue topaz, no uncorrected co-
Jour is visible. The refracting angle, however of the topaz
prism,

UPON THE DIFFERENTLY COLOURED RAYS OF LIGHT. Ti

prism, was too small for ascertaining accurately the relative ac-
tion of the two bodies.
It acts less powerfully upon the green rays than water.
When it. acts in opposition to muriatic acid, no-secondary
spectrum is perceived.

11. Acid, Sulphuric.

Sulphuric Acid acts more powerfully upon the green. rays-
than flint-glass, and affords a secondary spectrum greater than:
any other substance.

It acts. more powerfully upon the green light than crown--
glass, muriatic acid, rock-crysta!, fluor-spar, water, and phospho-
ric acid.

12. Acid, Sulphurous,—water saturated with the gas.
Sulphurous Acid acts more powerfully upon green light than:
Alint-glass, crown-glass, rock-crystal, and water.

| 13. Alcohol.
Alcohol acts less powerfully upon the green rays than muria-
tic acid and water.

It acts rather more powerfully upon the green rays than
flint and crown glass.

. When it acts in opposition to ether, no uncorrected colour
is seen.

14. Almonds, Oil of.

Oil of Almonds acts more powerfully upon green light than
Jlini-glass..

It acts a little less powerfully upon green light than crown-.
glass.
S

15... Almonds,

8 ON THE ACTION OF TRANSPARENT BODIES

15. Almonds, Bitter, Essential Oil of *.
This oil acts more powerfully upon green light than oi/ of
cassia, sulphur, and balsam of Tolu.
It acts less powerfully upon green light than oil of anise-
seeds, flint-glass, and crown-glass.

16. Amber.
Amber acts less powerfully upon green light than crown-glass
and rock-crystal.
It acts a little less powerfully upon green light than flint-

glass.
It acts less powerfully upon green light than rock-salt.

17. Amber, Oil of:

This oil acts less powerfully upon green light than orange-
coloured glass, oil of lavender, flint and crown glass, topaz, and
gum-arabic.

It acts very much more powerfully upon green light than
oil of cassia.

It acts more powerfully upon green light than oil of anise-
seeds.

18. Ambergris, Oil of:

This oil acts less powerfully upon green light than topaz,
rock-crystal, alcohol, and water.

It acts more powerfully upon green light than oil of cum-
min.

19. Anise Seeds, Oil of.

This oil acts less powerfully upon green light than oil of sas-

safras, oil of amber, and orange-coloured glass.

It

* IT am indebted for this oil to my friend Dr Gornoy. It is a part of that
which Mr Bnonis used in his interesting experiments on the action of Vegetable
Poisons,

‘UPON: THE DIFFERENTLY COLOURED RAYS OF LIGHT. ‘9

It acts more powerfully upon green light than oil of cas-
sid.

20. Arabic, Gum.

Gum Arabic acts more powerfully upon green light than oi
of cassia, balsam of Tolu, and flint-glass.

When it opposes crown-glass, the uncorrected colour is
scarcely perceptible ; the excess of action on green light being
on the side of the gum.

It acts less powerfully upon green light than ¢opaz and rock-
crystal. :

21. Beech Nut, Oil of.

This oil acts less powerfully on green light than crown-
glass.
_ It acts a very little less powerfully upon green light than
Slnt-glass.

22. Bergamot, Oil of.
This oil acts less powerfully upon green light than flint and
crown glass.
No uncorrected colour is visible when it acts in opposition
to oil of marjoram.
23. Beryl.
Beryl acts more powerfully upon green light than Jlint and
crown glass.
24. Borax.

Borax acts more powerfully upon green light than flint and
trown glass.

Vou. VIL PL B ‘25. ies

10 ON THE ACTION OF TRANSPARENT BODIES.

25. Glass of Borax.

Glass of Borax acts more powerfully upon green light than
flint and crown-glass.

26. Calcareous Spar.

Calcareous Spar acts. less powerfully upon green light than.
topaz and rock-crystal.

It acts more powerfully upon green light than flint-glass.

When opposed to crown-glass, 1 have not been able to per-
ceive distinctly any uncorrected colours.

27. Canada Balsam.

Canada Balsam acts less powerfully upon green light than
flint and crown glass.
It acts more powerfully upon green light than oil of cloves.

28. Capivi, Balsam of.
This balsam acts less powerfully upon green. light than
crown-glass.
It acts more powerfully upon green light than oil of marjo-
ram.
When it disperses in opposition to flint-glass, no secondary
spectrum is visible.

29. Caraway-Seeds, Oil of.
This oil acts less: powerfully upon green light than crown
and flint glass.
30. Carbonate of Lead.

This metallic salt acts more powerfully upon the green rays.
than oil of cassia.
It

UPON THE DIFFERENTLY COLOURED RAYS OF LIGHT. li

It acts very little more powerfully than the balsam of
Tolu.

31. Cassia, Oil of:

Oil of Cassia acts less powerfully upon green light than sul-
phur, balsam of Tolu, and every other substance with which I
have compared it. With sulphur the uncorrected colour is just
visible.

When acting in opposition to sulphuric acid, it forms a se-
condary spectrum of a very large size; these substances being
at the opposite extremities of the scale.

32. Castor Oil.
Castor Oil acts less powerfully upon green light than crown-
glass. :

It acts a very little less powerfully upon green light than
Juni-glass.

33. Chamomile, Oil of.

This oil acts less powerfully upon green light than crown-
glass.

It acts a little less powerfully upon green light than flint-
glass.

34. Cloves, Oil of.

Oil of Cloves acts less powerfully upon the green rays than
oil of lavender, Canada balsam, and flint-glass.

_It acts more powerfully upon the green rays than oid of sas-
safras, and oil of cummin.

B2 35. Copal,

12 ON THE ACTION OF TRANSPARENT BODIES

35. Copal, Gum.

Gum Copal acts less powerfully upon green light than crown-
glass.

It acts a very little less powerfully on green light than flint-
glass,

36. Cummin, Oil of.

This oil acts less powerfully upon green light than o7/ of la-
vender, flint-glass, and crown-glass.

It acts more powerfully upon green light than balsam of:
Tolu.

37. Diamond..

When diamond acts in opposition to oil of cassia, the uncor-
rected colours are nearly of the same magnitude, and in the
same situation, as when the oil of cassia is combined with flint,
glass. Hence diamond has nearly the same action upon green
light as flint-glass,

38. Dill Seed, Oil of.

This oil acts less powerfully upon green light than crown~
glass.

It acts a very little less powerfully upon green light than-
flint-glass.

39. Ege, White of an.

The white of an.egg acts more powerfully upon green. light:
than crown-glass, topaz, muriatic. acid, nitric acid, and fluor
spar.

It acts less powerfully upon green light than water, and
much less than sulphuric acid.

40. Ethers.

UPON -THE DIFFERENTLY COLOURED RAYS OF. LIGHT. 13

40. Ether.

Ether seems to have the same action upon green light as ai-
cohol.

41. Fennel-seeds, Sweet, Oil of.

This oil acts much less powerfully upon green light than
junt and crown. glass, and.less powerfully than oi! of dill
seed.

42, Fenugreek, Oil of.

This oil acts less powerfully upon green light than flin¢ and -
crawn glass.

43. Fluor-Spar.

Fluor-Spar acts less powerfully upon green light than sulphu-
ric acid, and the white of an egg.

44. Glass, Crown.

Crown-glass acts more-powerfully upon green light than
fint-glass, oil of spermaceti, oil of olives, oil of ambergris, copal,
or oil of juniper.

It acts less powerfully upon green light than gum Arabic, al-
cohol, topaz, fluor-spar, the acids, rock-crystal, and water. .

45. Glass, Flint.

Flint-glass acts less powerfully upow green light than oil of
spermaceti, oil of olives, oil of ambergris, essential a of juniper,
oil of rape-seeds crown-glass, &c.

It acts more powerfully upon green light than Canada bal-
sam, and almost all the essential oils, excepting those ey
mentioned,

When. .

14 ON THE ACTION OF TRANSPARENT BODIES

When flint-glass acts in opposition to balsam of Capivi, nut
oil, oil of rhodium, and oil of rosemary, no secondary spectrum is
~visible.

46. Glass, Opal-coloured.

This glass acts more powerfully upon green light than oil of
cassia, and balsam of Tolu.
It acts less powerfully upon green light than flint-glass.

47. Giass, Orange-coloured.

This glass acts less powerfully upon green light than crown-
glass, and very little less than flint-glass.

It acts more powerfully upon green light than oil of amber,
and oil of anise-seeds.

48. Glass, Red-coloured.
This glass acts less powerfully upon green light than flint
nd crown glass.
49. Hyssop, Oil of.

This oil acts less powerfully upon green light than crown-
glass, and a little less powerfully than flint-glass, and oil of pep-
permint.

50. Ice.

When ice is opposed to flint-glass, it forms a secondary spec-
trum, having the same position, and nearly the same magni-
tude, as when water is combined with flint-glass.

51. Juniper, Gum.

This gum acts less powerfully upon green light than crown-
glass.
52. Juniper,

UPON THE DIFFERENTLY COLOURED RAYS OF LIGHT.. is

52. Juniper, Oil of:
This oil acts less powerfully upon green light than crown-
glass.
It acts a very little more powerfully upon green light than .
Jfint-glass.

53. Lavender, Oil of:

This oil acts less powerfully upon green light than flint and
crown glass.

It acts more powerfully upon green light than oil of cassia,
balsam of Tolu, and oil of amber..

54. Lemon, Oil of.

This oil acts less powerfully upon green light than crown-
glass, and a very little less powerfully than flint-glass:

55. Leucite. -

This mineral acts more powerfully upon green light than
fiint and crown glass.
It acts less powerfully upon green light than topaz.

56. Marjoram, Oil of:

This-oil acts less powerfully upon green light than flint and -
crown glass, and. nut oil.

57. Muriate of Antimony.

This fluid, (the dispersive power of that which I used was.
0.059,) acts far less powerfully upon green light than flint and —
crown glass.

It acts more powerfully upon green light than oil of sassa-. -

fras.

6 ON THE ACTION OF TRANSPARENT BODIES

It exercises almost the same (perhaps a litile greater) action
“upon green light, as oil of cloves.
58. Nitrate of Potash.

The refractive force which produces the greatest refraction
in this salt, acts much less powerfully upon green light than -
crown-glass, and a little less powerfully than flint-glass.

59. Nut Oil.
Nut oil acts less powerfully upon green light than crown-
glass.
When it acts in opposition to flint-glass, no secondary spec-
trum is visible.
It acts more powerfully upon green light than oil of marjo-
ram.
60. Nutmegs, Oil of.
This oil acts less powerfully upon green light than crown-
glass, and a very little less than ane Saat.
61. Olives, Oil of.
Oil of olives acts less powerfully upon the green rays than
crown-glass, and a very little less than flint-glass.
62. Pennyroyal, Oil of:
This oil acts much less powerfully upon green light than
crown-glass, and considerably less than flint-glass.
63. Peppermint, Oil of.

Oil of peppermint acts less powerfully upon the green rays
than crown-glass, and a little less powerfully than flint-glass.

64. Poppy,

UPON THE DIFFERENTLY COLOURED RAYS OF LIGHT. [7

; 64. Poppy, Oil of.
This oil acts less powerfully upon green light than either
flint or crown glass.

65. Rape-seed, Oil of.

This oil acts less powerfully upon the green rays than crown-
glass, and a very little more powerfully than flint-glass.

66. Rhodium, Oil of.

This oil acts less powerfully upon green light than crown-
-glass, and more powerfully than oil of cloves.

When a prism of oil of rhodium witha great refracting angle,
‘was opposed to a prism of flint-glass with a small angle, the
green fringe appeared towards the vertex of the flint-glass
prism.

When a prism of oil of rhodium with a small refracting
angle, was made to correct a prism of flint-glass with a large
angle, the uncorrected green appeared towards the vertex of
the oil of rhodium. Hence we may infer that these two bo-
dies exercise the same action upon the green rays.

67. Rock-Salt.

This substance exercises a much greater action upon green
light than rosin.

It exercises a less action upon the green rays than crown-
glass. Its action exceeds a little that of Jlint-glass, and is a
little less than that of calcareous spar. —

rarity wy 68. Rock-Crystal.

This intents acts more powerfully upon green Awe than
_Jlint-glass, crown-glass, and muriatic acid.

Vor. VIII. P. I. Cc It

18 ON THE ACTION OF TRANSPARENT BODIES

It acts less powerfully upon green light than sulphuric acid,
phosphoric acid and water.

69. Rosemary, Oil of.

This oil acts less powerfully upon green light than crown-.
glass, and a very little more powerfully than flint-glass.

70. Rosin.

This substance acts less powerfully upon green light than:
crown-glass and flint-glass. The secondary spectrum with.
flint-glass, is fully as great as that produced by flint-glass.oppo-
sed to crown-glass.

Rosin acts a little less powerfully upon the green rays than
oil of cloves.

. 71. Rue, Oil of

This oil acts more powerfully upon the green rays than

crown-glass, and a very little more powerfully than flint-glass..

72. Sage, Oil of:

This oil acts less powerfully upon green light than either
crown or flint glass.

73. Sassafras, Oil of:

This oil acts more powerfully upon green light than o#/ of:
cassia, balsam of Tolu, and oil of anise-seeds, but less powerful-
ly than crown and flint glass, and oil of cloves.

74. Savine, Oil of.
This oil acts less powerfully upon the green rays than crown-.
glass, and perhaps a little less powerfully than flint-glass ; but

more powerfully than oi/ of spearmint, ie
75. Selenite.

WPON THE DIFFERENTLY COLOURED RAYS OF LIGHT. 19

15. Selenite.
This mineral acts more powerfully upon green light than
crown and flint glass, but less powerfully than ¢opaz.
76. Spearmint, Oil of.
This oil acts less powerfully upon green light than flint and
crown glass, and oil of savine. -
77. Spermaceti, Oil of:
This oil acts more powerfully upon the green rays than flint-
glass and oil of marjoram, and less powerfully than crown-glass.
78. Sulphur.

Sulphur produces a secondary spectrum when opposed to
Jflint-glass and crown-glass, nearly as great as when oil of cassia
is opposed to them. When it refracts in opposition to oil of
. Cassia, no uncorrected colour is visible, but the oil appears
to have a less action upon the green rays.

79. Sulphuret of Carbon.

This fluid acts much less powerfully upon the green rays
than flint and crown glass, and all the essential oils except oil
of cassia.

Its action does not greatly exceed that of the oid of cassia.

80. Super-sulphuretted Hydrogen.

. This fluid has a more powerful action upon the green rays
than flint and crown glass. When it refracts in Opposition to
water, no uncorrected colour is visible,

C2 81. Tartrate

20° ON THE ACTION OF TRANSPARENT BODIES

81. Tartrate of Potash and Soda.

This salt acts more powerfully upon green light than flint-
glass, and does not appear to act very differently from crown-

glass.
82. Thyme, Oil of.

This oil acts. less powerfully upon green light. than flint’
and crown glass, and oil of juniper, but more powerfully than:
oil of cloves.

83. Tolu, Balsam of.

This balsam acts less powerfully upon the green rays than:
oil of anise-seeds, oil of sassafras, and oil of lavender, and fint-
glass, but more powerfully than oil of cassia and sulphuret of

carbon.
84. Topaz, Blue.

This mineral acts more powerfully upon green light than:
crown and flint glass, selenite, and Jeucite, but less powerfully
than water and rock-erystal.

85. Tourmaline.

This mineral acts more powerfully upon green light than:
crown and flint glass.

86. Turpentine, Oil of:

This oil acts more powerfully upon the green rays than oil
of sassafras, oil of cloves, and Canada balsam, but less power-
fully than crown and flint glass. ;

87. Water:

UPON THE DIFFERENTLY COLOURED RAYS OF LIGHT. QF

87. Water.

Water acts more powerfully upon the green rays thar flint
and crown glass, rock-crystal, the white of an egg, and the great-.
er number of the acids. It acts less powerfully, however, than
the phosphorous, sulphurous, phosphoric and sulphuric acids.

88. Wormwood, Oil of.

This oil exceeds flint and crown glass in its action upon gree
light, but is inferior to oil of sassafras and oil of cloves.

89. Zircon:

This mineral acts less powerfully upon green light than
crown-glass, but no secondary spectrum was visible when it re-
fracted in opposition to flint-glass.

In order to present under a general view the results of the:
preceding experiments, I have arranged the various substances
in a Table, inversely according to their action upon green:
light ; that is, the bodies at the top of the Table form spectra:
in which the red and green spaces are most contracted, and the:
blue and violet ones most expanded. The relative position of
several of the substances, particularly the essential oils, is quite
empirical ; but it can readily be found by a reference to the
preceding experiments, whether or not the relative action of
any two bodies has been actually determined.. To have
attempted to fix the exact place of every substance, would have
required a great degree’ of labour, and more time than I could
easily command; and it is almost certain, that the Table
would still have been incomplete, as there are many of the
essential oils, and some minerals, which do not exhibit
any difference in their action upon green light. Several
of the oils, too, which I used, had been exhausted by re-

peated.

22 ON THE ACTION OF TRANSPARENT BODIES

peated trials, and as it would have been impossible to replace
them from the same source, the prosecution of the experi-
ments with fresh oils, sold under the same name, might have
introduced a new degree of uncertainty among the results.

For all the purposes of the Practical Optician, the relative
position of the substances, where it has been determined by
experiment, is sufficiently accurate. Numerous combinations
for correcting the secondary spectrum, may be formed, ei-
ther by taking two media that have nearly the same ac-
tion upon green light, while they differ in their powers
of refraction and dispersion, or by adopting the ingenious
method discovered by Dr Brarr, and fully described in the
Transactions of this Society. In the production of perfect
achromatic instruments, the optician cannot expect much more
aid from the principles of optics. The great, and almost the
only desideratum, is to obtain two kinds of glass, which shall
have the same action upon green light, while they differ suffi-
ciently in refractive and dispersive power; and it is chiefly
from the labours of the Chemist, guided by the preceding in-
quiries, that such a discovery can be expected.

There is still, however, another source of error, of which
neither the Theoretical nor the Practical Optician has hitherto
been aware. It arises from a crystallisation in the glass, which
is always accompanied with double refraction, and with a va-
riation of density. This crystallisation, which most frequent-
ly affects the flint-glass, and which can easily be detected by its
action upon polarised light, should be carefully removed from
every piece of glass used in the construction of optical instru-
ments, by annealing it in an oven of a high temperature,
where the heat is regularly and very slowly reduced. The ex-
periments upon which this opinion is founded, will form the
subject of another paper.

TABLE

UPON THE DIFFERENTLY COLOURED RAYS OF LIGHT. 23

TABLE of Transparent Bodies, arranged inversely according
to their Action upon Green Light.

1 Om or Cassa.
Sulphur.
Sulphuret of carbon.
Balsam of Tolu. °
& Carbonate of lead.
Essential oil of bitter almonds.
Oil of anise-seeds.
Oil of cummin.
Oil of sassafras,
10 Oil of amber.
Acetate of lead melted.
Opal-coloured glass.
Orange. coloured glass.
Red-coloured glass.
15 Oil of sweet fennel seeds:
Oil of cloves.
Muriate of antimony.
Oil of lavender.
Canada balsam.
20 Oil of turpentine.
Oil of sage.
Oil of pennyroyal.
Oil of poppy.
Oil of hyssop.
25 Oil of spearmint.
Amber.
Oil of lemon.
Oil of caraway-seeds.
Oil of nutmegs..
30 Oil of thyme.
Oil of peppermint: .
Oil of bergamot.
_ Oil of marjoram.
Oil of wormwood.
35 Oil of dill-seeds.
Oil of chamomile. .
Castor-oil.
Gum copal.
- Rosin.
40 Diamond.
Nitrate of potash«
Oil of beech-nut.
Oil of rue.
Oil of savine.
45 Nut oil.

Balsam of capivi.
Oil of fenugreek.
Oil of rosemary.
Oil of rhodium.

50 Fuint Guass.
Zircon.

Oil of olives.
Oil of rape-seed.
Oil of spermaceti,

55 Oil of juniper.
Oil of ambergris.
Calcareous spar.
Rock-salt.

Gum juniper.

60 Tartrate of potash and soda.
Oil of almonds,
Crown-Guass.
Gum-Arabic.
Alcohol.

65 Ether.

Borax, glass of.
Borax.
Tourmaline.
Leucite.

70 Selenite...
Beryl, .

Topaz, blue.
Fluor-spar.
Citric acid. .

75 Malic acid.
Acetic acid.
Nitrous acid.
Muriatic acid:
Prussic acid.

80 Nitric acid.
Rock. crystal.
White of an eggs
Ice.

Water.

85 Super-sulphuretted hydrogen.
Phosphorous acid.
Sulphurous acid.
Phosphoric acid.

89 Sunruuric Acip,

IL.

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5 REN Bh see

re 4):

—

IL Description of a New Darkening Glass for Solar Observa-
tions, which has also the property of polarising the whole
of the transmitted Light. By Davin Brewster, LL. D-
F. R. S. Lonp. & Enix. & F. A.S. Ev.

[Read 1st May 1815.]

T will be readily admitted by every person who has been
accustomed to solar observations, that an apparatus for di-
minishing the intensity of the sun’s light, without distorting
or colouring the resulting image, is still a desideratum in Prac-
tical Astronomy.

Dr Herscuet is the only person who has given any degree
of attention to this subject. When he applied his powerful
telescopes to examine the surface of the sun, he found that the
ordinary method of attenuating the light by smoked or colour-
ed glasses, was of no avail; and it was in the prosecution of his
experiments for determining the relative advantages of differ-
ently coloured glasses, or of combinations of differently colour-
ed glasses, that he was conducted to those splendid discoveries
respecting the invisible rays, which have formed an epoch both
in Chemistry and Optics. :

Vou VAL. Tt D The

26 DESCRIPTION OF A NEW DARKENING GLASS

The combination of coloured and smoked glasses which he
found most effectual for diminishing the heat of the sun’s rays,.
and at the same time preserving distinct vision, was extreme-
ly complicated ; and after every attempt to improve it, he
seems to have preferred another apparatus in which the light
was transmitted through a mass of diluted ink contained in a
trough bounded by plates of parallel glass. By this means he
obtained an image of the sun as white as snow, and so very
distinct, that, with a mirror nine inches in diameter, and the
eye-piece open, he could observe the sun in the meridian for
any length of time, without injuring either his eye, or the
glasses of his eye-piece.

Notwithstanding these advantages, this apparatus can never:
be brought into general use, and can only be employed in in-.
struments that are stationary. The necessity of frequently re-
newing the ink, and the difficulty of retaining it in the trough,.
are evils which are not easily remedied.

The darkening glass which we propose to substitute in place
of these contrivances, depends upon the diminution of light by
two or more reflexions within a thick plate of parallel glass.
The pencil, attenuated by reflexion, reaches the eye in the
state of white light, while the direct rays transmitted through
the plate are stopped by two pieces of metal properly disposed
upon the opposite surfaces of the parallel glass.

The nature of this contrivance will be understood from the
following figure, where AB is a section of a piece of parallel
glass, and C, D sections of two opaque plates placed on the upper
and under surfaces of this glass. A ray of light RS, incident ob-
liquely at S, will be transmitted in the direction aT, but is pre-
vented from reaching the eye by the opaque plate D. A portion
of this ray is reflected at a, and a second time at }, and emer-
ges in the direction c V in a very attenuated state. The inten-

sity

TOR SOLAR OBSERVATIONS. Q7

sity of the pencil eV may be varied either by varying the
thickness of the plate, or by R

changing the angle of inci-
dence ; and if it cannot be ren-
dered sufficiently feeble by any
of these means, it may be ex-
posed to other two reflections
at c and d, when it will emerge
in the direction e W, having its
intensity very greatly reduced.

In order that the light may be freely reflected at the points
a, 6, c and d, the opaque plates C, D must be kept at a little
distance from the surface of the glass, and all extraneous re-
flexion must be removed, by covering their interior surfaces
with a black pigment. This may be done most conveniently
by making the plates C, D rest upon the glass only by their
margins. The aperture at S, where the light is introduced,
should be of an elliptical form, so as to admit a cylindrical
pencil at an oblique incidence.

Hitherto we have supposed, the reflecting surfaces to be
sn contact with air, so that the reflecting force is allowed to
exercise its maximum action upon the incident rays. But it
is very easy to diminish the reflective power, in any ratio that
we choose, by introducing between the opaque plates and the
glass a cement either of a greater or a less refractive power
than the glass. By this means we obtain a degree of reflexion
corresponding to a refractive power equal to the quotient of
the greater refractive power divided by the lesser; and the re-
flexion will be made either from the surface of the cement,
or from the glass, according as the one or the other exercises
the most powerful action upon light.

As it may sometimes be difficult to procure a thick plate of
parallel glass, we may substitute in its place two common

D2 plates,

28 DESCRIPTION OF A NEW DARKENING GLASS

plates, cemented together by a thin layer of indurated Canada
balsam, or any other transparent substance, having the same
refractive power. The rays of light will then pass from the,
one plate into the other, without suffering either reflexion or
refraction. This compound plate may even be formed of
glasses of different colours, if we wish to produce a great de-
gree of attenuation.

The simple apparatus which has now been described, pos-
sesses a still more valuable property than that of attenuating
the incident light. The pencil ¢ V, which has undergone two
reflexions, emerges completely polarised, unless when the
angle of incidence is very small; and the polarisation continues
complete, although this angle suffers a very considerable varia-
tion. The other pencil e W is also polarised, and preserves
this character, even when the angle of. incidence has a much
wider range.

If a plate of fine flint-glass is used in the construction of the
eye-piece, we may employ it to great advantage in experiments
on polarisation, even when the light has a moderate degree
of intensity. But if the light of the sun is under examination,
the eye-piece will possess the peculiar advantage, of at the
same time attenuating and polarising the incident pencil.

The polarisation of the emergent pencils c V, e W, enables
us to explain a very perplexing anomaly in the law of the po-
larisation of light by oblique refraction *. From numerous
experiments made with piles of glass plates, I found that the
tangents of the angles at which they polarised the transmit-
ted light, were inversely as the number of plates of which the
pile was composed. ‘The coincidence of this law, with the ex-
perimental results, was extremely accurate when the number
of plates was between eight and forty-seven, corresponding to a

series

* See the Philosophical Transactions, for 18}4, p. 223.

}
‘

FOR SOLAR OBSERVATIONS. 2g

series of angles between 41° 41’ and 79° 11’.. When the light
was transmitted through one plate, it ought to have been pola-
rised, according to the preceding law, at an angle of 88° 38’;
but upon examining the image with a prism of calcareous spar,
it did not vanish in any position of the spar, even when the
incidence was greater than 88° 38’. A similar aberration from
the law takes place when the pencil is transmitted through
one, two, three, or four plates.

In order to discover the cause of this anomaly, I made a
great variety of experiments, without obtaining any satisfac-
tory result ; and it was only by examining the phenomena of
the polarising eye-piece that my attention was again called
to the subject. We have already seen, that the pencils
eV and and eW, are polarised in the plane of reflexion
Sabcde. If we now remove the lower plate D, so as to per-
- mit the direct pencil a@ T to reach the eye, the pencils c V, and.
e W will be mingled with the pencil aT. When RS is inci-
dent at an angle of 88° 38, the pencil aT ought to be com-
pletely polarised, and ought to vanish in every quadrant, when
examined with a polarising crystal. It is prevented, however,
from vanishing, by the admixture of the pencils c V and e W,
which are polarised in an opposite manner, and which will
therefore remain visible when the whole of the direct pencil
has vanished. As the angle of incidence diminishes, the in--
tensity of the pencils c V, e W suffers a very rapid diminution,
while that of the direct pencil aT receives a corresponding
augmentation. On this account, the oppositely polarised rays
eV, eW form but a very small proportion of the compound
pencil, and they are scarcely perceptible when the number of
plates exceeds eight. The union of the reflected light with the
obliquely refracted pencil, constitutes, therefore, the true cause
of the anomaly which we have been considering.

Il.

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dak gies, eae
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oe

———

TI. Observations on the Fire-Damp of Coal Mines; with a
Plan for Lighting Mines, so as to guard against its Ex-
plosion. By Joan Murray, M.D. F. BR. S. E. Fellow of
the Royal College of Physicians of Edinburgh.

[Communicated November 14. and read November 20. 1815 *.]

XPLOSIONS in mines, from the kindling of the inflam-.
mable gas, called Fire-Damp by the miners, have always
occasionally occurred. Of late they have become more fre-
quent in some of the coal-mines in this country, particularly
those in the districts of the Tyne, and the Wear, in the North
of England, and have been attended with such fatal consequen-
ces, as to have forcibly called public attention to the subject.
In an explosion in one mine, about two years ago, ninety-two
persons were killed; in another, which occurred soon after,
thirty-two lost their lives; in one which happened within
these few months, fifty-seven persons were destroyed ; and re-
eently, it has been affirmed, that several hundred lives are lost
annually

* Tt may be proper, from circumstances, to mention, that this paper is print-
ed in the text exactly as it was read. I have added at the end a few notes,
(read before the Society at a subsequent meeting), explanatory of the plan, or
eonnected with the subject.

‘32 ON THE FIRE-DAMP OF COAL-MINES,

annually from this cause. From the state of the mines, part'-
cularly in the accumulation of wastes, the collection of water,
and the increasing depth of the workings, there is reason to
fear, too, that such accidents will become more frequent. Hu-
manity loudly calls, therefore, on every effort being made to
obviate the calamity ; and even as a national concern, the im-
mense loss of property in the mines, and the probability which
has been suggested, that the working of them must ere long be
abandoned, give to the subject the highest claims to considera-
tion.

I have to submit to the Society the account of a method
which has occurred to me of lighting mines, not liable, like the
common method, to the risk of kindling the fire gas, and which
I trust may go far to obviate these unhappy occurrences. (Nete
A.)

The inflammable gas which is disengaged in coal-mines, it
is well known, is carburetted hydrogen. In some situations it
is much more abundant than in others. It has been supposed
to be produced from the decomposition of water by coal, and,
in particular, from the waste coal in the old workings, exposed
to the action of humidity. It is possible that much of it may
be from this source, and the fact, that it is most abundant in
deep mines, where such wastes accumulate, is favourable to the
opinion. This is not always, however, its origin. Much of it
is disengaged from the solid coal as it is worked, and the sur-
face of the wall of coal often continues to yield it from pores
or fissures for weeks or months. It often, too, rushes sudden-
ly, with great velocity, and in large quantities, from rents in
the incumbent strata, or from vacuities within the mass of coal,
in which it is pent up, apparently in a state of compression.
The greatness of the mass of coal confining the gas more ef-
rectually, or favouring the compression: with which it is retain-

ed,

“AND PREVENTING ITS EXPLOSION. 33

ed, may be the cause why it is more abundant in deep mines.
Still, from whatever source it may be extricated, if the fact be
correctly stated, that it has always an intermixture of carbonic
acid, it is probable that it is in all cases derived from the de-
composition of water by coal. (Note B.)

It seems ‘to be altogether impracticable to prevent the pro-
duction of this gas. To decompose or neutralise it in the mine
by any chemical agency, as has been suggested, seems to be
equally so. Only two resources apparently remain,—first to
employ means of discharging it, so as to prevent any accumu-
lation of it in large quantities ; and, secondly, to guard against
its inflammation in working the mine, when from circumstan-
‘ces occasionally unavoidable it does accumulate, until it can be
discharged.

The circumstance of explosions from the firing of this gas
not occurring in many mines, situated even in districts where,
from the nature of the coal, the depth of the workings, or
other causes, such occurrences are frequent, seems to prove
that there is no necessary accumulation of fire damp in
the mine,—that the accumulation does not so much take
place from unavoidable deficiency of ventilation, as from acci-
dental obstructions to it in particular situations, or occasional
eruptions of the gas from cavities in the coal or its accompany-
ing strata, against which scarcely any.system can effectually
guard,—that, therefore, the ventilation may be rendered effec-
tive, and, by prudent and careful management, may be con-
ducted so as to carry off the quantities evolved. In the Fell-
ing Colliery, near Newcastle, in which the explosion that de-
stroyed nearly a hundred persons, about three years ago, took
place, the mine, it is stated, was considered as a model of per-
fection in the purity of its air, from the system of ventilation ;

and in an account of a second explosion in this mine, in which
Vo. VIII. P. I. . E twenty-

34 ON THE F!RE-DAMP OF COAL-MINES,

twenty-three were killed, it is mentioned, “ that so powerful
was the stream of fresh air in all the working parts-of the mine,
that the candles could with difficulty be kept from going out,”
and * that the persons employed in it declared, that they never
wrought in a pit so. wholesome and pleasant.” In another
mine, in which, in the same year, an explosion took place, in
which thirty-two men were killed, the general arrangements.
were so perfect, that it was considered by every one acquaint-.
ed with the state of it, to be altogether free from danger.
These facts seem to shew, that there is.no want in the power
of ventilation ; and indeed it has been: stated on high practical.
authority, that in this respect no great improvement can be ex-
pected *, If these statements are correct, what is principal-
ly to be looked for, independent of employing the best method
of ventilation, and of a more strict attention to the state
of the mine, in: preventing any partial obstruction to its. ope-.
ration, is some mode of security against the inflammation of
the gas, either as it is discharged from the fissures of the-coak
in working, or when it does. accumulate-partially, from causes
frequent, though occasional, in their occurrence.

So far as can be learnt from the-circumstances of those ex-
plosions. which have occurred in the Newcastle and Sunder-
land mines, the principal causes. giving rise to the accumula-
tion of the inflammable gas, have. been some neglect with re-
gard tothe means of ventilation,—such. as failing to keep up
the fire sufficiently at the: mouth of the air shaft, or. obstruc-
tions in the passages or in the old wastes. The latter appear
to be the most common cause; parts of the roof fall in, in the
old excavations, or, by a yielding at the bottom of the pillars

and:

* Report by Mr Buppue to the Society for. preventing Accidents in Coal.
mines.

AND PREVENTING ITS EXPLOSION. 35

and walls, the sides of the passages gradually approach, form-
ing what the miners calla creep ; sometimes, too, the stoppings
and trap-doors which direct the current of air through the pas-
sages, are neglected, the ventilation is either partially stopt, or
is impeded, the fire-damp gradually accumulates, and ming-
ling with the air, forms a mixture which is capable of explo-
ding. There is reason to believe, too, that in some cases, the
accident has arisen from the sudden discharge of the gas from
fissures in the strata, or from the opening of a cavity in the
mass of coal in which it had been confined ; it often takes fire
at the candles of the miners, when discharged in this way ; is
sometimes discharged in large quantity with the greatest vio-
lence ; and if intermingled with a rapid current of atmosphe-
ric air, the inflammation may increase in rapidity to an explo-
sion.

It is obvious, that attention to these circumstances is of the
first importance ; and, so far as improvements in the system of
the mines in that respect are practicable, their propriety can-
not be questioned. As it appears, however, that there are some
causes which ‘can scarcely be effectually obviated, and as the
utmost attention which can reasonably be expected, seems, un-»
der the circumstances of the mines, and the constant genera-
tion of the enormous quantities of gas which they yield, to be
insufficient for perfect security, the importance becomes evi-
dent, of some mode of lighting being devised, which should
guard against the firing from the large discharge, or eccasional
accumulation of the inflammable air, while, at the same time,
the danger should be indicated, so that the necessary means to
remove it might be employed.

No difficult or complicated method can be expected to suc-
ceed. Any method to be successful, must be simple, easy of
execution and of use, and not too expensive. That which I

E2 have

36 ON THE FIRE-DAMP OF COAL-MINES,

have now to explain, will be found, I trust, possessed of these
advantages.

The facts on which it is in a great measure founded, are,
that the inflammable gas accumulates in the roof of the mine,
—that it is fired, in the usual mode of lighting, before the mix--
ture of it with the atmospheric air fills the-mine, or that part»
of it in which the accumulation is taking place,—and that it:
cannot fill it while the mine-is worked; as the respiration of the:
workmen would be: previously affected. The miner works:
with his candle or lamp-at a certain elevation, occasionally mo-.
ving with it; and thus when the fire-damp has accumulated so:
far as to fill a considerable part of the roof, the accidental ap-.
proach of the lamp, or some concussion throwing the gas:
downwards, so as to bring it into contact with the flame, sets:
it on.fire. In one of the explosions, for example, within these
two years, that of the Hall Pit near Sunderland, in. which thir-:
ty-two men were killed, the explosion was supposed to have.
been occasioned by the fall of a stone from the roof, which car--
vied the inflammable air with it, so as to bring it into contact:
with the pitmens’ candles; and this circumstance of a flake or
mass falling from the roof, and throwing the inflammable air:
before it to the candles, has been often assigned as-a cause of.
these explosions. It isa proof of what is indeed sufficiently
established, the accumulation of the inflammable gas in the:
roof of the mine. .

The method, therefore, which I would propose is, to bring
the supply of air to sustain the combustion of the lamp from:
the floor of the mine. This may be easily done by burning:
the lamp within a glass-case, having a small aperture at the
top to. admit of the escape of the heated air and smoke, and»
having attached to the under part of it a tube reaching to the
floor of the mine to convey the-air. Figure Ist, Plate I. re-
presents this in a fixed lamp.

One

AND PREVENTING ITS EXPLOSION- 37

One principal difficulty in contriving any safe mode of light-
ing coal-mines, must be that of having moveable lights ;. for
these the workmen will often: find it necessary, and in ge-
neral will be desirous, to employ. This may be easily attain-
ed by connecting with the bottom of the case or lantern, a
flexible tube, air-tight or nearly so, which may be done by a
tube of prepared leather varnished ; this tube being of such a
length as to reach nigh to the floor. The lamp can thus be
held in the hand, or attached to.any occasional support. Fig. 2.
represents a lamp of this. kind.

No danger, or scarcely any, I conceive, can arise in the use
of this apparatus. If the size of the upper aperture be duly
adjusted, no air cam enter by it to the lamp, for the current of
heated air will prevent this. And this air can never be:heated.
so high:as.to. kindle any mixture of carburetted hydrogen:

No inflammable air can. enter from the-hottom; so as to be-
capable of kindling, for the reason already assigned, that from.
its levity it rises to the roof:of the mine, and the mixture of it
with atmospheric air, which is explosive, is always accumulated
there. Nor can this increase so as to extend to the floor of the.
mine, and the miner remain present, as, previous to this, the:
effect of this mixed air, received by respiration, would be felt,
and give warning of the danger. (Note C.)

The flexible tubes of the moveable lamps may be easily pre-
pared, and preserved air-tight : and there being so ready a sup--
ply of air from below, if there were any minute fissure in the.
sides of the tube, no air would enter by it, or the quantity.
would be so small, and so much, diluted by intermixture, that
there could be no risk. In the fixed lamps, having an iron or
copper tube: conveying the air, there could be no risk of this
kind, and if it were necessary, similar metallic tubes, with
moveable circular joints, could be adapted to the moveable;
lamps.

There

38 ON THE FIRE-DAMP OF COAL-MINES,

There is another circumstance which will give security to
these lamps, should it ever happen, from any unforeseen cause,
that a mixture of inflammable air were introduced,—the rare-
faction of the air within the lamp, and especially near the
flame. It is well known that mixtures of inflammable air with
atmospheric air, or even with oxygen, cannot be inflamed, if
the elastic fluid be in a certain degree of rarity. The experi-
ments of Grorrnus with regard to this are important. They
prove that the combustibility, of the inflammable gases is so
much dependent on their density, that if 2 mixture of any of
them with oxygen gas be rarefied to a certain extent, either by
the air-pump, or by elevation of temperature, it could not be
kindled by the electric spark which kindled the same mixture
easily in its denser state. Hence, as he justly remarked, bo-
dies may be inflammable under pressure, the mflammability of
which is weak, or not apparent in a rarefied atmosphere ; and
in mixtures of different inflammable gases with atmospheric
air, there will be a certain degree of density within which only
the mixture can be inflamed. The inflammability of any mix-
ture of carburetted hydrogen with atmospheric air, is limited
to certain proportions, and in all of them is inconsiderable. Dr
Tuomson states what is .a proof of this, that he had never been
able to cause any mixture of it with atmospheric air to ex-
plode, it merely burnt rapidly ; ; its exploding in the mme, must
therefore probably be owing to the large mass of it inflamed,
and to the state of condensation 4 in which it exists. Another
circumstance which shews, that even in the mine, its power of
kindling so as to explode, is not more than what just renders
it possible, is, that it is not kindled by the ignited sparks from
the collision of steel and flint, a machine producing these be-
ing used to give light in working or exploring the mine, when
mauch danger is dreaded, and having very seldom caused explo-

sion.

-AND PREVENTING ITS EXPLOSION. 39"

sion. Thus coming barely within the verge of the power of
exploding, and owing it to. these circumstances of quantity and:
condensation, there is every probability, that if kindled in small
quantities it would not explode, and that, presented: to an igni-
ted body much diluted and in a rarefied state, it would not
even inflame. Hence the chance of its inflaming in a lamp
such as that described, is inconsiderable, were it even admitted.
to the flame; and the certainty of its not exploding might al-
most be depended on. The security from this might even be
carried so far, by adapting properly the size of the upper aper-
ture, so as to produce the greatest degree of rarefaction in the-
air, that if a mixture of the fire-damp with atmospheric air
were introduced, it might, instead of inflaming, become inca-
pable of supporting the combustion, or at least might so far
weaken the flame, as to give indication of the danger.

Lastly, If even, from some singular cause, an explosion did
bappen within the case-of the lamp, it appears to me very
doubtful if it would. be propagated farther. It must be ex-
tremely feeble. The flame or ignition could not be communi-
cated by the upper aperture to. the air without, partly from its
smallness, and partly from the upper part of. the lamp being
previously occupied by air not capable of kindling. Nor could
it be easily. communicated downwards through the tube, espe-
cially in a flexible tube, the sides of which would first yield,
and then collapse ; and though conveyed downwards, there
would be little or no probability of an air occupying the floor
of the- mine capable of being inflamed. The risk of such a
communication, if it were thought there-were any, might pro-..
pably also be diminished by conveying the air rather by seve-
ral small tubes. than by one larger. Other contrivances suffi-
eiently simple, if they were supposed necessary, might be em-
ployed, A cup containing water, for example, or a saline so-

lution,

40 ON THE FIRE-DAMP OF COAL-MINES,

lution, might, in situations peculiarly hazardous, be suspended
within the case, over the orifice of the air-tube, which, if any
explosion were to happen, would, by the agitation, throw out
the fluid, and extinguish the flame.

If, notwithstanding all these means of safety, there should
in any particular case be any dread of danger from the admis-
sion of inflammable air with the common air, this might
be completely obviated by an additional arrangement. The air
to supply the lamps might be brought by a cast-iron pipe from
any part of the mine where the danger did not exist, or, what
would give entire security, from the bottom of the shaft, where
the air must be pure. A pipe or pipes of this kind running
through the principal passages, small upright tubes might arise
from it at convenient distances to the fixed lamps. A similar
mode might be extended even to the moveable lamps ; the flex-
ible tube attached to the lamp might be of such a length as
to reach to.a part of the mine where the air was known to be
pure ; or such flexible tubes might be adapted to branches fit-
ted with stop-cocks, and communicating with the main trunk.
Thus a system of perfect security, 1 conceive, would be attain-
ed. Independent:of the other circumstances diminishing any
hazard, there are here only two modes of communication with
the external air, from neither of which can any danger arise,—
by the upper aperture, and the lower tube. The former can
admit no air to the lamp within, and the latter must convey
merely pure air. Both, therefore, must be perfectly safe.

I have stated these diversities of method, merely to shew
how far the plan may be carried, where particular situations re-
quire it; and absolute security attained: but it is very proba-
ble, that in general they will be unnecessary, and that the sim-
ple mode first explained, of a tube connected with the lamp,
supplying air from the floor, will be sufficient.

This

a

AND ON PREVENTING ITS EXPLOSION. 41

This method, in its simplest form, affords another security,
that of avoiding the igniting of any stream or blast of inflam-

‘mable air, as it issues from the coal. This it often does sud-
‘denly, and-with great violence. A current of this air being

kindled in the common mode of lighting the mines, by the ap-
proach of a candle or lamp, is a frequent cause of explosions,
the stream of flame -extending to the mixture of inflammable
air and common air in the roof of the mine, and causing it to
explode. The inclosing of the lamp in the case, of course, pre-
vents any accident of this nature.

By these arrangements, adapted more or less to circumstan-
ces and situations, a system of lighting mines may be establish-
ed, I trust, perfectly safe, with any common care. And the
extreme simplicity of the plan, facility of execution, and eco- .

_ nomy, are recommendations in its favour.

It is scarcely necessary to enter on the details of the modes
of construction of the apparatus, as these are both obvious, and
admit of considerable diversity. I have given what appears to
be the best figure of the glass case for a fixed lamp, sufficient-
ly wide to prevent it from being broken by the heat, and not
too much so, so as to lessen the current and rarefaction of the
air. ‘he aperture, too, is adjusted to the same purpose. Ifa
lamp with oil be employed, it can either be suspended from
the top, or fixed on a socket from beneath; if a candle be
used, it must have a socket, which it may be requisite should
be a sliding one, to adjust it to the due height, as it burns

down. The glass cases may be protected from external inju-

ries by a wire netting. Fixed lamps will in general be less ex-
posed to risk than moveable lights, and by employing them in
sufficient number, few of the latter may be required. In all
the passages of the mine the former may be employed; and in
all cases where fixed lamps with a metallic tube reaching nigh

to the floor can be introduced, the method is more simple, and
Von. VIII. P. I. F i

18

42° ON THE FIRE-DAMP OF COAL-MINES,

is attended with !ess trouble, and requires less attention than
any other that can be used.

Some precautions may be necessary in kindling the candles.
or lamps. In the moveable apparatus this may be done at the
bottom of the shaft, or any other part of the mine where the
air must.be pure. The fixed lamps may be kindled in a simi-
lar manner, being supplied with a flexible tube at the bottom,
to be removed when they are transferred to the fixed tube, and,.
if necessary, with the additional precaution of stop-cocks to.
each. Various arrangements with regard to these will readily
occur... (Note D.) )

I have said that the accumulation of the carburetted hydro-
gen in the air of the mine, may be discovered by its effect.
on respiration. Its deleterious agency is well known. At the
same time, as in the greater number of situations, its addition
to the air must be gradaal, it will not exert its full deleterious.
power, but produce only such effects as will give warning of its.
presence,

Even before it acts this far, it will be eee by its smell.
Hydrogen in a humid state: has a sensible odour. The fire-
damp in mines is known by its smell ; the miner, in judging of
its presence, always advancing with considerable confidence
when no smell is to be peraiee ; and this criterion. must be-
come still more evident, when the person exposed to it js.
guarded from its early explosion, and it is thus allowed to ac-.
cuiiplaic to a greater extent. It is also sometimes apparent
to the eye, by the vapour which is diffused through it, forming:
a kind of mist, floating under the roof of the mine, and. fluctu-
ating with every movement of the air.

There is one other circumstance which has been aight
as a criterion, though, in- the usual mode of applying it, it
seems to be a very hazardous one,—what is called the candle

tope.

AND ON PREVENTING ITS EXPLOSION. 43

top. This is a yellowish-coloured diffusion of the light round
the flame of the candle, rising higher, and assuming a
greenish-blue colour when’ the quantity is considerable, and
when it is still larger, giving rise to a rapid succession of lumi-
nous points or flashes. ‘The miner, when judging from this of
the presence of fire-damp, advances cautiously in the mine, ob-
serving the appearance on his candle, by raising it slowly from
a certain height from the floor,—a circumstance I may remark
which shews very well the tendency to the accumulation of the
inflammable gas in the roof, and the comparative purity of the
air below. He thus advances, as far as he can with safety, and
_it is singular to what length the miners sometimes proceed with
this trial... This peculiar appearance seems to arise partly from
the extinguishing effect of the reduced air on the flame of the
candle; for a similar effect is produced in immersing a lighted
candle slowly in any gas unfit to sustain combustion ; and as it
extends so high, it must also partly arise from the imperfect
ascension of the inflammable gas. If any inflammable air
were to enter the lamp I have described, this appearance, or
something similar to it, would take place, even sooner, from
the rarefaction of the air, and probably the flame would be en-
tirely extinguished before any explosion occurred. It would
therefore give an equally sure indication with much more safe-
ty ; though it is also probable, that no air, so far impregnated
with carburetted hydrogen, could ever enter from the floor of
‘the mine while the atmosphere above was such that it could be

breathed. es
_ When the danger is suspected to exist, the state of the air in
any part of the mine may be accurately examined with great
facility, and entire safety. With a moveable lamp and tube,
such as has been described, or, if it were thought to give more
safety in extreme cases, with light obtained by the collision ot
; F2 steel

44 ON THE FIRE-DAMP OF COAL-MINES,

steel and flint, in the séeel-mill, as it is called, a person could
advance to any spot, empty a bottle of water there at any par-
ticular height from the floor, cork the bottle, and immerse the
mouth of it, inverted in water. A portion of the air would
thus be withdrawn, and at the bottom of the shaft, or at the
mouth of the pit, it might be tried whether it were explosive.
or not. Even if it did not kindle, the degree of the approach
to danger from the intermixture of a certain portion of the in-
flammable air, might be ascertained. ‘That a mixture of car-
buretted hydrogen and atmospheric air should be capable of
being inflamed, they must be in certain proportions to each
other. Not less, as Dr Tomson has remarked, of the carburet-
ted hydrogen than one-twelfth of the volume of common air
must be present ; and when it exceeds one-sixth of the volume
of the air, it ceases to explode. All mixtures in the propor-
tions between these will explode, but beyond these extremes
will not. If the air withdrawn from the mine for examination
does not explode, it may be discovered how near it is to the
first proportion at which this. will happen, by adding to differ-
ent portions of it, certain proportions either of hydrogen or at-
mospheric air, until an explosive mixture is formed. If the’
addition of a small proportion of hydrogen, for example, were
sufficient for this purpose, this would indicate the near ap-
proach to danger, by shewing that.a very little farther inter-~
mixture of fire-damp would render the air in that part of the
mine explosive. An excess of hydrogen, if it were present,
would always be hazardous, for although it might not form
properly speaking, an explosive mixture, still it would be in-
flammable. ‘I hese experiments are so simple, that the more:
intelligent miners or superintendents might be easily taught to
perform them. One of the most frequent causes of the unfor-
tunate accidents that have occurred, seems to have been the:
want,

AND- ON PREVENTING ITS EXPLOSION. 45°

want of any proper method to ascertain the extent of danger.
In many of them the aceumulation of the fire-damp was sus-
pected ; it was in trying to ascertain this that the explosion
happened, and it is astonishing to observe, in some cases, the
extreme imprudence with which this was done, by approach-
ing with a common candle. In mines: peculiarly liable to
such accidents, it might be well to have a regular system of
making such trials at stated periods. And this is more neces-
sary, when it is considered, that all methods of lighting that
may be proposed, are, strictly speaking, only calculated to les-
sen the danger from.accidental firing of the gas; and that, in
one point of view, they are a source of hazard, as giving the
idea of: greater security, and being liable, therefore, to lead to.
less, striet attention to ventilation.

When the accumulation of gas to a dangerous extent is as-.
certained, it may be drawn off by various methods. A com-
munication may be formed with a part of the mine in a state
of thorough ventilation, and the rapidity of the current of air
might be increased. Or, the foul,air-might be pumped out by,
a steam-engine, or by an exhausting machine, such as that pro~
posed by Mr Taytor*, brought to act on any particular part..
(Note E.)

It is not necessary, however, to enter on the details of the:
system, which, with regard to several of the contrivances, are
indeed sufficiently obvious, and which- might farther be varied
by local circumstances, and be improved by a: knowledge of
these, and by experience. My object has been. merely to state,
the general method, and explain its principles, with any col-
lateral obseryations which appeared to. me to. be of import--
ance.

It

* Tromsoy’s Annals, vol. iii. ; or Philosophical Magaziie, vol. xxxviii.

46 ON THE FIRE-DAMP OF COAL-MINES,

It is farther obvious, that the mode of producing illumina-
tion by coal gas may be connected with this method, at least
so far as regards the fixed lamps. The gas might be prepared
by a furnace, at a part of the mine where there would be least
hazard from carrying on the operation,—at the bottom of the
air-shaft, for example, where a strong current of air moves out-
wards, and the gas might be conveyed through a main trunk,
to pipes terminating by a small aperture within the glass-case.
Its combustion, as it issued from the aperture, might be sus-
tained with safety by the current of common ‘air, supplied in
the mode already described. A very brilliant illumination
might thus be obtained; and from the peculiar advantages of
situation, this might be done so economically, that it might
render moveable lamps, to which the method could not well
be applied, unnecessary. It might even become a source of
advantage, by getting rid of much of the waste coal, and con-
verting it into coak. It is possible, however, that the attention
required in the process, and its interfering with the operations
of the mine, might, independent even of any supposition of ha-
zard, render the propriety of its introduction doubtful.

‘Tne general method, I may add, will prove equally effectual —

in obviating the danger from Choak-damp, carbonic acid gas,
the other evil which miners dread, and which often also occurs
in caverns, subterranean passages, and other situations. From
its specific gravity being so much greater than that of atmo-
spheric air, it is known to remain nearly at the floor, and to ex-
tend very gradually upwards. A person, therefore, may ad-
vance with safety, where it is present, by the precaution of

holding

AND ON PREVENTING ITS EXPLOSION. 47

holding in the hand a candle within a glass case, having a tube
attached to it supplying air from near the floor. The supply
of air to support the combustion being thus from beneath, the
presence of carbonic acid gas to any hazardous extent would
soon be discovered, by the flame of the lamp becoming fainter,
and being at length extinguished, while the respiration of the
individual would not be affected: And. by.raising the open
end of the tube to different heights from the ground, the ex-
tent to which the atmosphere of carbonic acid reached would
be ascertained.» By establishing in mines in which the choak-.
damp is liable to occur, a system of lighting similar to that
which has been described, the danger from it would be effec.
tually obviated... )

ik

NOTES.

48 ON THE FIRE-DAMP OF COAL-MINES,

NOTES.

Note A. page 2.—The production of fire-damp is much less
considerable in the Scotch collieries than in those of the west,
or the north of England. It would be important to discover
the cause of this, but it is not very obvious. Probably it arises
from the smaller scale on which they are wrought. In some
of them, however, it does occur, though in quantities not so
considerable, but that it is usually carried off by the common
mode of ventillation, or by firing it as it begins to accumulate.
In the mines in Ayrshire, it is the practice to fire it daily.
Within these few years, explosions from it have in different
cases been productive of fatal accidents, some of them, espe-
cially in the mines in West Lothian and Stirlingshire, to a
considerable ‘extent. ;

Note B. page 4—No question can be more important in re-
lation to the subject of the fire-damp of mines, than that with
regard to the causes of its production. The facts stated in the
text prove, that it is not entirely from the old wastes that the
gas is discharged, though they may afford a large quantity of
it. Its evolution might be considered as a circumstance in part
connected with the original formation ; the gas might be sup-
posed to have been formed with the coal, to be confined by
pressure in its mass, or its interstices, and to be liberated as
the pressure is removed by the working. The density of the
mass of coal, however, can scarcely be supposed to be such, as
to have confined the gas from its first consolidation, and it

must

AND PREVENTING ITS EXPLOSION. 49

must therefore rather be regarded as a new and continued pro-
duction. There is no operation from which, under this point
of view, it can be derived with so much probability as from the
slow decomposition of water permeating the coal ; and the con-
nection of the production of carbonic acid with the carburetted
hydrogen, seems to prove that this is its origin. That water
transuding slowly through a mass of coal, and existing in it in
some measure under pressure, will be decomposed, is, from the
consideration of the general agency of water on carbonaceous
substances, extremely probable. The evolution of the same gas
from marshy situations, there is every reason to believe, de-
pends on the decomposition of water by carbonaceous matter ;
and the occurrence, not unfrequent, of large masses of small
coal accumulated at the mouths of the pits, and exposed to
humidity, taking fire spontaneously after a certain time, can
scarcely be ascribed to any other cause than to such a decom-
position, and may therefore be regarded as a proof of it.
There are circumstances, too, connected with the production of
fire-damp which seem to prove that this is its origin. Thus it
does not occur in all coal-mines; in some it is abundant, in
others it is almost unknown ; and this seems to be considera-
bly dependent on the state of humidity in the coal. In the
collieries in this country,—for example, fire-damp scarcely ever
occurs in those of Mid Lothian; while in those of West Lo-
thian, of Stirlingshire, Fife, and Ayrshire, it is not an unfre-
quent occurrence; sometimes to such an extent as to have
-been productive of considerable explosions, and in some of
these mines its evolution is nearly constant, so that it is a re-
gular practice to remove it by firing it. I have been able to
discover no cause for this peculiarity, but the comparative state
of dryness and humidity. It is not owing entirely to the depth,
for this differs little ; in some of the mines of Mid Lothian,

Vou. VIIL P. I. “G the

~,

50 ON THE FIRE-DAMP OF COAL-MINES,

the depth is 57 or GO fathoms ; in the Grange Colliery, in West
Lothian, where an explosion happened some time ago, the
depth is about 50 fathoms ; and in the Ayrshire mines, the first
bed of coal is at a depth of 30 fathoms; the second at a depth
of 26 below this, not deeper, therefore, than that of the Mid
Lothian collieries, where the gas does not occur; and farther,”
from the upper bed of the Ayrshire coal, fire-damp is given
out as abundantly as from the lower. But the collieries of
Mid Lothian are perfectly dry ; the coal being what are called.
edge seams, that is, in strata vertical, or- highly inclined, a dis-
position which allows. the water to pass off more readily. In
Ayrshire again, at Borrowstounness, and at Valleyfield, where.
there is the generation of fire-damp, I am informed there is
much water, which seems even to percolate the-coal. This is.
particularly the case in Ayrshire, the water dropping from the
wall of coal, and a current or blower as it is called, of fire-damp
sometimes escaping with water. The still greater production
of fire-damp in the English mines, is probably owing to the
much larger scale on which they are wrought, and to the deep
and extensive workings being favourable to. the collection of
water. It accordingly appears, from the accidents which
have repeatedly happened from water bursting into mines, that
it is accumulated in old pits and excavations in immense quan-
tities, and that it transudes through the mass of coal. The
last accident which occurred, that at the Heaton Colliery, in
which seventy-five individuals were destroyed from the burst-
ing of water into. the mine, is a melancholy proof of this.
These causes, too, particularly the depth. of the workings, fa-
your the accumulation of the gas. ‘This. in some measure ac-
counts for the accidents from. explosion having become more
frequent in these mines, notwithstanding the improvements in
their ventilation, and gives some ground for the fear that its:
accumulation:

AND PREVENTING ITS EXPLOSION. 51

accumulation may still increase. The more numerous and ex-
tensive the excavations become, it is justly remarked, in a pam-
phlet published bythe Literary and Philosophical Society of New-
castle, the greater will be the difficulty of guarding against sur-
rounding wastes filled with water, or carburetted hydrogen, or
carbonic acid gas; and when, at a future period, it shall be
found necessary to work the lower seams in this coal-field, the
operations of the miner must be carried on under immense ac-
cumulations of water. If these views be just, the propriety of
impressing on the coal proprietors the necessity of conducting
the workings en a better system than has hitherto been follow-
ed, will be obvious; and from the apparent indifference of
many of them on this subject, the propriety of legislative inter-
ference to regulate the economy of the mines, which has been
repeatedly suggested, will scarcely be questioned.

Tt is a curious circumstance, that in those mines in which
the fire-damp does not occur, the production of choak-damp,
or carbonic acid gas, is not unfrequent. Thus it often occurs
in the Mid Lothian collieries, and sometimes at no great
depth.

Note C. page 37.—It is been said, that the infammable air
sometimes issues from the floor of the mine, and this has been
stated as a sufficient objection to the method I have proposed.
The fact is, that it seldom comes from the floor, but usually
from the sides of the wall of coal ; and in general even the dis-
charge is rather from nigh the roof than from beneath, as must
indeed be the case in the escape of an elastic fluid from an im-
perfectly solid mass. But even if it did issue from the floor
much more frequently than it does, it does not remain there,
but rises to the roof, where the accumulation of it, and the
mixture of it with the atmospheric air which renders it explo-

G2 sive,

§2° ON THE FIRE-DAMP OF COAL-MINES}

sive, uniformly take place, as all the facts connected with the
state of the air in the mines prove; nor can any accumulation
of it take place, which shall reach the floor of the mine, but by.
its filling the space from the- roof downwards, mixed more or
Jess with the atmospheric air. All that is necessary, therefore,
is to guard against the chance, extremely small in itself, of the:
open end of the tube being in the direction of a stream of the
gas, if at any time it should issue from the floor, and this is,
easily done by the methods stated in the descriptions, of the,
tube being turned up at its extremity, or of its being closed for,
the height of two or three inches, with apertures above this
height, to-admit the air. Any small quantity which might be
brought by the current of air entering the tube must be unim-
portant, and any danger from this source must require such.a
combination of circumstances as may well be expected never
to occur,—that of the tube being in the direction of the cur-
rent of gas,—of the mixture of it. with atmospheric air being in
that limited proportion when it reaches the flame of the lamp
in which it explodes, and of the whole air at the floor of the
mine being also in that state in which it will explode; and
all this independent of the circumstances, that by any such
mixed air passing into the lantern, the flame of the lamp will
be extinguished’ instead of explosion happening, and that ex-
plosion, even if it did oecur, would not be conveyed along this
length of tube.

“The same arrangement, with regard: to. the tube, obviates
another possible inconvenience;—that of the: entrance of car-
bonic acid gas, which, from its greater specific gravity, may
sometimes occupy the floor of the mine. It seems scarcely
ever to be accumulated to this extent in mines in which fire-
damp is generated ; and if it were, its entrance into the lan-
tern, would be productive of no other accident than that of

extinguishing

AND ON PREVENTING ITS EXPLOSION. 53

extinguishing the flame. But even this is easily obviated, by.
admitting the air at any height from the floor which may be.

found requisite.

“Mats D. page 42.—To. the observations in the text, on the
construction of the lamp, a few details may be added.

The principal circumstance requiring adjustment, is that of
the size of the apetture by. which-the heated air escapes. If it
is not sufficiently wide, the flame is faint, and'on the move-
ment of the lamp becomes unsteady, and is liable to be extin-
guished. If it be too wide, there may be some risk of a cur-
rent of air entering the lantern by it, especially if the under
tube is not sufficiently wide, by which the whole security from
the method would be lost. The due size is most easily found, by
affixing to the aperture»at the top a conical tube, and cutting
this down in-successive trials, until. the diameter is, attained at
which the flame is steady and bright., It is-not easy to give. a
precise dimension, as the flame is dependent.on the breadth
and height of the wick, the purity of the oil, and the state of |
the air; but I find that in a lantern of the. size of the move-
able one mentioned in the text,—five inches in height by
three in width, with a flat cotton-wick three-tenths of an inch
broad, and burning so. as. to consume about two ounces of oil
in six hours, the diameter of the aperture being a.very.little
less than half an inch, admitted of the flame being steady and '
bright when the combustion was fully established. In the
mine it may be required to be a little larger. When the lamp
is kindled, it remains for a minute or two more faint, and if
moved hastily i in this state, is liable to be extinguished.. One
aperture is preferable to two or three smaller apertures, as there
is less risk of any counter-current ; and to guard also against
this in. any movement of the lamp, it is proper to have the —

opening

54 ON THE FIRE-DAMP OF COAL-MINES,

opening in the form of a short tube. The heat of the air is-
suing from an aperture of this size, with a flame such as has
been described, I found to be 370°, the bulb of the thermome-
ter being in the current exactly at the orifice ; when introdu-
ced entirely within the aperture, and immediately above the
flame, it rose to 465°. Air of this temperature, it is obvious,
cannot inflame fire-damp, or any mixture of it.

No very accurate adjustment is required with regard to the
size of the tube conveying the air into the lantern. It is suf-
ficient to have it wide enough; the state of the flame is then
regulated entirely by the size of the upper aperture, and any
slight excess of width in the tube beneath is of no importance.
I find that with a lantern and lamp of the above size, a tube
‘three-fourths of an inch in diameter interior measure, and three
feet and a half in length, answers very well. This circum-
stance, of no accurate adjustment being necessary, gives an ad-
vantage to this method in actual use. Where the safety of the
lamp depends on such an adjustment, it is difficult to construct
it in such a manner that it shall burn with a bright flame, and
steadily, so as not to be liable to be extinguished by move-
ment, or by the least failure either in the current of air, or in
its purity. The bringing the air from the floor renders any
such adjustment unnecessary, and allows, therefore, of a more
bright and steady flame being produced with entire safety.
And by the lamp being thus always supplied with the purest
part of the air, it will continue to burn where any safety-lamp
on a different principle must be extinguished, and of course
will enable the miner to work in situations where no other will
be of any use.

In fixed lamps, the length of the tube must be regulated by
the height of the passages. The thickness of the two beds of
coal at Newcastle is about six feet each. But it is unequal,

and.

AND PREVENTING ITS EXPLOSION. . 52°

and in some places is not more than four feet. On the other
hand, the occasional falling of the roof forms dome-like cavi-
ties above this height; it is in these that the inflammable air
chiefly accumulates, and in the lower passages or workings,
where they are open, the draught of air must in general pre-
vent it from being collected. Hence the limits to the eleva-
tion of the lamp, and of course tothe operation of the principle
on which the method is founded, are less than they at first ap-
pear; though even. the height of three, or three feet and a
half from the floor, while it is probably best adapted to the ne-
cessary illumination, will give the requisite security.

A. lamp with oil is more convenient than a candle, as requi-
ring no adjustment. with regard to the wick; and by the com-
mon. contrivance of a. plate with a screw-on the aperture, the
oil is prevented from being spilt, on any occasional inclination
of the lamp. The usual time of a. miner’s. work is six hours ;
the lamp, of the size just. now mentioned, with fresh oil and.
wick, burns seven hours. The miner, therefore, may take it.
with him newly trimmed, and the lantern need. never be open-
ed in the mine, by which any risk from the communication of |
its flame to the surrounding air may be avoided. If it were ne-
cessary that it should burn for a longer period, it might, with-
out any inconvenience, be made of a larger size ; and the wick
might be made sa.as.to admit of being raised by. a contrivance.
similar to that of Arcann’s. All the joinings of the case or.
lanthorn, it is obvious, ought to be as close as possible.

By employing a metallic lantern, with a lens of very thick
glass in front, the risk from breaking, which is incurred when
a glass case is used, is avoided. This construction has other:
advantages. It affords a great deal of light in the most fayour-
able manner; the illumination. being directed with less loss on
the space where it is required.. Where the situation admits of

i,

56 ON THE FIRE-DAMP OF COAL-MINES,

it, a lantern of this kind can be made to project light in a
straight line to a great extent, and illumination may be thrown
into a passage, or along the side of a wail which is to be work-
ed, by its being placed at one extremity. This may not only
have the advantage of economy, but of greater safety, so as te
render this method proper to be employed on this account
alone, independent of any other consideration ; for the lamp
being placed at some distance from the miner, the risk is
avoided from the concussion arising from his working, from
any fall from the roof, or from the sudden discharge of the in-
flammable gas from any opening in the coal. Iumination
may also be thus obtained, in situations where, from imperfect
ventilation, it is difficult to support the combustion of a lamp,
such as the close extremities of passages or of new workings.
These are the very places, too, which are more peculiarly liable
to the accumulation of the inflammable air; and in both re-
spects, therefore, the advantage is obvious, of a mode by
which, where the direction of the working admits of it, (which
it will almost always do to a certain extent,) light may be
thrown from a distant spot, where the same difficulty and the
same hazard do not exist. Lastly, In ascertaining the state of
the air in passages where danger is suspected, or in exploring
them after the accident of an explosion, the same method will
give greater safety. Where a more diffused light is wanted,
this is easily attained by the surface of the lens being more or
less scratched.

Note E. page 45.—When the workings of a mine are car-
ried to a considerable distance from the course of the current
of air, without a corresponding shaft being made, the ventila-
tion becomes very imperfect. In this case, it is stated in a ve-
ry candid communication by Mr Scort, (Edinburgh Journat,

December

AND ON PREVENTING ITS EXPLOSION. 57,

December 1815,) that the lamps burn with more brightness:
near the floor than near the roof of the mine; the lamp, 'there-)
fore, with the tube, will be adapted to such situations, or/at
least the cireumstance of the air being brought from the: floor:
will counterbalance any obstacle from its being inclosed, and
will allow it to burn as well as an exposed lamp would. Inthe:
Scotch coal-mines in general, the system of ventilation appears
to be even less perfect than it is in the mines in the»northsof
England, probably from ‘the same necessity not having ‘existeds)
for rendering it equally perfect, as the production of fire-damp’
is so much less abundant. The circulation of the air im them
is often so languid, that a method of lighting by a close lamp
would perhaps be attended with difficulty, at least if it were
necessary to place the lamp in such situations, which, however,
the contrivance of employing a lantern with .a lens, in some
measure would obviate. The English mines present the com-
bination of a more perfect ventilation with. the constant pro-
duction of enormous quantities of fire-damp ; the object, there-
fore, is to guard against explosions from the accidental accu-
mulation of the gas, while, at the same time, the general plan
of ventilation admits of this being more easily carried into ef-
fect. A singular method, which shews both the imperfect
ventilation, daid the moderate extent within which the gas is
generated i in the Scotch mines, has been practised,—that of fi-
ring the quantity accumulated at a stated. period,—in some ©
mines daily. A miner enters the mine with a lamp inclosed
in a.lantern ; he advances as far as is proper, holding it as low
as possible, sel lying down on the ground, or sometimes even
in atrench dug i in the ground; he remoyes the lamp from the
lantern, and raising it, or advancing it towards the closed ex-
tremity of the working, where the gas is collected, fires it. Mr
Scorr, in the a achrivicatieu referred to, proposes a plan of

Vou. VIL P. I. H eee
: 3

‘™

58 ON THE FIRE-DAMP OF COAL-MINES,

firing the gas as it collects, by a lamp of a particular construc-
tion, suspended nigh the roof. This would be safer than the
old method, by which the workmen are sometimes injured, and
which, whenever the production of the gas becomes consider-
able, is evidently impracticable. But the exhausting machine
noticed in the text, (page 45.) may always be applied with suf-
ficient effect, and where the gas is slowly collected, must be
preferable to any other method, where a current of ‘air cannot
be completely established. In the Hurlet mine, near Paisley,
it has been employed with entire success, and on so small a
scale, that it is worked with a hand pump. The cylinder ex-
hausting the air is 23 inches in diameter, and it makes a 13
inch stroke 13 times per minute; it discharges, therefore, in
that time, 40 cubic feet of air. It is worked by a boy, and on-
ly as it is required. Tubes of tinned iron are connected with
it, which are prolonged as the excavation extends.

Description of the Figures. (Page 36.)

Fig. 1. Plate 1. represents the Fixed Lamp.

A, The glass case within which the candle or lamp is placed

in a socket, with the aperture at the top, of a sufficient
size to admit of the escape of the smoke and heated air.

B, The tube of tinned iron, or of copper, which enters beneath

the socket, conveying air from-the floor to support the

flame. To shew the length, it is represented in two parts,

and at the under extremity it is turned up to the height

of three inches, to attain the advantages explained, p. 52.

; Fig.

PLATE I.

Engraved for the Royal Society Thar! Vo 8.»

age, 58.

Engraved by Wk D Lear Bain

AND ON PREVENTING ITS EXPLOSION. 59

Fig. 2. represents the Moveable Lamp.

A, Is a lantern of tinned iron, five inches in height, and three
inches in width, with a glass lens a, three inches in diameter,
projecting half an inch in front. The lamp 4 is introduced
at an opening behind, which i$ closed with a cover secured.
by a wire, passing into a small groove or tube, as repre-
sented at c; d is the aperture in the small dome at the
top, by which the smoke and air escape; e is a small pro-
jecting plate to disperse the current of hot. air; f the:
handle, which rises from the double back.

B, Is the tube of leather, with a spiral wire within, to prevent

its compression, which conveys the air to support the

flame ; three-fourths of an inch in diameter, and from three
to four feet long, and represented in two parts, to shew its
length. It is adapted by a screw to the short projecting
tube g, at the bottom of the lantern ; and the lamp within
resting on a plate at the height of half an inch from the
bottom, the air enters beneath this, and rises by its sides.

‘To the under end a tin tube / is adapted, closed at the end,

with apertures in the sides, at the height of about three

inches, to admit the air; this having the same advantages
as the turning up of the tube in the former figure, and in.

a moveable lamp being more convenient.

H2 IV.

‘— a,
a+)

aa serving serge

de "dai efi Saati Fas

é seceftanel Ate one od
“att taicwige trilgediny vit one
pepotisih ni eedloat sauder .o pe ey
Basidbiesiei ai} qual ole
osuone teyoo- diy he
pio. Bhs Ml ay Hace
addin. Vivwrgne sath sakes
~0n) Hsetire ae i 9. 2 oyagond shod

“aati hous fogitingmanst hy}
: 4 + rie vicboncat ine

tf ioe ,
aa:

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St tine
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VV. On the Lines that divide each semidiurnal Are into Six
equal Parts. By W. A. gpa Esa. F. R. S. Lonp. &
En.

i

[Read 3d June 1816.]

‘HE divisions of the day which different nations have em-

i ployed, are denoted by hour-lines of various kinds on the

‘sphere. Of these hour-lines, drawn on.a supposition that ne-
glects the inequalities of the Earth’s motiGe, there are three
Jinds.

_ The first kind, denotes hours counted from nis sot equal
to each other at all, declinations of the sun. ‘These lines are
great circles on the sphere, passing through the poles of the
equator, and every pair intercepting a similar arc on each of
the parallels. Of this kind: are the hour-lines of sidereal time,
counted from the meridian, and the hour-lines of solar time,
counted from the meridian.

The second kind of hour-line denotes hours counted from the
horizon, equal to each other in duration at all declinations of the
sun. These lines are great circles which touch the greatest vi-
sible parallel on the one hand, and the greatest invisible paral-
lel on the other; each pair of these great circles cuts off a si-
milar are from si diurnal arc. They are the horizons of

different

62 ON THE ANTIQUE HOUR-LINES.

different points of the parallel which passes through the ze-
nith. The Italian hours counted from sunset, and the Ba-
bylonian hours counted from sunrise, are denoted. by lines of
this kind.

The third kind of hour-line, and of which it is proposed to
speak more particularly here, denotes hours varying in length
as the declination of the sun varies, each hour being one-sixth
part of the semidiurnal arc, whether that arc be a smaller por-
tion of the circumference, as in winter, or a greater, as it is in
summer. On the oblique sphere these lines are not great cir
cles, and each adjacent pair intercepts @ dissimilar arc on each:
semidiurnal arc. This kind comprehends the hour-lines of the-
ancient Greeks and. Romans, which denote hours called hecte-.
moria *, that is, sixth parts of the semidiurnal: arc.

The curvature of these lines is visible when they are drawn
on a globe; it is likewise seen in their gnomonic projection, in
the following manner.

Figure Ist is a perspective: view of the lines which intercept
one-sixth part of each semidiurnal arc ; the point of sight is the
centre of the sphere ; the plane of projection touches the sphere
at the pole of the equator, and is therefore parallel to the equa-
tor ; the latitude is 66° 30’; at this latitude the whole of each
hectemorial hour-line is gone over by the sun in a year. This.
perspective view is the same as the central or gnomonic pro-
jection of the sphere on the inside of a plane which touches the
sphere at the pole of the equator; it forms an inferior equi-
noxial dial for the latitude 66° 30, when placed parallel to the
equator, with its inscribed surface downwards, and the point
xxiy. elevated.

In

* ‘Exlnudgio, sexta pars, sextarius, is used by Protomy. The lines that separate.
the hectemoria from each other are in this paper called hectemorial lines,

ta

ON THE ANTIQUE HOUR-LINES. 63

In this view the projections of the parallels are circles, and

equal arcs of the parallels are represented by equal arcs of their

projections: the construction of the lines which intercept one-
sixth part of each semidiurnal arc, is therefore performed by
dividing the projection of each semidiurnal arc into six equal
parts, and connecting each point of division with its corre-
sponding points on the projections of the other semidiurnal
arcs. .

‘In figure Ist, these hectemorial hour-lines are seen to con-
verge at that point of the meridian which is marked 66° 30’.
This is the point of contact of the horizon, and greatest unseen
parallel ; it is s also the point where the.mid-day part of the me-
ridian cuts the horizon. At this point the semidiurnal arc is
indefinitely small, and therefore the lines which divide it into

_ six parts must be indefinitely near to each other, or, in other

words, must converge.

At this point of convergence each hectemorial line is incli-
ned at a considerable angle to the meridian. As the line pro-
ceeds, the inclination becomes less, till it is nearly as small as
the inclination of the astrenomical hour-line, which this hecte-
morial line cuts at the equator; and the hectemorial line on
this projection is asymptotic with that astronomical hour-line.
For the distance of their intersection from P, measured on the
plane of projection, is infinite, being equal to the distance of
the intersection of the equator and plane of projection, two
planes parallel to each other ; and however far the projection is
extended, the two lines approach indefinitely, but do not
meet.

Take, for example, the third hectemorial line HS (in the
figure on the margin) which cuts the ninth astronomical hour-
line at the equator; the projection of a great circle which in-
tersects the ninth astronomical hour-line at the equator, is a

straight

64 ON THE ANTIQUE HOUR-LINES.

straight line parallel to the ninth astronomical hour-line on

this projection; but the third hectemorial line is continually

approaching to the ninth astronomical hour-line ; the distance-
between them at the horizon being HD = are. 45° x tan. polar
distance, and afterwards it is (arc 45° —'} semidiurn. arc) X tan.

polar distance of the star ;\ + semid. are increases, but never at-
tains to be 45°, so that the distance never becomes equal to.
nothing, and tan. polar distance increases indefinitely.

All great circles are seen under the form of straight lines in
this projection of the sphere ; and therefore the projection of
one great circle cannot be an asymptot to the projection of
another ; it follows, that the projections of the hectemorial
lines are not projections of great circles.» Ifa straight line be
drawn through the point H, (in the figure on the margin,) cut-
ting off a given aliquot, one-half, for example, from a semi-
diurnal are on the projection, it will cut off a smaller aliquot.
from the meridional extremity of the other semidiurnal arcs,
in proportion as they are nearer to the point H; and in order
that a straight line drawn from H may cut off the same aliquot
part from several concentric arcs
which are included. between the
versed sine HN and sine HO of the
outer arc, it is necessary that the
chords of these arcs be parallel to
each other; which happens ‘only
in the case where all the arcs are of
90°, then H coincides with P, and
then the straight line which cuts off
the same aliquot from every arc, is a line passing through P
the centre ; and this sole case is a central projection of a sphere
so placed, that each semidiurnal arc is 90°, the poles of the
equator being in the horizon. In ‘this position alone are the

ey hectemorial

ON THE ANTIQUE HOUR-LINES. 65

hectemorial lines great circles, and in this case they coincide
with the astronomical hour-lines, and pass through the poles
of the equator. When the poles are thus in the horizon, all
the three kinds of hour-lines coincide. When the pole is in
the zenith, the second kind or horizontal, and the third or
hectemorial hour-lines cease to be, because then the horizon
does not cut any of the parallels into diurnal and nocturnal
arcs.

To express algebraically some of the above-mentioned pro-
perties. Let the abscisse 2 be taken on the meridian HM,
and the ordinates y at right angles to the meridian, the cen-
tral projection g gives

n :
ay SIN. 63 tan. polar dist. star,

se

si Or OFT... 8 n ee .
“= | COs. & S—COS. 8 i tan. pol. dist. star.

es i hee P oy)
PH is cos. ; the cosine of the semidiurnal arc. PM is cos. rae
iv } + ‘

the cosine of the fractional part of the semidiurnal arc. MS
Bee: : ;
is sin. & 8; the sine of the fractional part of the semidiurnal

arc, PS is tan. pol. dist. star ; the tangent of the polar distance ~
of the star. m is one of the numbers 1, 2, 3, 4, 5; it is 5 for
the curve that contains the first and eloton tie hectemorial line ;
4 for the second and tenth, and so forth.

it n
sin. =
vie hes is not tl tion of a straight li

- s not the equation of a straight line, except
“COS. 6 7. 5—COS. Sik

in the case where cos. s = 0, that is, whet the semidiurnal arcs
are all 90°, the poles being in the horizon.

Vou. VIL P. I. I go

66 ON THE ANTIQUE HOUR-LINES.

Liat 0 sp : :
y = sin. G5 tan. pol. dist. in this equation, when the describing

diameter arrives at H, sin. g°= 0, that is, the curve cuts the
axis of the absciss2 at H, and when the describing diameter

‘ ee :
passes onward, the sign of e538 changed, expressing that there:

are two similar and equal branches, one on each side of the
axis of the abscissz.

n ee
Cos. 6° has only one value, because g ° 18 never so great

as 90°, and its cosine, therefore, does not Recore =9@ which:
it must do before its sign changes.

If a central projection of any one forenoon hectemorial hour-
line, and of the afternoon hectemorial line equi-distant from:
the meridian, be drawn for
different heights of the pole,,
it will be seen that these two
hectemorial lines form for
each height of the pole an
equicrural curvilinear branch,
including within it the cor-
responding hectemorial lines
for a higher latitude, and all of them included mci two astro~
ifaraieal hour-lines as asymptotes. With these asymptotes the
pair of hectemorial lines coincides, when the poles are in the
horizon. The figure in the margin represents the equicrural
curves formed by the: third hectemorial hour-line and by the
ninth, which is the afternoon branch equi-distant from the me-
ridian.

The curved branches are drawn for every ten degrees of la-
titude from 30 to 70 inclusive ; the rectilinear asymptotes with-

in.

ON THE ANTIQUE HOUR-LINES. 67

in which the curves are contained, are the ninth and fifteenth
astronomical hour-line counted from midnight.
From figure Ist it may be collected, that the asymptotes of
each hectemorial line are as follows :
(!

The equicrural curvilinear branch, | has for asymptoles the astro- | which compre- |

composed of the hectemorial lines nomical howr-/ines, counted | hend an angle
From midnight, of

First A,and Eleventh IA,) VII. and XVII. 150°

Second B,andtenth I,} VILL. and XVI. 120°

Third Tr, and ninth ©,) IX.and XV. 90° |

Fourth A, and eighth 4, X. and XIV. 60°

Fifth, E, and seventh Z, XI. and XIII. 30° “aoe

Figure 1st represents the portions of the day hectemorial
lines which touch the greatest invisible parallel for the latitude
66° 30’; these are the winter portions. In-order to delineate
the portions which touch the greatest wholly visible parallel,
or the summer portions, the projection is made on the plane
which touches the sphere ‘at the depressed pole ; this projec-
tion is exhibited in figure 2d, which contains portions of
curves, each of which is similar and equal to the curve of the
sane hour in figure Ist, but differently placed. It forms a su-
perior equinoxial dial for 66° 30’, when placed parallel to the
equator, with the inscribed surface upwards, and the a XXxiv.
elevated. Th tia

- However extended the plane of projection touching the
sphere at the pole be, still it will not contain the portions of
the hectemorial lines that are near the equator. To have these,
the plane of projection is taken at right angles to the equator,
in touching thie Saaunig at the depressed intersection of the

ms Tern 12 equator

68 ON THE ANTIQUE HOUR-LINES.

equator and meridian. This projection, which is drawn at
figure 3d, contains some of the hectemorial lines from the point
of their contact with the greatest wholly unseen to the points
of their contact with the greatest wholly seen parallel. It forms
a polar dial for the latitude 66° 30, when placed parallel to the
plane of the sixth astronomical hour-line.

The lines thus drawn in the above projections are curved ;
consequently they are not the projections of great circles ; nei-
ther are they the projections of small circles, for if they were,
they must necessarily touch the horizon at its intersection with
the mid-day portion of the meridian, because in that point the
hectemorial lines converge, and do not go on the other side of
the horizon. Now, if small circles so placed, be drawn on the
sphere or projected on a plane, it will be found that their
course deviates entirely from the course of the lines bounding
the hectemoria. The hectemorial lines, therefore, do not coin-
cide with small circles on the sphere, nor with conic sections;
on the central projection.

‘The projections above exhibited shew that each pair of hee-
temorial lines for a given meridian and latitude, is an equicru-
ral curved line ; but this is only one branch of an entire curve,
because the diameter whose extremity has traced a pair of
these lines on the surface of the sphere, has still to complete
its revolution, which is.done when it has arrived by progressive
and continuous motion at the point from which it set out. In
order to accomplish this with the same kind of motion with
which they described the first branch, the extremities of the
diameter leave the two parallels that touch the horizon, and
proceed to cut off the same aliquot part from the semidiurnal
arcs belonging to this second point of departure, as they had
done from the semidiurnal arcs of the first point of departure ;
the second point of departure is to be considered as the mid-
day point of a horizon on the opposite side of the equator to

the

ON THE ANTIQUE HOUR-LINES. 69

the first. The extremities of the diameter, after having in this
way passed several times to and fro between the greatest whol-
ly unseen and the greatest wholly seen parallel, aud after ha-
ving completed one or more circumferences, attain precisely
the two opposite points from which they set out, having form-
ed two opposite re-entering curves on the surface of the sphere,
and afterwards, in every subsequent revolution, the extremities
of the diameter only retrace the lines they had described in
their first revolution. The nature of the motion is such, that
the describing points cannot go beyond the two parallels which
touch the horizon, because there are no semidiurnal arcs be-
yond these parallels, and the constitution of the hectemorial
lines, consists in cutting the semidiurnal arcs.

Whilst the extremities of the diameter describe two re-en-
tering curves on the surface of the sphere, the diameter itself
describes two opposite re-entering curved surfaces, whose com-
mon vertex is the centre of the sphere. These two opposite sur-
faces coincide with a straight line directed to the vertex, but

do not coincide with a straight line in any other direction. In
this respect they resemble a conical surface, and they may be
considered as a kind of opposite cones with an undulated sur-
face, included between the outer surfaces of the two opposite
circular based cones that touch the horizon; the apex of each
undulation being applied alternately to the one and to the
other of these right circular based cones, so that as the com-
mon vertex of all these cones is the centre of the sphere, each
_of the two opposite undulated cones has two similar and equal
_ bases or right sections, the one above the centre of the sphere,
_the other below it. Each of these bases is an uninclosed curve,
- composed. of many equiecrural branches, each equicrural branch
haying for asymptotes two straight lines that intersect in the
»axis ; these two right sections are indefinitely extended ; and

the

70 ON THE ANTIQUE HOUR-LINES.

the bicrural branches of one right section are alternately placed
in respect to the branches of the other right section.

The undulated cone belonging to each of the five hectemo-
rial lines is different from that of the others. The five upper
bases are represented in figures 4th, 5th, 6th, 7th, and 8th,
drawn according to the rules of the central projection, on a -
plane parallel to the equator, for the latitude 66° 30... The
full lines are the upper base of one of the two opposite undu-
lated cones; the dotted lines are the upper base of the other
opposite undulated cone. These bases or right sections are
each made up of a pair of hectemorial lines for a given lati-
tude, forming one equicrural branch, and of similar and equal
pairs for other points of the same panei of latitude and of the
opposite parallel.

In order to present to the eye the image of one of the un-
dulated cones, figure 9th is drawn. It is a shaded view of one
of the two opposite conical surfaces to which the 3d and 9th
hectemorial lines belong, for the latitude 66° 30’. The point
of sight is in the plane of the equator; the distance is two dia-
meters from the centre of the sphere.

The sections of the undulated cones, by a cylindrical seeds
circumscribed round the equator, are made up of the same
branches ; they are complete and re-entering, whereas the sec-
tions by a plane are always incomplete. These cylindrical
sections are laid down in figures 10th, 11th, 12th, 13th, and
14th. The cylindrical surface is here unrolled ; when restored
to its cylindrical form, the inscribed curve is re-entering, and
without a break.

Where the number of degrees between the upper apices of
each undulation is a divisor of 360, the undulated cone is com-
pleted in one circumference, because at the beginning of the
second circumference, the generating diameter enters into the

path

ON THE ANTIQUE HOUR-LINES. 71

path it had described in the first; this is the case with the
three undulated cones which contain the third, fourth and fifth
hectemorial lines, figures 6th and 12th, 7th and 13th, 8th and
14th.

‘The number of degrees between the meridians of two adja-
cent upper apices, is equal to twice the distance between the
two adjacent sides of each undulation measured on the equa-
tor, or to four times the distance of the equatorial point of
the hectemorial line from the meridian measured on the equa-.
tor. :

Where this number of degrees between the meridians of tlre
upper apices is not a divisor of 360, but of a multiple of 360,
the revolution is completed in as many circumferences as there
are units in that multiple; because the generating diameter
does. not enter into its former path till it has described that
number of circumferences. The undulated cone which con-
tains the second and tenth hectemorial lines, having an inter-
val of 16 equinoxial hours, or 240° between the adjacent up-
per apices; the describing diameter completes. its: revolution,
and comes to the point from which it set out at the end of two
circumferences or 720° ; the number of the upper apices being
3, which, multiplied by 240, is equal to 360 x 2; this is seen
in figures 5th and 11th.

The undulated cone which contains the first and eleventh
hectemorial lines, figures 4th and 10th, having an interval of
20 equinoxial hours, or 300° between the upper apices of the.
undulations, the describing diameter must go over five circum-
ferences before it comes to. the point from which it set out, be-
cause 300 multiplied by 6, which is the number of upper api-.
ces, is equal to 360 x. 5..

gi, The

eh ON THE ANTIQUE HOUR-LINES.

The circumstances of each of the undulated cones with re-
spect to the number of undulations and of circumferences, are

as follows :

| The undulated cone containing
hectemortal lines

—$ ———S- ————-

In degrees.

First A, and eleventh IA,| 300
Second B, and tenth 1,| 240
Third T, and ninth @,| 180
Fourth A, and eighth H,| 120
Fifth E, and seventh = Z, 60

o the | intercepts between two
adjacent upper apices,

a

In equinoc-
tial hours.

20°
16
12
8
4

of upper

apices 1s

Awnw a”

—— —— |

The number | The number of

circumferences in
which a revolu.
| tion is completed,
ts,

Hee bo &

Four of the five undulated cones have opposite and similar
undulated cones, formed by the remote half of the generating
diameter; but in that undulated cone which contains the
fourth hectemorial line A, and eighth H, the two opposite un-
dulated cones coincide in one, as is seen in figures 7th and. 13th.

The algebraic formula expres-
ses the different branches of the
right section of the undulated
cone, by the change of sign of
tan. pol. dist. in the values of @
and y;

n :
TS cosgs—cos8)) tan. pol. dist,

y = sin. stan. pol. dist.

For example, in the right sec-
tion of the undulated cone which
contains the third and ninth hec-

temorial

—+-

~
ON THE ANTIQUE HOUR-LINES. | 13

temorial lines, the radii from the centre P’ are = tan. poi. dist.
and the co-ordinates are affected by that quantity. Ifthe gene-
rating diameter GKR move in the direction of the dart, and
set out from I; it describes the curvilinear branch A, and
tan. pol. dist. is positive till the generating diameter come to the
situation II, where it is infinite. If its revolution be continued,
it re-appears at ITI, on the other side ofthe centre with the nega-
tive sign, and gives the curvilinear branch B; at IV. it is again
infinite, and re-appears positive at V, going on to form the curvi-
linear branch C; at VI. it is infinite; and at VII. it becomes
negative, and forms the branch D; it then comes out positive
at I, and goes over its former path. ‘The way that the change
of sign takes place is apparent, by considering that whilst the
diameter is moving in the direction of the dart, it has another
motion at right angles to the plane of projection. Let GPK
be a section of the generating sphere, at right angles to the
plane of projection; NPR being the section of that plane ;
GKR. is the generating diameter; and when in the position
GKR, then tan. pol. dist. = PR, ne is positive ; when GK is:
parallel to PR, then tan. pol. dist. is infinite. If the motion in
this plane be continued, tan. pol. dist. passes to the other side
of P, as at PN, and is affected with the contrary sign.

Most of the writers who have spoken of the hectemorial
lines, have treated them as great circles, because their intertro-
pical parts, at a moderate height of the pole, coincide sensibly
with great circles; and it is. this case with which. authors had
to do in ep a the gnomonic projection of the hectemo-
rial lines for the climates of Greece or of Italy. The writings
of a considerable number of authors on this subject have been
consulted, and they all take the hectemorial lines. for great
circles, except Cravius and Mowrucia. Cxavius demonstrates
that the antique hour-lines do not coincide with great circles;

Vor, VIII. P. 1, kK and:

74 ON THE ANTIQUE HOUR-LINES.

and Monrucra merely states, but without discussion, that they
are curves of a peculiar nature *.

It has been shewn above, chiefly by means of a paced on
a plane touching the sphere at the pole, that the hectemorial
hour-lines on the oblique sphere are not great circles; and be-
cause the describing diameter, in order to form a continuous
and uniform surface, must go on moving during its whole re-
volution with that motion which it had in the beginning of its
course, and must be always included between the two parallels
that touch the horizon, it is concluded that the curved surface

whase

* The passages from Cravius and Montucta are as follows:

Crarix Astrolabium lib. i. lemma 39. “ Circuli maximi transeuntes per horas
inequales A¢quatoris, et duorum paratlelorum oppositorum, non necessario per
horas inzequales parallelorum intermediorum transeunt in sphera obliqua.” He
gives a demonstration of this, and concludes, in the scholium, that in order to de-
lineate the antique hours with strict accuracy, a considerable number of the se-
midiurnal arcs are to be divided into six parts, and the corresponding points of
division joined.

Monrvcra, Hist. des Math. tom i, edition de 1758S: ‘ Les lignes de ces sortes
Wheures {les heures antiques] ne sont point droites comme les precedentes, mais
courbes, et meme d’une forme tres bizarre ; de sorte qu’on ne peut les decrire
qu’en determinant plusieurs points de chaewne; la maniére de les trouver se pre-
sentera facilement a tout geometre ; c’est pourquoi nous ne nous y arretons pas.”

The circumstance mentioned in the beginning of the paragraph to which this
note refers, has led the celebrated and profound astronomer Deramere to con-
trovert the opinion of Monructa in the following words: “ Monrtucta dit, en
parlant des heures temporaires antiques, qu’elles sont courbes, et méme d’une
forme tres bizarre, &c. Hist. des Mathem. tom i. On ne congoit pas com-
ment une pareille inadvertance a pu echapper 4 un homme aussi instruit ; car si
la surface est spherique, ces lignes seront des grands cercles; et si la surface est
plane, elles seront des lignes droites, puisqu’elles seront les intersections des plans
de ces grands cercles avec le plan du cadran.” Detampre sur un cadran“anti-
que trouvé dans Visle de Delos, et par occasion de la gnomonique des anciens ; noz

tice lue & la classe des Sctences Physiques et Mathematiques de [Institut Royal
de France, le 10 Octobre 1814.

ON THE ANTIQUE HOUR-LINES. 15

whose section contains the hectemorial line, isa kind of undu-
lated conical surface; and the right sections of the surface are
two infinite unenclosed bases, one’on each side of the vertex
of the undulated cone. This section, at right angles to the
axis, consists of several bicrural branches, varying in number
as the cone belongs to each different hectemorial line.

Of the Gnomonic Instruments of the Ancients.

The object of the preceding pages has been, to treat of the
eurves to which the hectemorial lines belong. As an appen-
dix, it may not be improper to enumetate some of the remains
of art which contain the antique hour-lines ; for these hour--
lines are the intertropical parts of the hectemorial lines. Se-
i i Saag of these gnomonic instruments exist.

The first to be ‘mentioned, and the most perfect, are the:
eight sun-dials on the Tower of Andronicus Cyrrhestes, at A-
thens. They appear to have been coeval with the building,
and to have formed part of the original design, as may be in-
ferred from the care with which they are'delineated, and from
the greatest part of the surface of the wall being left plane to
receive the lines. This tower’is mentioned under the denomi-
nation of horologium by Varro, who flourished in the 85th
year before the Christian era; it is also spoken of by Virru-
vius. The carefully wrought channels, and cylindrical cavities
in the pavement, and the cylindrical chamber at the south side,
have led to the conjecture, that, béfides serving to shew the:
hour when the sun was shining on it, the tower was formed to.
contain some machine of the nature of the clepsydra, whereby
the hour might be known at all times for the use of the city..
Another of the destinations of this tower was to indicate the

K 2 direction:

76 ON THE ANTIQUE HOUR-LINES:

direction of the wind. Tach of the eight dials is exposed to
one of the eight principal equidistant points of the horizon ;
two of the dials being parallel to the plane of the meridian,
The radii of the spheres from which the dials are projected,
vary ; the smallest being about eight inches, and the greatest
about twenty-five inches. In Sruart’s Antiquities of Athens, the
building and the dials are represented in detail.

The second example of the gnomonic lines of the ancients,
js in the valuable collection of antiquities brought from Athens
by the Earl.of Ereiy. It consists of four vertical dials, two of
which are nearly south-east, and two nearly south-west in azi-
muth. They are inscribed on a block of white marble, which
bears the maker’s name. The radius of the generating sphere
is about four inches and a half.

The third example, is a projection of the antique hour-lines
on the inner surface of a cone whose axis is parallel to the axis
of the earth. It exists at Athens, and is figured by Sruarr.

The fourth is a small east dial, on a vertical plane, described
by DrvaMsre. It was found at Delos. The radius is half an
inch.

The fifth is a piece of Roman workmanship, figured by Bors-
sarp *. It is composed of five dials on the upper part of a
squared block of marble ; three of the vertical sides of which
are covered with an ancient Roman agricultural calendar. In
like manner, the treatise of Paruaprus de Re rustica, which is
a set of agricultural directions for every month, contains a gno-
monic table, shewing the length of a man’s shadow for each
month, and for a climate in Italy.

Some

* Borssarv1 Antiquitates Romane.

ON THE ANTIQUE HOUR-LINES. q7

Some. fragments of ancient dials, are also published by Grx-
wius *.

Except the table of Pariapis, the instruments above men-

_ tioned are each made for an unvarying azimuth. In the de-
scription of the antiquities of Herculaneum +, there is repre-
sented and explained a dial whose azimuth is changeable, to
suit the hour and the different declinations of the sun. It jis
drawn on an irregularly curved surface of bronze, and the de-
clinations are marked with the Roman names of the months.

The ancient names of different kinds of fixed and moveable
sun-dials, with the names of their inventors, are given by Vi-
TRUVIUS.

Something respecting the time of the first introduction of
gnomonic instruments, is to be collected from Greek and Ro-
man authors. The ancient inhabitants of Egypt appear to

have cultivated astronomy at a time prior to the earliest histo-
rical accounts ; and they have left a monument of their practi-
cal skill in that science, in the accurate meridional position of
these most ancient of human works the Pyramids. Portions
of their knowledge were diffused amongst the Hebrews and
Babylonians.

, The astronomical science of the Greeks was derived partly

from the Egyptians, and partly from the Babylonians {. Tua-

Es || acquired his knowledge of astronomy and geometry
from the Egyptian priests, and introduced these sciences into
Greece. The gnomonic projection of the sphere is a branch

of the doctrine of spherical astronomy, and when applied to
the

* Graevu Thesaurus Antiquitatum Romanarum.

+ Le Pitture antiche d’Erculano, tom. iii, Napoli 1762.
+ Heroporvus. >

}| Diogenes Larrtivs.

78: ON THE ANTIQUE HOUR-LINES,

the purpose of shewing the parts of the day, constitutes the
Sun-dial, an instrument which may be supposed to have come:
into use soon after the introduction of astronomy. According
to Driocenes Larrtius and Pury, the first gnomonic instru-

ment that appeared in Greece was constructed by a disciple of

Tuaxes, about the 545th year before the Christian era, and 115
years before the death of Prricres. SaumaisE * contends, that
this instrument was for the use of astronomers only, and that
sun-dials did not come into general use in Greece till 200
years after, that is, a short time before the age of ALEXANpER.

The Romans got their first sun-dial from one of the Greek
cities of Sicily +, 260 years before the Christian era ; and for
nearly a hundred years after, they possessed no artist acquaint-
ed with the principles of the instrument, so as to construct one:
adjusted to the climate of Rome.. 3

* Sapmasi Pliniane Exercitationes;

+ Puinn Hist. Naturalis.

Explanation

‘ON THE ANTIQUE HOUR-LINES. 79

» Explanation of the Figures.

Central Projection of the Twelve Hour-lines, Figure ist do
Figure 3d.

Figure. 1st, Is a central or gnomonic projection of the hecte-
morial lines or antique hour-lines, on the inside of a plane
touching the sphere at the elevated pole of the equator.
This and all the other figures are drawn for the latitude
66° 30. Each antique hour-line is marked with the Greek
numeral that belongs to it,

Figure 2d, Is a central projection of the summer Ne se of these
lines on the inside of a plane touching the apbere at the
depressed pole of the equator.

The circle placed between figure Ist and figure 2d is a
great circle of that sphere from which all the projections
jap these. figures (except figure 9th) are formed.

Figure 3d, Is a central projection of the hectemorial lines on a

.. plane touching the sphere at the depressed intersection of
the meridian and the equator.

yo Be of 1 the five undulated Cones which contain the antique

hour. lines, by a plane at right angles to the avis, figure 4th
‘to figure 8th.

Figure 4th, Is a section at right sie to the axis of the un-
dulated conical surface, which contains the first antique
»hour-line A, and eleventh 1A. In this and the other fi-
gures, the full lines are the section of one of the two op-
posite cones, and the dotted lines are the section of the

other.

50. ON THE ANTIQUE HOUR-LINES.

other. The section of the same undulated cone by a cy-
lindrical surface, is seen in figure 10th.

Figure 5th, Is the right section of the undulated cone whicli
contains the second antique hour-line B, and tenth I. The
section, by a cylindrical surface, is seer at figure 11th.

Figure 6th, Is the right section of the undulated cone which:

ao

* contains the third antique hour-line T, and ninth ©. Its
section, by a cylindrical surface, is figure 12th. A per-
spective and shaded view of this undulated conical sur-
face is figure 9. }

Figure 7th, Is the right section of the undulated cone which:
contains the fourth antique hour-line A, and the eighth H ;,
figure 13th is its section by a cylindrical surface.

Figure 8th, Is the right section of the undulated cone which
contains the fifth antique hour-line E, and the seventh Z..
Figure 14th, is its section by a cylindrical surface.

Perspective and shaded wiew of one of the Surfaces, figure 9th.

Figure 9th, Is a perspective and shaded view of the undulated’
conical surface which contains the third antique hour-line
Tr, and ninth ©; the point of sight is in the plane of the:
equator, and the distance of the eye is two. diameters from.
the centre of the sphere ; in this view only one of the two.
opposite surfaces is drawn. The right section of these
opposite cones is figure 6th, and their section by a cylin-
drical surface is figure 12th.

Sections:

a

NO THE ANTIQUE HOUR-LINES. 81

Sections of the five undulated Conical Surfaces by a Cylindri-
cal Surface, figures 10th to 14th.

Figure 10th, Is the section of the undulated cone which con-
tains the first antique hour-line A, and eleventh IA, by a
cylindrical surface touching the sphere at the equator.
To avoid intricacy in this figure, the section of only one:
of the two opposite cones is drawn.. Figure 4th is the:
right section of the two opposite surfaces..

Figure 11th, Is the section of the undulated cone which con-
tains the second antique hour-line B, and tenth I, by a cy-
lindrical surface. The full line is the section of one of
the two opposite cones; the dotted line is the section
of the other. Fig. 5. is the right section of this surface.

Figure 12th, Is the section of the two opposite surfaces which.
contain the third antique hour-line I, and ninth 0, by a
cylindrical surface. Their right section is figure 6th ; and

one of these two opposite surfaces is represented in per-
spective, and shaded at figure 9th. ee:

Figure 13th, Is the section of the undulated cone which con-
tains the fourth antique hour-line A, and eighth H, by a
cylindrical surface. In this itdutieea cone, the two op-
posite conical surfaces coincide in one: there are therefore
no dotted lines, neither on this figure, nor on figure 7th,
which is the right section of this undulated cone.

Figure 14th, Is the section of the undulated cone which con-
tains the fifth antique hour-line E, and seventh Z, by a cy-
lindrical surface, “Figure 8th, is the right section of the
same.

Vot. VIII. P. I. iy V.

“Wotooe

oh 0 ae

ds. "to, Gating, ih

PLATE I. Engraved for the Royal Society Trans" Vol 8.page 82.

Ze
Oe

- wn

Engraved by WaD tears Edin?

PLATE Il. Engraved. tor the Rapal Society Trans’ Tol b page 82.
Fig. 7

fe Se 7 ee eee
r,@ —*< Se -—— shes 5
ed wK Co ( Le K Ar <"|

Engraved by WA DLguare dial

'
— ~ ~ —

Y. On the Origin of Cremation, or the Burning of the Dead.
By Joun Jamurson, D. D. F. B.S. & F. AS. E,

(Read April 3. 1815.)

S far as we can judge from historical records, the primevat
mode of disposing of dead bodies, was by inhumation.

It has been observed in another essay, that according to Puuyy,
the ancient Romans did not burn their dead, but consigned
them to the earth *, It must be admitted, however, that by
some the mode of cremation had been preferred in a very ear-
ly period of their history ; as we cannot otherwise account for
the prohibition, which Piurarcn ascribes to Numa, as to the
burning of his body. If we may eredit the testimony of Crcz-
Ro, the Greeks, during the reign of Crcrors, inhumated their

dead +. The same mode of interment is attributed, by xian,

to the Athenians |; and by Priurarcu to the Greeks in genes.
ral ||, It is well known that Cecrors and Danaus, who brought
iL 2 colonies

* Pury. Hist. Nat. lib. viii. ¢. 54, _t De. Leg, lib. ii.

+ Var. Hist, lib. v. 14.3 vii. 19, || In Vit. Soroy,

84 ON THE ORIGIN OF CREMATION,

colonies into Athens and Argos, were Egyptians ; and general-
ly admitted that Capmus, who founded Thebes in Beeotia, was a
Phenician. It may therefore be conjectured, that as neither the
Egyptians nor the Phenicians burnt their dead, while the me-
mory of these illustrious men retained any considerable influence,
the colonies planted by them would strictly adhere to the rites
of sepulture which they had introduced ; especially as these
had been sanctioned by the authority and example of their an-
cestors, in the countries from which they had migrated. From
the institutes of Lycurcus it is evident, that, in his time, the
ancient mode of inhumation prevailed among the Spartans.
For he enacted, that the dead should be deposited in the earth,
wrapt in a covering of scarlet cloth, and surrounded with olive
leaves *.

It seems to be generally believed, that, in later ages, the
Greeks universally burned their dead. Lwucran, indeed, as
Porter has remarked in his Archeologia, expressly assigns cre-
mation to Greece, and inhumation to the Persians}. But this
must be understood with great latitude. From the language
ascribed by Prato to Socrates, it appears, that both these
modes had been promiscuously used in his time, according to
the predilection of individuals. For he speaks of it as a mat-
ter of indifference to him, whether, after his death, his body
should be burned or buried. The language of /Zt1an would -
imply, that inhumation had continued to be the general prac-
tice at Athens. For he says, “ It is an Athenian law, that if
“ any one accidentally meet with the corpse of a man not bu-
“* ried, he shall cover it entirely with earth; and that the dead

“ shall

® Prurarcn. in Vit. Lycure.

t Aucrcpesvor ncerce 20yn res Ta Peec, o wiv EAAny, aveey. ade Megons, ebatev, &c. Lucian. de
Luctu, Oper. ii. 306. edit. Amstel. 1687.

OR THE BURNING OF THE DEAD. 85

* shall be buried so that they may look towards the west *.”
Both these institutes obviously preclude the idea of crema-
tion.

But although, in some of the Grecian states, the ancient cus-
tom seems to have long retained its influence, it cannot be de-
nied, that, according to Homer, the mode of burning had been
yery common among the Greeks before the time of the Trojan
war. From the particularity with which he describes the fune-
ral rites of Parroctus, in the twenty-third book of the Jliad,
there is no reason to suppose that he viewed them as even at
that time a recent institution.

It would appear, indeed, that the Phrygians were acquainted
with this custom before it was received by the Greeks +. But
it can scarcely be supposed, that the Greeks borrowed it from
them, either during the Trojan war, or in any preceding era.
It is far more probable, that it had made its way from Thrace,
where it unquestionably prevailed in an early age { ; especial-
ly as it cannot reasonably be doubted, that a considerable, if
not the greatest part of Greece, was peopled from that coun-
try. The Thracians, most probably, received this custom from
their progenitors the Scythians, who inhabited those vast re-

_gions now known by the name of Tartary. As the people of

' that country, apparently in the most remote ages,.erected very
large tumuli in honour of the dead, it is undeniable, from the
remains found in those which have been explored by the Rus-
sians or Tartars, that, in many instances at least, they burned
their bodies. Mr Tooxe, indeed, informs us, that no sepul-
chral urns have been discovered in any of these tombs.

“ Of
* Aun. Var. Hist, lib. v. c. 14.
+ Azex. ab Anexanpro, Gen. Dies, lib. iii. c. 2,

t Heropor. Hist. Terpsicn. c. 8.

86 ON THE ORIGIN OF CREMATION,

“ Of these Russian and Siberian sepulchres, some (he says)
are encompassed with a square wall of large quarry stones,
placed in an erect position; others are covered only with a
small heap of stones, or they are tumuli adorned at top. In
many of these sepulchres the bones of men, and frequently
of horses, are found, and in a condition that renders it pro-
bable the bodies were not burnt before they were inhumed.
Other bones shew clearly that they have been previously
burnt ; because a part of them is unconsumed, and because
they lie in a disordered manner, and some of them are want-
ing. Urns, in which other nations of antiquity have deposi-
ted the ashes of their dead, are never met with here. But
sometimes what remained of the bodies after the combu-
stion, and even whole carcases, are found wrapped up in thin
plates of gold—There is a very remarkable circumstance
observable in some of the tombs on the upper part of the
Yenisei, which forms an exception to the general rule of
other sepulchres. Instead of ornaments and utensils of gold
and silver found in other tombs, you meet here only with
copper utensils, Even such instruments as would have been
better wrought of iron are here found all of copper, as
knives, darts and daggers. The nation, therefore, whose
dead are here inhumed, seems to have been unacquainted
with the use of iron; and these tombs must accordingly be
more ancient than the others *.”

This learned writer seems himself to admit, that some of

these monuments are far more ancient than others; and gives
an indubitable proof of the high antiquity of some of them,
when he remarks, that all the instruments found in them were

made

* Account of the Burial-places of the ancient 'l'artars, by the Reverend Wix-

siam Tooxe, F.R.S. Chaplain to the English Factory at St Petersburgh, Ar-
chaologia, vol, vii. p. 223, 224.

OR THE BURNING OF THE DEAD. 87

made of copper; whence he reasonably concludes, that the use
of iron had been unknown in those regions when these monu-
ments were erected. This might seem to carry us as far back
as to the times of the Massagetz ; who, as we learn from Hr-
Ropotus, used no iron, having all their weapons made of
brass *. From the same venerable historian, we learn the great
respect which the Scythians had for the tombs of their ances-
tors. That intelligent traveller SrranLenzerc informs us, that
these monuments contain earthen urns of different sizes f.
He does not say, however, that bones have been found in any
of them. It affords a strong presumption that many tribes of
the Scythians anciently burned their dead, that the Chinese
Tartars, who are said to be the descendants of those Scythians
whose tombs are to be seen on the river Jenisei, still retain
this mode ft.

Perhaps the first notices which we have of this custom, in
ancient history, occur in the slender accounts that have been
handed down to us concerning the manners of some of the na-
tions of Hindostan. How early they burned their dead we are
not informed. But we certainly know, that, before the time of
Axexanver of Macedon, they erected funeral piles for the li-
ving. Quintus Curtius, from Troeus, asserts, that those who
were called Wise Men, when they saw the infirmities of age
_ approaching, ordered their pyres to be raised, and cheerfully
devoted themselves to the flames §. The same thing is assert-
ed by Ciemens of Alexandria concerning the Gymnosophists.

Speaking

"Ove piv yap & ctingecs nae) dedeis nde cooydeuis, ywrnol rec medvree xeewvras. Clio, c. 215.
4p Description of the North and East parts of Europe and Asia, p. 364, 365,

t Ibid. p. 365. 367. § Hist. lib. viii.

88 ON THE ORIGIN OF CREMATION,

Speaking of those who unnecessarily exposed themselves to de-
struction, under the false idea of being martyrs, he adds, ‘ In
« vain do they give themselves up to death, as the Gymnoso-
phists of India rashly cast themselves into the flames *.

As it is acknowledged even by heathen writers, that the
most ancient mode was that of inhumation, a question natural-
ly occurs, which, although from deficiency of evidence it may
be impossible to solve in a satisfactory manner, affords ample
ground for curious and interesting disquisition. It is this ;
Whence might the practice of cremation originate ? or, in other
words, What could induce men, in opposition to the feelings of
nature, to devote the mortal part of this frame, which they
had cherished so tenderly during life, as far as possible to appa-
rent destruction, after the departure of the spirit ?

By the primitive Christians it was objected to cremation,
that the practice involved in it the idea of inhumanity to the
body. Hence Terruriian having remarked, that some of the
gentiles disapproved of the mode of burning, because they
wached to spare the soul, which hovered over the body after
death, subjoins, “ But we have another reason,—that of piety,
“ not as flattering the reliques of the soul, but as detesting
* cruelty even to the body; because, being itself man, it does
* not deserve. to be subjected to a penal death f.” In another

. place,

* Cuvara dt taurde drod:doace neva, noibdmreg xxi or Tay LddY yrpevorePiscel porrecies mugl. emt) 02
Si Yevdaryeos ore TH capex Oiabwcrrect, &c. Crem. ALEXANDR. Strom. lib. iv. p. 351. edit.
Lugd. 1616.

+ Et hoc enim in opinione quorundam est ; propterea nec ignibus funerandum
aiunt, parcentes superfluo anim. Alia est autem ratio pietatis istius, non reli-
quiis anime adulatrix, sed crudelitatis etiam corporis nomine aversatrix, quod et
ipsum homo non utique mereatur poenali exitu impendi. Trrtuxnuian. de Anim.
c. 5k.

OR THE BURNING OF THE DEAD. 89

place, he ridicules the heathen for their inconsistency, in first
burning the dead in the most unfeeling manner, and then cele-
brating the feasts which they denominated Parentalia, by the
same fires both honouring and insulting them, treating them as
if they had been gluttons after they had consumed them. “ O
“ piety !” he exclaims, “ sporting itself in acts of cruelty *.”

The adversaries of the Christians, indeed, objected to them,
that they had a weightier reason for opposing cremation. M1-
nucius Fenix, accordingly, introduces the heathen as saying,
“ For this reason they execrate the funeral pile, and condemn
“ sepulture by burning,” as if it precluded the possibility of re-
surrection. But Mrvuctus replies, “ We do not, as you be-
“ lieve, fear any injury by this kind of sepulture; but we ad-
“here to inhumation as the more ancient and the preferable
“mode +.”

From the ridiculous reason assigned by Terrutiian, for the
reluctance which some of the heathen felt to cremation, it ap-
pears fMat they were actuated by the self-same feeling with
Christians ; although, according to this ancient writer, they
transferred their compassion from the body to the soul. But
some of them, it is evident, viewed the practice as inhuman on

Vox. VIII. P. I. M a

* Ego magis ridebo vulgus, tunc quoque quum ipsos defunctos atrocissime
exurit, quos postmodum gulosissime nutrit, iisdem ignibus et promerens et of-
fendens. O pietatem de crudelitate ludentem! Id. de Resurrect. c. i.

+ Inde videlicet et execrantur rogos, et damnant ignium sepulturas, quasi non
omne corpus, etsi flammis subtrahatur, annis tamen et etatibus in terram resol-
vatur.—Hoc errore decepti beatam sibi, ut bonis, et perpetem vitam mortuis pol-
licentur ; czteris, ut injustis, peenam sempiternam. Mun. Feu. Octavius, p. 97,
98. edit. Lugd. 1672. Nec, ut creditis, ullum damnum sepulture timemus, sed
veterem, et meliorem consuetudinem humandi frequentamus. Ibid. p. 327, 328.

90 ON THE ORIGIN OF CREMATION,

a more general ground. Hence a poet, cited by Eusrarutvus,
introduces a person as exclaiming against it, and as invoking
Prometuevs to hasten to his assistance, and snatch, if possible,
from mortals, the fire with which he had supplied them *.

As Jews and Christians, in every age, preferred inhumation,
because it bore a more direct analogy to the origin of man, it
is remarkable, that even Lucretius virtually assigns the same
reason for the practice :

Cedit enim retro, de terra quod fuit ante
In terram.

A variety of reasons may be supposed, either separately or
in connection with each other, according to the prejudices and
habits of particular tribes or families, to have induced the in-
troduction of this mode. The influence of such reasons may
also be supposed to have been greater or less, in proportion to
their relative probability, as they appeared to the minds of
those who contemplated them ; or according to peculiar cir-
cumstances, as existing in different ages, or among different
nations. There are other reasons, which have a superior claim
to our attention, as being expressly mentioned by ancient wri-
ters.

1. The mode of cremation may have been preferred, in some
instances, as a means of guarding the living against the fatal
effects of putridity from the dead. The Romans, we know,
originally used their dwelling-houses as tombs for their decea-
sed relations. The same practice prevailed among the more
early Greeks +. The Thebans, in one period of their history,

had

* Evsraru. in Iliad. A. p. 32.

- Pare ts ' EY , 5 e
t OF DE ced beeivwy medrspos duct xcceh Woemroy ty ay dixie vods emobavovras ; Hyutis 3: cobray gdiy

xoicvusy. Pua, Minoe, Oper. ii. p. 315. edit. Paris. 1578.

OR THE BURNING OF THE DEAD. 91

had a law, that no one should build a house without providing
a repository for his dead*. The disastrous consequences of
this unnatural approximation, as they were strangers to the art
of embalming, might be felt for a considerable time, before in-
dividuals could find it possible to release themselves from the
fetters of custom, strengthened by superstition. But as men
advanced in civilization, this strange practice would become
matter of cognisance to those whose office obliged them to
watch over the public weal; and we may naturally enough
suppose, that the prohibition of domestic sepulture would be
an intermediate step between the observation of this custom,
and the enactment of that law which forbade the Romans ei-
ther to bury, or to burn, the bodies of the dead within the city.
It may be observed by the way, indeed, that they, with many
other ancient nations, as well as the Chinese, have manifested

much more common sense and delicacy in -this respect than
the nations of modern Europe, notwithstanding their boasted
refinement.

2. Those who wished to preserve the remains of the dead as
long as possible, in token of regard for their memory, might
prefer this mode to inhumation. Knowing that, in conse-
quence of interment in the common way, the bones themselves
gradually moulder into dust, till every vestige of the person be
lost, they might in some instances adopt the plan of calcina-
tion, as a means of partially preserving them. There can be no
doubt that this was the most eligible mode, where embalming
was not used, when it was meant to transport the remains of the
dead from one place to another. As the Greeks ascribe the

- introduction of cremation 'to Hercurss, they in effect assign, as
the reason of his burning the body of Arerus, that he was un-
M2 der

* * V. Porrer’s Archeol. ii. p, 218. Lond. edit. 1751.

92 ON. THE ORIGIN OF CREMATION,

der the necessity of transmitting it to his father Licymntus, as
the only way in which he could fulfil the promise he had made
to restore his son.

3. Before cremation was generally adopted by any nation, it
might be found necessary during the prevalence of any pesti-
lential disease. In the passage in which Homer first mentions
this mode as observed by the Greeks, although he does not di-
rectly assign the pestilence as the reason of its being used, he
ascribes the frequency of the kindling of the funeral pile to the
prevalence of that contagion which was viewed as the effect of
the wrath of AroLto :

\ ~ / Vv 7 A
Avra exer’ auroios Peros eyerevnes eQueis,
, 7 / v4.
Baan csci de rvent vexvar xasovro Oawesces.
Iliad. A. 51.

From a comparison of this passage, indeed, with what the
poet has said in his introduction, it may be inferred, that cre-
mation was supposed to be more peculiarly necessary in this
ease ; as he there speaks of the multitude of heroes that fell in
battle, who were left a prey to dogs and to all the fowls of
heaven :

c ~ /
"Auras De choose revye nuverow,

> ~ vA ~
Otwvoici re THC.

It appears that the Hebrews, though they adhered to the
more ancient mode, had no objection to burn the dead in a
time of contagion. In this sense are we to understand the
language of the prophet Amos, when foretelling the conse-
quences of a continued famine: “ A man’s uncle,” or near re-
lation, “ shall take him up, and he that burneth him, to bring

“ out

OR THE BURNING OF THE DEAD. 93

“ out the bones out of the house, and shall say unto him that
“ is by the sides of the house, Is there yet any with thee * ?”
Though they carried the bones to the sepulchres, they did not
venture to bring out the dead body before cremation, lest others
should be infected.
From several passages in the Sacred Writings, it has been in-
ferred, that the Jews in a later age actually burnt their dead.
But it is to be observed, that as the language refers exclusive-
ly to their kings, it is not said that they burnt their bodies, but
only that they “ made burnings for them +.” Even from the
account which is given of the honours paid to the memory of
Asa, though it has been urged as a proof that the Jews had
adopted cremation, it is evident that the burning was a cere-
mony superadded to his interment; for it would appear that
his body was wrapped in spices: “ They buried him in his
* own sepulchre, which he had made for himself in the city of
~“ David, and laid him in the bed,” the coffin or sarcophagus,

as would seem, “ which was filled with sweet odours and di-
. © vers kinds of spices prepared by the apothecaries art; and
“ they made a very great burning for him {.” The writers of
the Ancient Universal History suppose, that these spices were
burnt around the body §. But this does not seem likely; for
we cannot well conceive, how, in this case, the body itself
should not have been affected by the force of the fire. It may,
therefore, more naturally be supposed, that this burning did
not take place in the sepulchre. Perhaps, though the Jews did
not consume the body, yet on such occasions they so far com-

‘ ; plied

* Amos, vi. 10. + 2 Chron. xxi. 19.; Jer, xxxiv, 5.

+ 2 Chron, xvi. 14. § Vol. iii. p. 173.

94 ON THE ORIGIN OF CREMATION,

plied with the customs of other nations, as to erect a funeral
pile at the entrance of the tomb, which they might burn in ho-
nour of the dead, containing nothing save spices and odorife-
rous woods, or having an image of the deceased prince substi-
tuted for the body. It cannot reasonably be thought,’ that
they would have accounted that an honour to their kings,
which was deemed a disgrace to every other person. Not on-
ly in the more early period of their history *, but even towards
the dissolution of the monarchy, the burning of the dead body was
viewed as a sort of posthumous punishment, expressive of the
greatest contempt and detestation. For Josran, we are in-
formed, “ burned the bones of the priests of Baat upon their
“ altars f.”

4. It tended greatly to facilitate the reception of this custom,
that it seemed the most certain plan for protecting the dead
body from those indignities to which it might otherwise have
been subjected. It is highly probable, indeed, that the danger
to which the bodies of departed relations was exposed, of be-
ing disfigured or devoured by beasts of prey, first suggest-
ed the idea of covering their graves with heaps of stones; and
that this course had been followed in a very early stage of so-
ciety. But when war had begun to extend its cruel ravages,
when man had become as unfeeling to his fellows as the tyger
or the hyzena, when his ferocity reached even beyond the hal-
lowed precincts of the tomb; it would be found necessary
to devise some more effectual plan for securing rest to the
dead.

It has been observed, accordingly, in another dissertation,
that, as Priny informs us, the Romans adopted cremation in
consequence of being engaged in distant wars; and also, that

SYLLA,

* Josu, vii, 25. + 2 Chron. xxxiv. 5.

OR THE BURNING OF THE DEAD. 95

Syxxa, contrary to the custom which had hitherto been religi-
ously observed in the Cornelian family, ordered his body to be
committed to the flames, lest the dishonour done by him to
Mantvus might be retaliated. For a similar reason, undoubted-
ly, the valiant inhabitants of Jabesh-gilead “ arose, and went
“ all night, and took the body of Savr, and the bodies of his
* sons, from the wall of Beth-shan, and came to Jabesh and
“ burnt them there *.” They deeply felt the dishonour that
had been already done to their deceased sovereign and his gal-
lant sons, whose bodies had been “ fastened to the wall of
“ Beth-shan,” one of the cities of the Philistines, that they
might be exposed to every species of outrage from their re-
morseless adversaries. ‘They, therefore, carried them off and
burned them ; not with the intention of giving them the fune-
ral honours of cremation, but merely to prevent the possibility
of their being hung up as before. This, they had every reason
to suspect, would have been the case, had they interred them
in the usual way, because the land of Palestine was at this time
completely under the power of their enemies, and circumstan-
ces did not permit them to carry the bodies across Jordan.
They gave them, as far as possible, the common rites of se-
pulture, by interring their remains; but not till they had done
what seemed previously necessary for guarding against a repe-
tition of similar indignities.

_5. Some of the ancients preferred this mode, because, accord-
ing to their ideas (whether well or ill founded, it is not our bu-
siness here to inquire), it most speedily reduced the body to its
first principles. Tuatzs, and his followers, viewed water as
the origin of all things ; and therefore reckoned it most fit that
the body should, by putrefaction, be reduced to its original ele-
ment. _ Hirron, as we learn from Trertuuian, taught the same

doctrine.

* 1 Sam. xxxi. 10,—13.

96 ON THE ORIGIN OF CREMATION,

doctrine *. Heracuirus, who is said to have flourished in the
time of Darius Hysraspes, held fire to be the first principle.
Hence he, with those of his sect, preferred cremation ¢. Ma-
cRoRIUS mentions two of this name, whose doctrine was mate-
rially the same. Heracurrus of Pontus, he says, affirmed that
the soul was light ; and Heracrirus the natural philosopher,
that it was the scintillation of a stellar essence {. “ The old
“ heroes in Homer,” says Sir Tuomas Brown, “ dreaded no-
“ thing more than water or drowning; probably upon the old
“ opinion of the fiery substance of the soul, onely extinguish-
“ able by that element ; and therefore the poet emphatically
“ implieth the total destruction in this kinde of death, which
“ happened to Asax Ortzus |.” Hence Servius, in reference
to the horror expressed by AZNEas in prospect of being ship-
wrecked, remarks, that this was not from the fear of death, but
from the apprehension that his soul might perish, if his body

should have no other than a watery grave §.
Several ancient writers held fire in such estimation, that
they considered it as animated, and therefore as not to be ex-
tinguished

* Terruxuian. de Anima, c. 4.

4+ Vide Avex. ab Aurxanpro Genial. Dies, lib. iii. c. 2. Porrer’s Archeol.
ii. p. 207.

+ Heracuitus Ponticus lucem; Heracritus physicus, scintillam stellaris es-
sentiz. In Somn. Scipion. lib. i.

|| Hydvotaphia, p. 4.

§ Commenting on these words in the first book of the Bneid,

Extemplo Atnex solvuntur frigore membra,
Ingemit, &c.——he says,

Non propter mortem, sequitur enim, O terque quaterque beat, sed propter mortis
genus. Grave est enim secundum Homerum, perire naufragio, quia anima ig-
nea est: et extingui videtur in mari, id est, elemento contrario.

OR THE BURNING OF THE DEAD. 97

tinguished *. Barruoiie has observed, that the ancient
Scandinavians were influenced by a similar idea, how much so-
ever it is enveloped in the darkness of their mythology. As
they believed the principal heaven to be fiery, they adored that
sacred fire which it was impious to extinguish. Fire being
also considered as eternal, they assured themselves that the
soul, which was loosed from the body: by means of this ho-
noured element, would most certainly, and in the most expe-
ditious mode, be conveyed to the seats of the blessed. As
Oonrn had enjoined cremation on his followers, they were per-
suaded that the honour, with which the person whose body was
burned would be received into heaven, would be exactly in the
ratio of the height to which the flame of his funeral pile as-
cended. As they denominated the rainbow “ the bridge of
“ the gods,” by which it was necessary that men should as-
cend. into the celestial regions, they affirmed that the red divi-
sion consisted of fire f. .

This learned writer gives it as his opinion, that Op1x, whom
the northern nations worshipped, was the Sun; that the souls
of heroes were said to be received by him, because they belie-
ved that the soul, being of an igneous essence, was a particle
derived from their deity ; and that the warrior, who led the
Ase, or Asiatic chiefs into Scandinavia, assumed this name, by
which the sun was known in eastern regions, that he might en-
sure divine honours to himself. He thinks that it was with
this design that he ordered his body to be burned, that his sub-
jects, following his example, might be supposed, after death, to
be translated by fire to a state of eternal fellowship with the
object of their adoration.

Vou. VIII. P. I. N 6. The

* V. Scaccuir Myrothecium, lib. i. c. 9. p. 46.
s+ V. Bartuonw. de Causis Contempt.Mort. p. 272,—274.

98 ON THE ORIGIN OF CREMATION,

6. The reception of this mode has been also ascribed to the
influence of the ancient tradition, that the world should be de-
stroyed by means of fire. The very ingenious and learned
physician quoted above, observes, in that light and rather af-
fected sort of style which characterizes his writings ; ‘ Such as
“ by tradition or rational conjecture held any hint of the final
“ pyre of all things, or that this element must at least be too
“ hard for all the rest, might conceive most naturally of the
“ fiery dissolution *.” y

That this tradition was not only known to some of the Greek
philosophers, but even received by some of them, is unques-
tionable. Pxaro, when giving an account of the conference
which Soron had with the Egyptian priests at Sais, acknow-
ledges that they spoke in the most contemptuous terms of the
learning of the Greeks, asserting that they were always chil-
dren, that there was no old man among them, as they still pos-
sessed juvenile minds. ‘“ For, (said one of the senior priests,)
“* you have no ancient doctrine from old tradition, nor any dis-
cipline that has become hoary with age :” adding, “ The
greatest dissolutions of the world have originated, and will
“ originate, from fire and water }.” Soton having proposed
some queries in regard to Dreucation, Pyrrua, Puarron, &c.
the priest proceeded to describe the dissolution by fire, in re-
ference to the mythological account of Puarron having set the
world on fire. “ This (he said) has indeed the air of a fable;
“ but the truth is, there shall be a great parallax,” or “ change,
“ in heaven and in earth; and in a short time the dissolution
“ of terrestrial things shall be effected by much fire }.”

ce

‘49

This
* Brown’s Hydriotaphia, p. 3.
t Thorac! 32 xcerce morre& Qbogce) yeysvariy avdewmoy, xoul erovrecs, wuel pty OF Oder mlyicote
gus fy’ e 2 ee peey’
Trmzus, Oper. iii. p. 22.
$ Taro ptdov ptr oryinun exov Aeyerces, ToD dArndis ist, civ oregi yity xeel Kove’ ovgeevoy fovray me
2chrwksc, noel Dice moaned Hedvay ryivopeeyn Fav Ems vis wuel moras Pdopd Ibid.

pus

OR THE BURNING OF THE DEAD. 99

This, it has been observed, was the general doctrine of the
Platonists. It was also held by other philosophers, especially
by the Stoics. It has been asserted by the learned Grortus,
that Zeno of Cittium, the founder of the sect of the Stoics, re-
ceived this opinion from the Phenicians ; as Cittium was a Phe-
nician colony in Cyprus. Whether this remark be well found-
ed or not, the doctrine was generally adopted by his followers.
Seneca expressly asserts, that, as “ the world had its origin by
“ water, it shall be destroyed by fire*.” He says in another
place ; “ All things shall fall by their own power ; the stars shall
“ rush on the stars, and universal matter shall blaze in one
“ fire. Whatever now shines in the world shall then be in
“ flames +.”

Diocenes Larrtius thus expresses the doctrine of Heracui-
tus; “ There is one world, which was produced by fire, and
“ shall be again reduced into fire t.” Need I add the well-
known language of Ovip ?

Esse quoque in fatis reminiscitur, affore tempus
Quo mare, quo tellus, correptaque regia cceli
_* Ardeat; et mundi moles operosa laboret.
yr , ; Metam. lib. i. ver. 256.

-

It ought to be observed, however, that neither this, nor the
preceding reason, assigned for the introduction of cremation,

_ can be viewed as satisfactory. For it appears that this custom
oF cca . N 2 "was

Lamy gts ‘ t
bs Ita ignis exitus mundi est, humor primordium, Natural. Quest. lib. iii.
ec. 13.

+ Epist. de Consolat. ad Porys.

T “Evee civees xdopeoy, yeneiobas re dutoy & mens, xal mart exmuezctar. WV. Gain’s Court of

the Gentiles, b. iii, c. 7.

100 ON THE ORIGIN OF CREMATION,

was pretty general in Greece before the existence either of
Tuazes or of Heractirus, and, indeed, before either of their
peculiar systems had been broached. It seems highly probable,
indeed, from what Homer has said in regard to. the fate of
Agax, that tl ose philosophers who honoured fire as the prima-
ry element, had built their hypothesis on ancient tradition,

Besides, it is attested by universal experience, that the theo-
ries of philosophers have had very little influence on the man-
ners and customs of mankind. In many instances they have
endeavoured, in their own way, to account for certain customs
which prevailed among their countrymen, or in other nations ;
and have occasionally accommodated their systems to those
modes which had the sanction of antiquity. But it may well be
questioned, if, in any one instance, the dogma of the most cele-
brated school has given rise to a rite or custom which has been
generally received by the multitude. The influence of their
authority was almost entirely confined to their own disciples ;
and, while a theory directly opposite was keenly supported by
others, who claimed equal authority, and who had an equal
right to exhibit this claim, the surrounding multitude could
only stare at the supposed wisdom of contending sects, without
attempting to decide the controversy, or even supposing that
they were qualified for so arduous a task.

We must inquire, therefore, if there was no idea pretty g ge-
nerally received among men, that entwined itself with their re-.
ligious creed, and derived peculiar influence from their hopes _
and fears, as to a state of future existence ; which, if it did not
absolutely originate this custom, must have greatly facilitated
its progress. We accordingly observe,

7. That the body was believed to be unclean after the depar-
ture of the soul; and that it was therefore deemed necessary
that it should be purified by fire. This is given by Eustarutvs

as

OR THE BURNING OF THE DEAD. 101

as one reason for the general reception of this custom in
Greece. ‘ There was,” he says, “ a certain purification by the
“* consumption of fire, because fire is a purificator; wherefore
“ purifications were made by fire.” And Evuripines gives a si-
milar statement, when he says, “ that the body of CrvremMnes-
“« pra was purified,” literally, ‘« sanctified by fire*.” The idea
of pollution by the dead seems to have been early diffused :
and this idea presupposes that of the body, as separated from
the soul, being itself unclean.

_ “ Not the Jews only,” says the accurate and learned Por-
TER, “ but the greatest part of the heathen world, thought
“« themselves polluted by the contact of a dead body ; death
“‘ being contrary to nature, and therefore abhorr’d by every
“ thing endued with life .” Among the Greeks, as long as
there was a corpse in any house, a vessel of water was placed
before the door, that those who had had any communication
with the dead body, might, before their departure, purify them-
selves by washing. Hence Evuririprs makes the chorus call in
question the death of AucrsteEs, because this customary signal
was not exhibited.

TlvAwv ragoiber 0 ovy’ oga

TInydésov, we vomiCerat

Te, yzenS ai xecbvea avrous:
Alcestid, vers. 69.

aa

_' They supposed that even the house in which the corpse lay
‘was not free from pollution. The same poet therefore intro-’
pit uae} ¥. xy :
4a duces
* Aynops 08 rig Hv H Dict wvgos Damedyn TOU vengabevros. art xul To wie cyvisixoy dio xcel ot xee-
decgpess Dice mugs eywovro. soe Eveimidns 92 tosovroy 7 exPavor, are ov Qnow ove To 745 Kavranmmrens
Dinas, wes xeelnynsat Kustatu. in Iliad, A. ver. 52.

+ Archeolog. ii. p. 188.

102 ON THE ORIGIN OF CREMATION,

duces Hexen as saying, “ Our houses are pure, not being defi-
“ Jed by the death of Menetaus*.” To this idea, of defile-
ment being contracted by approximation to the dead, we ought
undoubtedly to trace the custom which prevailed among the
Romans, of thrice sprinkling with consecrated water all the re-
lations of the deceased, and all who had attended the funeral ;
who were then said to have received expiation or lustration.
This ceremony was performed by a priest, after the burnt bones
had been put into an urn, and immediately before he gave the
company leave to depart, by pronouncing the words of vale-
diction.

Ossaque lecta cado texit Chorinzus aheno :
Idem ter socios pura circumtulit unda,
Spargens rore levi, et ramo felicis olive,
Lustravitque viros, dixitque novissima verba.
Vira. En. lib. vi.

As a further purification, those who had attended the obse-
quies of the dead, after being sprinkled with water, as we learn
from Festus, stepped over a fire. This act was called Suffitus.
The house was also purified, and swept with a particular kind
of besom. The Ferie Denicales were certain ceremonies insti-
tuted with this design. The Flamen of Juprrer was laid under
the same restrictions as the Jewish High-priest. He was not
permitted to touch the dead, or even to approach a grave f.
The ancient Scythians themselves, though strangers to any
species of refinement, supposed that they necessarily contract-
ed defilement from the dead. Herovorus relates according-

ly,
Evriewm. Helen. vers. 1446.

+ Aut. Gewn. Noct. Attic. lib. x. c. 15.

OR THE BURNING OF THE DEAD. 103

ly, that they purified themselves, first by washing their heads,
and then by burning hemp-seed on red-hot stones, with which
they produced a powerful fumigation *.

It is well known that the Romans viewed fire and water as
the two great principles of purification, and that with this de-
sign they applied them to things of every description. Hence
Ovip, when describing the Palilia ;

ew,
Certe ego transilui positas ter in ordine flammas ;
Virgaque roratas laurea dedit aquas.

Fast. lib. iv. v. 727.

They extended the purifying virtue of fire not only to their
flocks, but to the owners of them.

—Per flammas saluisse pecus, saluisse colonos.
Ibid. v. 805.

He proceeds to enumerate the different theories which had
been formed, in order to account for the use of fire and water
with this view. The variety of these, he says, caused hesita-
tion as to the real origin. By some it was supposed, that as.
fire purified every thing, particularly metallic substances, it
would have the same effect on the shepherd and his flock.

Omnia purgat edax ignis, vitiumque metallis
Excoquit. Idcirco cum duce purgat oves.
Ibid. v. 785.
ting |
~~ Others imagined, that as all things had their origin from fire
and water, their ancestors had conjoined these elements in their
rites of purification; while there were some who traced this
practice to a conviction that in these existed the principle of
life.

* Melpom. c, 73. 75.

104 ON THE ORIGIN OF CREMATION,

life. Others again, he says, understood the one rite as refer-
ring to Puarrton, and the other to the flood of Deucatron.

Sunt quia Phaéthonta referri
Credant, et nimias Deucalionis aquas.
Ibid. v. 793.

Pieris, in his Heroglyphica, quotes the language of PLav-
tus, as affording a “a that the ancient apie ascribed a
purifying virtue to fire.

Quid impurate, quanquam Volcano studes,
Coenz ne causa, aut mercedis gratia,
Nos nostras edes postulas comburere ?
Aulular. ap Pier, fol. 343. E.

Priertus, however, remarks, that they made a distinction be-
tween the use of fire and water, viewing the one as the means
of purification, the other of expiation. Ignis autem, ut nostri
veteres tradidere, purgat ; aqua expiat, lustratque.

As both these modes of purification were practised long be-
fore the Romans had a national existence, it is not surprising
that the ritual poet found himself quite at a loss to account for
their origin. Though I do not pretend to determine from
whom the Romans received these rites; yet the analogy, not
only in the use, but in the conjunction of these, with that ordi-
nance given to the Hebrews, with respect to the spoils taken
in war, is too striking to be passed over in silence: “ The gold
“ and the silver, the brass, the iron, the tin and the lead, eve-
“ ry thing that may abide the fire, ye shall make it go through
“ the fire, and it shall be clean ; nevertheless, it shall be puri-
“* fied with the water of separation: and all that abideth not

“the

OR THE BURNING OF THE DEAD. 105

* the fire, ye shall make go through the water*.” In the re-
moval of defilement by the dead, the use both of fire and of
water was necessary. A red heifer was to be killed, and com-
pletely burnt without the camp ; the ashes of which were to be
carefully collected, and laid up for future use in regard to all
who had “ touched a dead body, or a bone of a man, ora
“ grave.” The law, enjoining the necessary purification, is
thus expressed): “ For an unclean person,” that is, one pollu-
ted by the dead, “ they shall take of the ashes of the burnt hei-
“ fer of purification,” or of atonement for sin, “jand running wa-
“ ter shall be put thereto in a vessel: and a clean person,” a
priest, according to the Targum of Jonaruan, “ shall take hys-
“sop, and dip it in the water, and sprinkle it upon the tent,
< ‘and upon all the vessels, and upon the persons that were
“ there, and upon him that touched a bone, or one slain, or
“one dead, or a grave: and the clean person shall sprinkle
“ upon the unclean on the third day, and on the seventh day :
Ss and on the seventh day he shall purify himself, and wash his

“ clothes, and bathe himself in water, and shall be clean at
even +.” Prerrus, as we have seen, while he marks the de-
signed distinction between the use of fire and that of water,
says that the fire was viewed as purifying, the water as possess-
ing the power of expiation. This, however, was reversed
among the Hebrews. The ashes of the burnt heifer seem to
have respected the expiation of guilt, and the running water
the removal of pollution. Not only in the Hebrew, but in the
a ritual, sprinkling was expressly enjoined. According
to both, it was administered by similar means. In the one
case, a branch of olive, the emblem of peace and reconciliation,

was used instead of a bunch of hyssop in the other.
Von. VIII. P. I. O It

* Num, xxxi. 22, 23, + Num, xix. 1,—19,

106 ON THE ORIGIN OF CREMATION, ~

It is well known, that, among some of the ancient nations of
the East, parents were wont to consecrate their children to Mo-
loch, whom some suppose to be the Sun, and others Saturn,
by actually giving them up to the devouring flame. The infa-
tuated parents persuaded themselves, that by this inhuman act
they would secure their own prosperity, and that of the rest of
their offspring. But this was not the only mode of consecra-
tion. We learn from Marmonies, that, a great fire being
kindled, the parent delivered his son to the priest, who had the
charge of this fire ; and that he gave him back to the father, in
token of his being permitted to make him pass through the
fire. After this ceremony, the father himself led his child
through the flames, from one side of the fire to the other *.
Correspondent with this account, the language containing the
prohibition of this crime, in Deut. xviii. 10. is rendered in the
Septuagint, “‘ There shall not be found among you any one
“ that purifieth his son or his daughter in fire f.”

The Druids, we are told, on May-eve kindled two great fires,
between which the men and beasts, which were to be sacrificed,
were made to pass in order to their purification t. In Ireland
to this day, at the Feast of Beltein, which is held at the sum-
mer solstice, as they kindle fires on the tops of hills, every
member of a family is made to pass through the fire; this ce-
remony being deemed necessary to ensure good fortune through

the

*® Marmon. de Idololat. c. 6. s. 3.
T Megicabarigay cov inoy ewes val thy Ovyarion dure uel.

{ ‘© Two fires were kindled by (near) one another, on May-eve, in every vil-
lage of the nation, (as well thro’out all Gaule, as in Britain, Ireland, and the ad-
joining lesser islands,) between which fires the men and the beasts to be sacri-
fic'd were to pass.” Totanp’s Hist. of the Druids, Lett. ii. § 4.

OR THE BURNING OF THE DEAD. 107

the succeeding year *. As the designation of this feast retains
the name of Baal or Bel, I need scarcely remark the striking
resemblance of this rite to the ancient worship of the false god
who was thus denominated by the nations of the Kast. There
is great reason, indeed, to believe, that Baal and Moloch were
merely different names for the same idol; the one word signi-
_ fying Lord, and the other King. For those, who in one place
are said to have “ built the high places of Baal,—to cause their
* sons and their daughters to pass through the fire unto Mo-
-“ loch f,” are said, in another, to have “ built the high
“ places of Baal, to burn their sons with fire for burnt offer-
s ings unto Baal}.” There can be no doubt that the wor-

9 of Baal was that of the sun, who was designed “ the lord,”
and « the king, of heaven.”

The ancient Goths ascribed a similar virtue to this element.
When, in their religious feasts, they drunk in honour of their
ods or departed heroes, they stood around a great fire in the
st of the temple, and caused the cups, filled with wine or

~ mead, to ) be passed through gpe: flames ||.

v6 PENNANT ane notice of a singular superstition, which still
remains in the Highlands of Scotland, and which must certain-
ly be viewed as a remnant of druidical worship. “ It has hap-
Sf ‘ pened,” he, ys, “ iehigts after baptism, the father has placed
si om O 2 “ao

Me a Thus I Tae seen the people running and leaping through the St John’s
fires in Ireland; and not only proud of passing unsing’d, but, as if it were some
be lustration, thinking themselves in a special manner blest by this ceremo-
‘ny, of whose original, nevertheless, they were wholly ignorant, in their imperfect
imitation of it.” Toxanp, ibid. § 7. V. also Borxass’s Antiquities of Corn-
wall, p. 130.

if Jer. xxxii. 35. { Jer. xix. 5,

|| Sturteson, Vit. Haquin. Adalstan. V. Keysuen. Antiq. Septentr. p. 355,
356.

108 ON THE ORIGIN OF CREMATION,

al

‘ a basket, filled with bread and cheese, on the pot-hook that
“ impended over the fire in the middle of the room, which the
“ company sit around, and the child is thrice handed across.
“ the fire, with the design to frustrate all attempts of evil spi-
“ rits, or evil eyes. This,” he adds, “ originally seems to have
“ been designed as a purification, and of idolatrous origin, as.
“ the Jeradlites made their children to pass through the fire to.
“ Moloch *.”

The mode of performing this unhallowed rite is didfexenggd in
some parts of the Highlands. One holds the new-born child
by the shoulders, and another by the feet, while they shove it
backwards and forwards across the fire. This is sometimes
used as a test, whether the child be of the right blood, or mere-
ly a fairy urchin substituted in lieu of the genuine offspring.
If, after this operation, the child, on being put to bed, fall into.
a copious perspiration, it is viewed as an infallible proof that
there has been no elvish imposition. It must be admitted, in-
deed, that scarcely any method could be adopted more likely
to ensure the wished for favourable omen. It may be obser-
ved, that, in the investigation of ancient superstitions, we have
many examples of a change of the reason assigned for a pecu-
liar rite, especially if there has been a change of the religious.
ereed of'a people; when there is no ground to doubt that the
rite itself has remained unaltered. m

I have met with one superstition in the low country, (for it
still exists in the county of Angus), which seems to claim the
same origin. A burning coal is put into the water in which. a
new-born child is to be erates Were this important ceremo-
ny neglected, it is believed by many that the infant could not
thrive.

The

* Tour in Scotland, 1772, p. 46:

OR THE BURNING OF THE DEAD. 109

The language of Vireit proves, that the Romans were not
strangers to the same kind of idolatry. As the mountain So-
racte was consecrated to AroLto, his votaries manifested their
ardour in his service, by rushing through the burning coals of
the fire lighted up in honour of their god. ©

Summe deum, sancti custos Soractis Apolla,
Quem primi colimus, cui pineus ardor acervo
Pascitur, et medium freti pietate per ignem
Cultores multa premimus vestigia pruna ;

Da pater hoc nostris aboleri dedecus armis
_ Omnipotens. — J ZEn. lib. xi.

' Servius explains the term acervo, “ Pyra coacervatione lig-
* norum.” Perhaps he did not use the word as denoting a fu-
neral-pile, as it also signifies a bonefire. There is indeed no
reason for supposing, that Virert referred to the burning of
the dead. We learn the meaning of this language from the
testimony of Privy: “ Haud procul urbe Roma in Faliscorum
“ agro familiz sunt paucee, quae vocantur Hirrre : que sacrifi-
Taig eanEO, quod fit ad montem Soractem Apotiini, super
“ ambustam ligni struem ambulantes non aduruntur.” Nat.
Hist. lib. vii. c. 2. The same species of worship is described
by Srxrus Irauicvs, lib. v. ver. 175. bal

I need scarcely observe, that, as AroLto was the same Pcih
the Sun, the passage affords a proof of the striking analogy be-
tween his worship among the Romans, and that which has been
already illustrated. Did we know the particular day annually
coaggroted in this manner, the coincidence might be still
more remarkable.

The early Greeks ascribed the same efficacy to fire. Homer,
accordingly, makes ULysszs, after the slaughter of those who

al sought.

110 ON THE ORIGIN OF CREMATION,

sought to rival him in the affections of Prnexore, to purity his
house from blood by the use of fire and sulphur:

Oirs Sesion vend xeoxay cxos, dios Oe pros mde
"Oden baisbow Heyagor.
Odyss. lib. xxii. v. 481.

As we certainly know, that the ordeal by fire was used in
the times of heathenism, there is no reason to doubt that it
originated from the same persuasion as to the purifying virtue
of fire. The person who passed without injury, bare-footed
and blind-fold, over nine glowing ploughshares, was said to be
purged from the crime of which he had been accused. The
names given, in various instances, to this species of trial, ex-
pressed the same idea. In the language of Iceland it was de-
nominated skirsla, from skir-a purgare. The learned Lunp
traces the Gothic term ordel, urdel, perhaps rather fanci-
fully, to Heb. ur ignis, as denoting judgment by fire*. In
the Latin of the dark ages, the act was designed purgatio vul-
garis; and the person was said, per calidum ferrum se purgare,
or ferro candenti se purificare. It may be added, that, as the
other mode of ordeal was by water, whether cold or hot, it ap-
pears that the principal tests of imputed criminality bore a
strict analogy to the two great means of purification acknow-
ledged by the ancients,—fire and water. '

As a proof that the ordeal by fire was a remnant of pagan
worship, the justly celebrated Du Cancxr refers to the testimo- .
nony of SopHocLes.

"Hyey F eroiwor nat pvdeus cegew egos,
Kai wie diéerew, xock bees oguapmoréire
Antigon. ver. 270.
") “ We

* Ture Glossar. voc. Ordela.

OR THE BURNING OF THE DEAD. 111

“ We were prepared to grasp the burning irons in our hands,
“« and to pass through the fire, and to adjure the gods.” Pa-
cuymergs has remarked, that uvdgos, or the burning share, was
said to be ays, or holy, because it had been blessed by the
priest *. ;

8. It was believed by some, that by the action of fire, the
soul was completely loosed from all its corporeal bonds. Trr-
TULLIAN charges some philosophers with holding, that even af-
ter death, certain souls continued in a state of connection with
the bodies which they had formerly animated : “ Ita argumenta-
“ tiones emendicant, ut velint credi etiam post mortem quasdam
“ animas adherere corporibus }.” He asserts, that PLaro was of
this opinion. But the passage to which he refers, can only be
viewed as a proof that Prato believed the immortality of the
soul. It is the apologue introduced by him in his Republic,
conceming Hervs the Armenian, who is said to have revived,

when he was laid on the funeral-pile, twelve days after he fell
in battle t. ~Macrosius, however, gives the same account of
the doctrine of this philosopher. For, according to him, Pate

asserts tha the souls of those who die by violence wander long
+ ie - around,
ede ;

° Ap. Du Ca 3, voc. Ferrum Candens.

As the Greek word ve has been deduced from the Hebrew sik, ur, pro-
peny de

count of the natural subserviency of fire to purification, as well as the ri-

tual use of it with this view, it is possible that the verb purgo may have been
formed quasi mig ayo, as originally signifying to lead, or make to pass through
the fire. Perhaps the language of the ancient Latin poet Navius, in the use
of the phrase puriter facere, may be considered as favourable to this etymon of pu-
_ rus; Sequere me, puriter volo factas, igne atque aqua volo hunc accipere..
_ Ap. Non. Marcexy. Gothofred. 775.

+ De Anima, p. 501. edit. Paris. 1616..
t Puar. Republic. lib. x. vol. ii. p. 614.

112 ON THE ORIGIN OF CREMATION,

around the body or the place of its sepulture; the soul being
more and more fettered to the mortal part: “ Exitu autem coac-
“ to, animam circa corpus magis magisque vinciri. Et revera
“ ideo sic extort anime diu circa corpus ejusve sepulturam, vel
“ locum in quo injecta manus est, pervagantur*.” “ On the
“ contrary,” he says, “ those souls, which, during life, are loosed
“ from corporeal bonds by a philosophical death, are translated
“ to heaven even while the body exists.” _

It is not perfectly clear, however, whether Macrozrvs assigns
this doctrine to Piato himself, or to his disciple PLotinus, who,
he says, carried the principles of his master still farther. In
the passage to which Macrosrus seems immediately to refer,
Prato does not speak of those who die by violence, but in ge-
neral of men leaving this world under moral contamination +.
Elsewhere, indeed, he says, that, besides the immortal soul, the
gods have placed in the body of man éidos Puyis bara, “ a kind
“ of mortal soul.” This, according to his idea, includes the
will and affections f.

TerTuLuiaN has ascribed the same opinion to Democritus ;
observing that he reasons from the growth of the nails and
But it would seem that here he has rather’
mistaken the meaning of the language of Democritus ; as all
that we can certainly infer from it is, that he held the ee
of a future resurrection.

JamBuicuus says, that “ fire destroyed whatever it ae ma-
terial in the sacrifice, purified, and released it from the bonds

“ of

* Macros. Somn. Scipion. lib. i. p. 87. edit. Lugd. 1560.

+ He expresses his sentiments in the following terms: "EyBgi:s 0: ys, @ Dire, rex0 1 soba
men Cover xaei Ceegu, noel yeadec, nol oguror' 2 3: nal Byoure 4 rorcurn Puyn, Baguveros ve xl
Anita mar es gay ogeToy <To7mOY, Qdew T& csidols te noel gdev. Phed. Puar. Oper. I.
p- 81.

+ Psat, Timeus, Op. iii. p. 69. || Terrunuran, ubi sup.

OR THE BURNING OF THE DEAD. ‘113

‘of matter, and by reason of its purity made things fit for the

“ fellowship of the gods.” ‘“ Noster ignis actionem divini ig-

“ nis imitans, quicquid materiale reperit, in sacrificio, destruit,

“ et admota purificat, et a vinculis materiz solvit, ac propter

“ nature puritatem ad deorum communionem idonea fecit *.”

According to Lucan, “ the power of the flame carried the

“ soul into the eternal world.” Speaking of the manes of the
dead, he thus expresses the general belief:

Quos ignea virtus

Innocuos vite patientes etheris imi

Fecit, et zternos animam collegit in orbes. __
Pharsal, lib. ix. ver. 0.

And Ovm says of Junius Casar:

Nam Patris Augusti docui mortale fuisse

Corpus ; ia xtherias Numen abiisse domos.
Pont. lib. iv. Ep. 13.

“ The Romans burned the bodies of the dead,” says Servius,
“ ‘ut stafim anima in generalitatem, id est, in suam rediret na-
“ turam +.” This corresponds with the account given by S1-
t1vs Irauicus, when describing the funeral of Pautus :
—— Recens crepitantibus undique flammis,
Aithereas anima exultans evasit in auras.
Lib. x.
i
Ovip may be viewed as expressing the general persuasion,
that the soul was not completely separated from the body, till
the latter was consumed on the pyre, when he thus declares
the ardour of his friendship :

Spiritus et vacuas prius hic tenuandus in auras
’ hit, et in tepido deseret ossa rogo;
Quam subeant animo meritorum oblivia nostro.
Trist. lib. i, Eleg. 4.

Vor. VIII. P. I. @P These

® Jamauicu, de Myster. Cap, de Ratione Sacrific.
+ Serv. in Zr. lib, iii.

114 ON THE ORIGIN OF CREMATION,

These incidental intimations of the sentiments of the an-
cients, coincide with the information which the accurate Evu-
staTuivus has given us on this subject. “ It was a custom,” he
observes, “ among the Greeks to burn their dead, which cus-
“ tom still remains among some northern barbarians : and they
“ do this to indicate, that the spiritual part of man, being
“ carried upwards as in a chariot of fire, rises with heavenly
* objects, but that the earthly remains behind *.”

The Jews, as Grorrus has remarked, at least as early as the
age of Justin Marryr, had adopted the idea that the souls of
the dead lingered about their bodies, and were subject to the
power of demons. This opinion, he adds, passed to the Chri-
stians, as appears from the reasoning of Justin with the Jew
Trypno, concerning the Witch of Endor, who, he thinks, really
raised the Prophet Samuet +. Jusrin, indeed, in another
place, appeals to necromancy (vexvouerréas), as a proof of the
separate existence of the soul {.

The same idea, that the soul for a considerable time after
death retains some intercourse with the mortal part, is expres-
sed by some later Jewish writers. They hold, that for twelve _
months after this event, the soul is more or less with the body,
hovering over it: and hence some have been induced to go and
dwell among the tombs, and inquire at spirits ||. Others, how-
ever, greatly limit this time: “ For three days,” they say, “ the-
“ soul goes to the grave, thinking that the body may return ;

“ but

\ ’ ~
* “Ori bos gy “EAAnce xo THs vaxgouse 0 3) xe) eg exe mee gee meeves Tick Tay Boptiay Bagagar.
3 Reiss en: rag en 49 sane 3 « seas
oroiouy oe TOUTO EXEbVOL, 7% e0s ewer Tov FO ey decoy Tou edeairrov eevaaPoenbey acne ey ORNATE

TH uel, meorpesbes seis dugdvoss. To OF vyHivor, xerw meses EusTaTu. in Iliad. A. ver. 52.
+ Gror. in Matt. viii. 28. { Apol. ii. p. 65. ed. Lut. Par. 1615,
) Nishmat Chayim, Par. ii. c, 22, p. 81. T. Bab, Beracot, fol. 18, 2.

OR THE BURNING OF 'THE DEAD 115

“* but when it sees the figure of the face changed, it goes away,
“* and leaves it *.”

The Greeks and Romans found this doctrine indispensably
necessary for the support of a very considerable branch of their
system of polytheism. As they ascribed to their heroes or de-
migods a corporeal substance that was partly immortal, they
founded this strange notion on another which was not less ab-
surd. They believed that this partial immortality proceeded
from their being in part descended from the gods. Hence, as
they supposed that their bodily frame originated partly from
mortal, and partly from immortal seed, they persuaded them-
selves that the fire of the funeral-pile effected a separation be-
tween these heterogeneous principles; and that not only the
soul, but, as it was sometimes designed, the divine portion of
the body, was carried into aemaosnll Of this extravagant no-
tion we find many vestiges in their writings. Hercuxss, it is
said, consecrated himself by burning ; and was, in consequence
of this devotement, admitted into the number of the immortal
gods. Hence Catirmacuus says of him ;

"Ov yae oye Devyin ree veo oovi yvie bewbels
Tlavour’ adyQaying.
Hymn. in Dian. ver. 159.

It is evident that the poet ascribes immortality to the mem-
bers of the hero. - Some have confined the term yi« to his
soul. But the language will not bear this restriction. For
the very design of it is to shew, that Hercutns did not lose his
appetite with his deification, but ate as keenly as he had done
during his mortal life, and even while he followed the plough ;

_ and that, therefore, it was necessary that the Amnisian nymphs
Fe 2 should

"% Bereshit Rabbay § 100. f. 86.

116 ON THE ORIGIN OF CREMATION,

should exercise all possible diligence that they might regularly
provide venison for the table of the god. The Emperor Ju-
LIAN affirms, that “ while Hercunzs was a child, his divine bo-
“ dy made gradual increase *.” The fire, then, was believed
to consume the mortal part only ; that the soul, with that por-
tion of the corporeal frame which was deemed originally im-
mortal, might be received into the celestial regions. Such was
the virtue of the flames, that, like those of the phoenix, they
removed the infirmities of age, and communicated eternal
youth. Hence Turocritus, who gives the same honour to
ALEXANDER the Great, and to Protzmy [Lagus, as to Hercu-
LES, Says :
“Orrs oar Keovidas meréwy elerrero yeas:
Idyll. xvii. ver. 24,

Or, as it is rendered by our English translator ;
On each, great Jove reprieve from age bestow’d,
And call’d immortal, rais’d into a god.
Hercutes is, by the tragic poet Seneca, made to give the
same account of his apotheosis to his mother AtcMENa, in a

passage which exhibits the heathen creed on this point more-
distinctly perhaps than any other now extant,

Quicquid in nobis tui

Mortale fuerit, ignis evectus tulit ;

Paterna ceelo pars data est, flammis tua.

Hercul. @é. ver. 1966.

This wonderful virtue of the funeral pile, was not, however,
entirely confined to demigods. For Scytia, who had been’
slain by Hercutes, was raised from the dead, and rendered -im-

mortal

* ‘Heaxngs 22 Abyeras maiDlov ryeviobees, noi nad mingiy dura rd oie +o Deroy ETIOEymn
Juxtay. Imp. Orat. vii. p. 408, ap. Spannem. Obsery.:in Catiimacn. p. 240.

«

OR THE BURNING OF THE DEAD. 117

mortal, by her father Puorcys; who, by means of the vivifying
flames, infused new life into her stiffened limbs :

"Hy abbis ras ne

Daeuas nareribay Ao@yiory dounrare,

, ? fi, > 7, yas
Acaroy 8 recusouy gdasay becy-
Lycopuron, Cassandr. ver. 44. V. Porren, ii. 208.

It is pretended that the fire, by which the body of Hercurzs
was consumed, was kindled by the thunderbolt of Jove; and
that, in this manner, the son was called into the presence of his
divine parent : Eir éravqyarye die oe Keouwvis mueog re0g eauroy *.
As the Greeks and Romans forbade the cremation of any who
had been killed by lightning +, it is not improbable that this
prohibition might originate from the idea, that such persons
had been already purified, or consecrated, by the stroke of fire
from heaven.

It may be observed in addition, that the rites of apotheosis;
or consecration, an honour given to the Emperors of Rome,
evidently include the idea that the soul was not completely re-
leased from its mortal entanglements, save by the influence of
fire. The body, indeed, was previously burned: But an image
of the person in wax was substituted; and consumed on a lofty
and costly pile, with all possible pomp and solemnity. This
pile consisted of four different frames of wood, gradually de-
creasing in their dimensions, and placed one: above another.
When the fire had nearly reached the fourth or highest frame,
an eagle was let loose from it, “ which, ascending with the
“« flames towards the skies, was supposed to carry the prince’s
“ soul to heaven t.” On some of the coins, struck in memo-.

ry.

* Juuian. Imp. Orat. vii. p. 408.; ap. Spannem. ut sup. p. 241.
+ V. Gorner. de Jure Manium, lib. i. c. 3.
+ V. Heropian. Hist, lib, iy.

118 ON THE ORIGIN OF CREMATION,

ry of consecrations, the emperor appears carried aloft by an
eagle *. Or, perhaps, the figure here exhibited is rather to be
viewed as the emblem of his soul.

Y. The soul itself was thus supposed to be purified from the
contamination which it had contracted in its embodied state.
The ancient Gymnosophists of India, of whom the Brachmans,
now called Bramins, formed one sect, and the Germanes, Her-
muines, or Sermanes, another, were wont to burn themselves
alive +; although, in our day, they require this sacrifice of
their wives only. ‘That they ascribed some peculiar virtue to
fire as thus applied, might be inferred from the language of
that Indian, who, when he cast himself into the flaming pile at
Athens, said to the astonished spectators, “ Thus I make my-
“ self immortal {.” But perhaps the inference is confirmed
by the account which Porrnyry gives of the reason of this act
of suicide. Having observed, that they who are about to de-
vote themselves in this manner, first coolly receive from those
around them the commissions which they wish them to carry
to their friends in the other world; he subjoins, “ They cast
“ their body into the fire, that they may separate the soul from
“ it in a state of the greatest possible purity.” This at least
seems to be the natural meaning of the words of Porpuyry ;
wuel 70 capes mugadorres, Oxws Oy nabugurarny cmonelacr ToD caput
ros yy spoyny ||.

Lucran, when speaking of the self-devotement of Hercuxss,
which he attributes to mere ostentation of fortitude in suffer-

ing,

* V. Havercamp. Nummophylac. Reg. Christin. p. 100, 101.

+ Oavarw BE taxvtss arodidiarr xe0, xalimte xel cs Tov Iiday yuouvoroPigai parciw Mer,
Ciem. Avexanpn. Stromat. Lib. iv. p. 351.

} Nic. Damascen. V. Hydriotaph. p. 3.
|| De Abstinentia, lib. iv. sect. 18.

OR THE BURNING OF THE DEAD. 119

ing, introduces the Brachmans, and refers:to the history of Ca-
LANUS, who, leaving his own society, followed ALEXANDER the
Great from India. “ The Brachmans,” he says, “ do not leap
“ into the fire like Onrsicrrrus, the Governor of ALEXANDER,
who, it is related, when he saw Catanus burning, flung him-
“ self into the flames ; but after they have erected the funeral-
“ pile, standing immoveable beside it, patiently allow them-
“* selyes to be accosted, then ascending it with dignity, are
* consumed, not shrinking in the slightest degree from the ap-
“* proach of the fire *.” But, as it was the design of Lucran to
ridicule the philosophers, he assigns no other reason for this con-
duct than the love of vainglory. To the same motive does he
-ascribe the act of PrrEcrinus, a Stoic, or, as he says, a Cynic
philosopher, who devoted himself to the flames.

Cexsus the Epicurean, however, as quoted by OricEn, view-
‘ed this suicidal act in a more favourable light. His testimony
‘corresponds with that of Porruyry. His language intimates,
that, what virtue soever might be ascribed to the flame of the
funeral-pile, in ordinary circumstances, the effect was. supposed
to be far greater, if any one consigned himself to it alive. Ont-
cen thus expresses his sentiments : “ Cexsus says, that it is im-
« pious to violate the laws of our country in regard to the bles-
“ sed* termination of life (as it is accounted) by the funeral-
“ pile, into which those who voluntarily cast themselves are
“ perfectly purified in their aberration from life f.”

QuinTILIAN ascribes the same purifying efficacy to the fune-

ral-pile. Speaking of the soul, he says ; “ Quoties humani pecto-
(74

7 66

ris
* Lucian. de Morte Peregrin. Oper. ii, p. 576.

* “Huiy 6 Kéaoos, was By dot moegarvesy voperss merelsc—mtel Ts peacrecdgtoy Euvees Yevocamn roy

t » cad vv Y eee) ’ ‘ © LU / ~ ‘ \ ~ \ x > : ~

Biov eeabay. motvras xacbcciger bas TBs tauTEs mreepcO1oavr ces TH Wugi, nak Th uct Wugos amanrrcryy

7% amo 72 Bis. ORIGEN. cont. Cexs. Lib. v. p.249. “ Kedaiger$at,” says the learned Stuc-

Klus, “idem quod Avyaiv ; expiare, resecrare, purgare, expurgare, purificare.” Sacr. Sa-
erific. Descript. p. 123...

ae

120 ON THE ORIGIN OF CREMATION,

“ ris carcerem effugerit, et exonerata membris mortalibus levi
“ se igne lustraverit, petere sedes inter astra *.”
Servius, when explaining the language of Virert,

Aliw panduntur inanes
Suspense ad ventos: aliis sub gurgite vasto
Infectum eluitwr scelus: aut exuritur igni

remarks, that he “ speaks poetically concerning the purgation
“of souls ; for he alludes to what the philosophers said.” He
then proceeds to shew, that there was a threefold purification
of man, by earth, by water, and by air ; that the earthy purifica-
tion denoted that which was made by fire, which has its origin
from earth; and that this was necessary for those whe had in~
dulged in sensual enjoyments }.

As it was accounted unlawful for Christians to burn their
dead, TerruLuian assigns as one reason for their rejection of
this practice, that they had already received the benefit of a pu-
rification far superior. “ Et cremabitur,” he inquires, “ ex dis-
“ ciplina castrensi Christianus, cui cremare non licuit, cui —

Christus merita ignis indulsit ? {”

it is well known that the Platonists denominated the end of
the present state of this world ayarvegacis, as believing that it
should be purified and refined by fire; and that to this change
the Stoics gave the name of ézzvgasig. As it is equally certain
that many of the dogmas of the Oriental, of the Platonic,

and

* QerntiniaN. Declam.*x.

+ Loquitur quidem poétice de purgatione animarum: tangit tamen quod phi-
tosophi dicunt. Nam triplex ‘est hominis purgatio. Aut in terra purgantur :
que nimis oppress sordide fuerunt, dedite scilicet corporalibus blandimentis,
enim transeunt in corpora terrena; et hec igni dicuntur purgari. Ignis enim
ex terra est, quo exuruntur omnia, nam ccelestis nihil perurit. Serv. in 4-
neid. Vi. ver. 742.

+t Tertunitan. de Corona Militis, p. 292.

OR THE BURNING OF THE DEAD. 121

and of the Stoic, philosophy were early incorporated into the
Christian system; it has been asserted by several learned wri-
ters, that the Popish doctrine of a middle state, or of the puri-
fication of souls by fire, was borrowed from that of the ézqveu-
o. The doctrine of purgatory, indeed, is nearly allied to the
ideas which the gentiles entertained concerning the efficacy of
fire in preparing the soul for the abodes of Elysium.

It has also been observed, that the sacrifices which the Greeks
denominated revere}, were offered with the same design. Some
have supposed that these sacrifices for the dead received this
name, because, being the most sumptuous of all sacrifices, the
greatest part of them was consumed *. But there is another
interpretation of the term, which is more probable. They
seem to have been thus denominated, as perfecting whatever
had been deficient in the merit of the dead, and as securing
their liberation from suffering in the eternal state f.

10. I shall only further remark, that this igneous purifica-.
tion was intimately’ connected with sacrifice. Though, as has
already been observed, we cannot view this practice as origina-
ting from the tenets of any particular school ; sufficient proof’
has been brought to shew, that it was viewed as a solemn act
of religion : and it may naturally enough be supposed, that the
philosophers who considered fire as the principle of all things,
would take advantage of a custom which was pretty general in
their times, as affording an argument that seemed to lend its.
aid to their peculiar system. As this custom: was observed, not.
merely as a religious rite, but as. am important means of puri-
fication ; as it has been so generally diffused, although doubtless.
abhorrent from the feelings of humanity; I have at times been:

Vou. VIIL. P. I, Q inclined:

* Sur. in voc.

+ V. Gane’s Court of the Gentiles, Part IIT. B. ii, c. 2. § 11.

122 ON THE ORIGIN OF CREMATION,

inclined to think, that, at an early age, the cremation of the
body might have been immediately meant as an act of expiatory
sacrifice. Of this, however, it must be acknowledged, we have
no direct evidence. But the want of this evidence is not a de-
cisive proof that the conjecture is totally unfounded. The ori-
gin of the practice itself being buried in the obscurity of ve-
ry remote ages, almost beyond the period of fabulous history ;
it is by no means surprising, that we should be as much at a
loss in regard to the primary design. On a subject of this
kind, even the feeble voice of conjecture ought not to be with-
held, as no other can be heard; nor should it be totally disre-
garded, because at times mere conjecture has eventually led to
the discovery of truth.

It is highly probable, that this custom had its rise in the dis-
tant regions of Scythia, if not in Hindostan. As we learn
from the earliest accounts of the inhabitants of this interesting
peninsula, which have reached our times, that even when these
were written, they not only burnt the dead, but that the living
often devoted themselves to the flames; it may afford ground
for conjecture that the latter practice preceded the former.
Those who viewed it as a signal act of piety for a man to cast
himself into the funeral-pile, and as a complete atonement for
all the transgressions of his past life, though they could not ri-
val him in intrepidity, might, like those who affect liberality in
their latter wills, wish to imitate him as far as possible, by de-
voting the mortal part to the fire after the extinction of life.

It may perhaps be supposed, that this act of self-dedication
to the flames was originally meant as a consecration to the sun.
Yor, though the Persian fire-worshippers objected to cremation
as a profanation of their deity, we are not warranted to con-
clude, that all who concurred with them in worship entertain-
ed the same idea. While we know that some of the ancient

, Brachmans

OR THE BURNING OF THE DEAD. 123

Brachmans devoted themselves to a fiery death, we are assured
by Srernanus Byzanrinus, from Hrerocres, that they were
chiefly consecrated to the sun*. ‘tian expressly declares,
that. Catanus, the Gymnosophist, after he had ascended the
funeral-pile on which he devoted himself, adored the sun which
shone on him; and that this was indeed the signal which he
had agreed’ to. give’ to. the Macedonians, that they should set
fire to the pile +. Lucraw. gives a similar account of the death
of Perecrinus, who, although a Parian by birth, seems to have
imitated the customs of the Gymnosophists. The pile being
kindled, “ he called for incense; which when he had received
“ from some one, he cast into the fire. Then looking stedfast-
“ ly towards the meridian, (for the meridian was concerned in
“ this tragedy), he said, O! ye maternal and paternal demons,
“ receive me graciously ! Having said this, he threw himself
“ into the flames.” He subjoins, “ It has been lately report-
“ ed, that, as he ascended the pyre, he saluted the rising sun,
“ as it is said the Brachmans are wont to do t.” It. merits ob-
servation, that the Bramins of our own time daily pay their de-
voirs to the sun ; not considering him, they pretend, as the pro-
per object of worship, but as the visible representative of the
Supreme Being. Incense, I am assured on good authority, is
uniformly used by them, in the manner above described, in the:

Q2 inhuman:

eee ; : :
™ Beceyeecivay ide QUAcv avdeav, Pirorapay xal bois Pirwy grlw oe et risce nabercromcvav.
SrePu. BYZANT. voc. Beaypmires.

.
HY; ] : 3
Kal o pty Hass cevrov HeordounAsy : @ O& auroy meorewves > nal vero gy TO cUbne es +O
mare? mueay ois Mexedoct, ABELIAN. Var. Hist. Lib. v.c. 6.

£* ‘Eve ares AiGavorey as tmiocros em) ro mie. week aveedovros Thv0s, emtoans Te, noe eearny &
Thy peconubeiey amobAtway, nol yee 3 7T8t0 eos Thy “eerste & ay Py pont Dect eoves penrea-
ot xak TOT EMO. Shard: fe. évpeeverg.—Kas yee 02 rade ™ meoregice Beledore, ws 7 @05 avorovre.
Tay rw aorerapesves, womep autre Se TB; Beoryzcvas Derr mosci, emioyrerdas whe meds, Lis -
cian. De Morte Perecrin. Oper. ii. p. 584,—586, .

124 ON THE ORIGIN OF CREMATION,

inhuman act of burning the living with the dead. This act is in-
variably performed in the vicinity of a river. For all the ashes
of the dead are collected, and completely dispersed on the wa-
ter; as if they accounted both these elements, which other
nations used for purification, necessary for perfecting this hor-
rid consecration.

There can be no doubt that the Greeks and Romans also
worshipped fire, under the names of Esi« and Vesta. It may
be remarked by the way, that as the Latin name of this deity
is evidently from the Greek, some learned writers have with
great probability traced the Greek word to that country in
which, it has been supposed, fire-worship had its origin. The
Chaldaic term Zsth signifies fire, synonymous with Hebrew
Tw, ashch *.

Whether cremation was originally meant as a sacrifice or
not, it cannot be denied that a variety of circumstances were
conjoined with it, which had the closest connexion with this
act of religion.

The funeral-pile was erected in the form of an altar. Hence
the language of Vircit, when describing the obsequigs of Mr-
SENUS 3
Aramque sepulchri

Congerere arboribus, czloque educere certant.
fin. lib. vi.

——

Cremation was accompanied with the oblation of victims.
Originally the blood of captives was shed. Acutuzs sacrificed
twelve gallant Trojans in honour of his friend Parrocuus fF.
Gladiators were afterwards substituted for captives. These

were

* V. Srucku Sacr. p. 151.; Pier. Hieroglyph. fol. 135, b.; Bocuart, de
fEn, p. 13.

+ Iliad. ¥ ver. 175.

OR THE BURNING OF THE DEAD. 125
\

were by the Romans called Bustuarii, because their blood was
shed before the bustum, which was the designation given to the
funeral-pile, after the body was combustum, or burnt; or, as
others say, quasi bene ustwm, thoroughly burnt or consumed.
For it bore the name of rogus, while the fire continued to
burn; because, as Servius explains it, during this operation
the attendants continued rogare, to call upon or invoke the
manes of their departed friend. They sometimes sacrificed
beasts, as oxen, swine, &c. which they threw into the blazing
pile.
Multa boum circa mactantur corpora morti,

Setigerasque sues, raptasque ex omnibus agris

Tn flammam jugulant pecudes.
“En, lib. xi,

It must be acknowledged, however, that while the ancients,
in some passages, unquestionably speak of these offerings as
made to the manes, or ghost, of the person whose funeral was
celebrated, in others their language can apply only to the Di
Manes, or infernal gods. This inconsistency causes consider-
able difficulty in attempting to form a judgment with respect
to their proper design in these oblations.

When the body was consumed, they extinguished the fire by
pouring wine upon it. This is said to have been done, that
they might more easily collect the bones and ashes. But even
this has much the appearance of a sacrifical act, and may ori-
ginally ‘have ‘been ‘meant as a libation. Water, because of its
purity, might otherwise have been preferred for extinguishing
the flames. From the manner in which Homer describes the
employment of AcuitiEs, while watching the flaming pile of
Parrocius by night, it would seem: that he continued to pour
wine on the ground, as a libation to the manes of his friend :

‘Osvov

126 ON THE ORIGIN OF CREMATION,

Ne , , ~ ay ~
Ojvoy aPvocopnevos ycepce 65 y 4rd deve 05 Y Usa,
Won HIEANTLOY TlareoxAnos OesAoro.

Tliad. ¥. ver. 220.

Prato informs us, that the ancient Greeks hired female
mourners, whose office it was to. bewail the dead, and to make
libations *.

It may be also observed, that they evidently wished that the
wine, used on this occasion, should as nearly as possible re-
semble blood. Thus, in the account given of the funeral of
Hecror, we find it expressly mentioned that the wine with.
which the remains. of the fire were extinguished, was dark-co--
loured,

~ \ \ +X , Ld ww
Tlgaroy (ee? LATO VCH oPeouy asbors Ola

Ildowy oxorooy emerye mugos puevoc:
Thid. a. ver. 791.

Now, this is the very language which the same illustrious:
pet had employed to denote the libation by Curysrs, the
priest of ApoLto, on the joints of the hecatomb, which he of--
fered as an.expiatory sacrifice for the Greeks.

Kate 3 emi oyilns 6 yéewr, ext 0 ciBorce osvor.
Ibid. a. ver. 462.

I have already adverted’ to the Indian practice of casting
frankincense on the funeral fire. As the use of incense has
from time immemorial been an established rite in. sacrifical
worship, it appears that it was not unknown to the Greeks and
Romans, in celebrating the obsequies of the dead. Kircuman

has

* "lepeie re meorPelrovres med TBs exPoghs +H vengov, xa eyyurersins weremeumousvol PLAT.
Minoe, Oper. ii. 315.. KincHMan supplies some observations on this singular rite. De
Funer, p. 370.

OR THE BURNING OF THE DEAD. 127

has remarked, that he finds incense mentioned among other
spices, which were thrown into the funeral-pile. The great
expence in multiplying these might latterly proceed from mere
ostentation. In some instances, they might be merely meant
to overpower the fetid odour arising from the act of cremation.
But it may be supposed, that the use of incense had originally a
sacrifical signification. Lucan, when describing the funeral of
Pompey, mentions this as the only odoriferous substance that.
was burnt with the body *.
Non pretiosa petit cumulato thure sepulchra

Pomrstus, Fortuna, tuus.
Pharsal. lib, viii,

Without particularising the games celebrated at funerals, or
the feasts connected with them, which were on other occasions
accompaniments of sacrifice, I shall only add, that besides the
pyre, which had the form of an altar, another altar was erected,
after cremation, immediately before the sepulchre. This recei-
ved the name of acerra; and is by Servius expressly distin-
guished from the funeral pile +.

* Kircuman. De Funeribus Romanorunm, p. 226.

+ In dn, lib. vi.

VI

oe i

“~ Fiaene ‘aig hi Boetetaey

‘vet | eae 30s em mt @ cone

ott ve faces ra cope ‘cadets ani:
toe ES saliey tiictalk qh tondi wieteately
vender inch Fetadsdpeettowad tebe cve, cach

eh Ta aay ue sph Aikertrs me
Iestaare

re’

, a ? oie as aaa ‘ay a We /
| tid be scorn
A - wheres a + nk

= . tf ate a i tea
Wrepre ett! ican i phen 2

bt etre «A teaehvanra

; "et A pth
7 a aletoeiul ja bean ‘ofS:

De we ¥ih30 no eto) j

: ‘att pebpimedl imi bho iho

hapa te vane HN pays.

addon 7 a sa
| fenbatpeaths gee fi cath
ee ee

ete Pee hcg’ ‘im ee est Oiaciw sad .*
ee wc taal goa | soba se
Ga bean y we eh bah te ied sad Ga
Bharat we : ca RA, ta ce f
ee ee wig Swe pt ae

a
ori ae) gui iia 8 Na Staphamia. eat shania
’ , vu
& at ARPS tory cae ‘”
I sk Cede Oe RY OO
7 " bese \ ae wit o® on

ont ww a ~~

pe 4e*>”

a a
oftt.]

VI... Additional Communications respecting the Blind and Deaf
Boy, Jamzs Mircuexrt. By Joun Gorvon, M. D. F. B.S.

Epin.

{

(Read Nov. 20. 1815. )

55 HE following circumstances respecting the Blind and Deaf

& Boy, James Mircuetr, have come to my knowledge since
the publication of Professor Srrwart’s Memoir; and I doubt
not but the Society will think them worthy of being recorded.
They are derived from the most accurate and authentic of al]
sources, the boy’s sister, Miss Mircuett.

_In the month of April 1814, Mr Parker, an English gen-
‘tleman, (distinguished, as I have since learned, for his active
benevolence,) did me the honour to wait upon me, to commu-
nicate a plan for the instruction of young Mircuetx, which had
some time before occurred to him, and which he was very de-
sirous should be put to the test of experiment. This method
seemed in no respect inconsistent with those principles which
in all circumstances appear to regulate the acquisition of lan-
guage; and IJ therefore expressed my willingness, to promote,
by every means in my power, the object which Mr Parker
had in view.

Vou. VIII. P. I. R Mr

130 ADDITIONAL COMMUNICATIONS

Mr Parker, accordingly, took the trouble of getting an alpha-
bet cut in wood ; the letters of which were in relief, and in sepa-
rate pieces, each about an inch long. He provided, also, two other
alphabets, one of pasteboard, and the other of metal, with the
letters of the same size, and detached, as in the former. These
alphabets I transmitted to Miss Mrrcnett on the 2d of June;
informing her, at same time, of the purpose for which they
were intended; and expressing my anxiety, that she would lose
no time in giving the plan proposed a fait trial. Particular di-
rections for the use of the alphabets were drawn up by Mr
Parker; and I took the liberty of adding only a few general
hints ; being well aware how unnecessary it was to go into
the minutie, when addressing so judicious a preceptor.

The outline of the plan was simply this: The name of any
familiar object being chosen, such as egg, bread, sugar, arm, &c.,
the letters forming the word were to be put together by Miss
Mrrcnett, exactly as they are arranged in print. Mrrcuetr
was then to be made to touch, first the object, and then this
word, in immediate succession, as often as possible; so as to
form a close association in his mind, between the thing and its
tangible name. It was left entirely to Miss Mrrcnetx’s judg-
ment, to employ such means as she deemed best, for securing
her brother’s perseverance in the task for such a length of time,
as might enable him to perceive its object: And in the event
of this primary and fundamental step being gained, the experi-
ment was to be prosecuted, according to similar principles.

The following is a copy of a letter which I received from
Miss Mircuext, dated Nairn, the 30th June.

- “ Ihave been from home during these last ten days, which
has prevented my sooner acknowledging the receipt of your
favour

RESPECTING THE BLIND AND DEAF BOY. 131

favour of the 2d instant, accompanying a parcel from Mr Par-
KER, to whom we consider ourselves very much indebted for
the interest he takes in my brother. Have the goodness to
make offer of our warmest acknowledgements to him, and say
that I shall, with much pleasure, avail myself of the liberty he
allows me, of informing him of the progress made, in the plan
he has so ably sketched for my brother’s instruction, which I
mean to attempt immediately, and: shall not be easily discou-
raged by not succeeding at first. If I can once interest my bro-
ther, by affording him any gratification, in my communications
by the means of letters, I shall have very great hopes of suc-
cess. I shall first try the pasteboard letters, as I think them
less likely to distract the attention than the wooden ones.

“« My brother was twice at Ardclach of late. The first time,
he probably found his way there by chance, as) he had not been.
at Ardclach before, since he came to reside. at Nairn ; 3 but the

md. time, he must have gone intentionally, as there:was on-

e one day between the two visits. I have seen Mrs Macsran
since these visits, and inquired particularly respecting his con-
duct. The first day, after having taken some refreshment, he
went through the different apartments of the manse, examin-
ing, by touch, the furniture, &c. and seemed to miss a closet-
door, which had. been shut up after we left the place. He did
not betray any particular emotion, upon thus visiting, for the
first time, a house which had been for so many years his home;
but when he had satisfied his curlosity, seemed anxious to get
away, and returned directly to Nairn. On the second visit, he
found workmen employed i in taking down the kitchen, (a part
of the 1 repair which the manse was then undergoing,) and after
standing some time, evidently very much displeased at the
_work of destruction which was going forward, he came away in
very bad humour, and could not be prevailed on to return and
R 2 go

132 ADDITIONAL COMMUNICATIONS

go into the house. He did not discover the least wish to visit
the church-yard either time.

“ T had an opportunity of observing his conduct with regard
to a dead body very lately ;—the body of an old gentleman, a
near neighbour of ours, and one who had been very kind to

him, frequently indulging him with a pipe and tobacco, his fa-
* vourite gratification. I brought him to the room where the
body was laid, and allowed him to feel it, which he did very
willingly, not shrinking as upon a former occasion, but seem-
ingly rather anxious to examine it. When he had done so, he
stood for a few seconds, rather thoughtful ; and this was follow-
ed by a smile, with, I thought, something of wildness in the
expression of the countenance. He then came away very wil-
lingly with me, but not before he shewed that he recognised
the person, and was sensible of the situation. This he did, by
making his usual sign for smoking, and by putting his hand to
the ground, his sign for interment. He discovered a wish to
learn when the ceremony was to take place, (by a slight incli-
nation of his head to one side,) which I endeavoured to inform
him of; and he kept constantly in the way until it was over;
frequently going to the apartment where the body was kept ;
but without discovering sorrow, further than now and then ap-
pearing rather thoughtful.

“ These particulars are perhaps of little consequence; but
from the great interest you have always taken in my brother,
I think it right to mention them. And, with best respects, -I

m,” &c.

The following letter, dated Nairn, 31st October 1814, is
from Miss Mircuett to Mr Parker, and communicates the
complete failure of her attempts to educate her brother by
‘means of the tangible alphabet.

“ Srr,

RESPECTING THE BLIND. AND DEAF BOY. 133.

“ Sir, ya coe!
“ T have from time to time deferred writing you, from a de-
sire rather than from a hope, of being able to give you favour-
able accounts of the result of my endeavours to instruct. my
brother, by the means of letters; and regret excessively being
obliged to state, that I have completely failed in putting into.
effect the plan you so ably sketched out for me, principally,
and, indeed, I may say wholly, from my brother’s wanting the
necessary habits of application. With my first attempts he
seemed rather amused, but afterwards appeared teazed, and got
into bad humour, and, without risking the loss of the little
power I have over him, I could not persist in irritating him,,
being sensible that I only retain it from having recourse to it.
seldom, and using it sparingly. How much I am grieved, at
thus being obliged to relinquish a plan from which so much
benefit might have been derived, I cannot say ; my only con-
solation is, that it is not from any want of exertion on my part.
Had any such plan been commenced with him in infancy; or
at an early period, and steadily persevered in, I doubt not but
it might have had the wished for success; but now, when ‘his
habits are formed, and his passions strong, I much fear there is
little chance of any thing being done; at least if there is any:
thing done, it must be by some person who has more the power
of controlling him than I now have. In short, I am unable to.
make it sufficiently interesting to be a source of amusement to
him, and, as a task, he will not apply to it. Nor is it (how-
ever much to be regretted) astonishing that he will not, accus-
tomed, as he has always been, to follow his own immediate
gratification only, and dispose of his time as inclination leads
him.—Allow me now to’ make offer of our warmest acknow-
ledgments for the benevolent interest you have taken in this
affair, and to assure you, that it will afford us much happiness to
be

134 ADDITIONAL COMMUNICATIONS

be at any time able to show, how sensible we are ea your good-
ness. And I have the honour to sai &e.

In the month of December 1815, I had the pleasure of re-
ceiving a letter from Miss Mrrcuett, from which the follow-
ing is an extract.

“ I cannot say that my brother is making any very visible
progress in knowledge ; but he had a severe illness, about ten
or twelve months ago, which rather placed him in a new point
of view, and I shall endeavour to mention what we considered
as most striking in his conduct. In the first place, he seemed
very apprehensive of dying, at least we could not otherwise ac-
count for many of his actions, than by supposing they proceed-
ed from a fear of death. Although reduced to that state of de-
bility that he could not move without two people supporting
him, we never could prevail with him to lie a single day in
bed; he literally watched the first appearance of dawn, and
insisted on being dressed immediately, thinking, probably,
that he would not die out of bed. Any thing white, too, he
could not. bear to see near his bed, or even in the room with
him. Several times, by accident, something white was thrown
across the foot of his bed, and he appeared most unhappy un-
til it was removed, attempting most eagerly to grasp it himself,
before we discovered the source of his uneasiness. In the
same way, too, when any linens were put to the fire to air by
him, he was in the greatest possible distress until they were ta-
ken out of his sight ; and this, when there was not any glare of
light that could affect him ; it, therefore, must have been some
idea connected with them that distressed him; and from his
having always seen dead bodies laid out in white, we could on-
ly attribute his evident dislike, to his associating the idea of
death and this appearance together. He took a particular fan-

ei,

RESPECTING THE BLIND AND DEAF BOY. 135

cy to a sister of my father’s, who was here at that time, insist-
ing on her sitting constantly by him, (probably from finding
her kind and attentive to him). But I chanced to be taken ill
before he was quite recovered ; and after my being attacked, he
would not allow her to sit down near him, but always signed to
her to go up stairs where I was, and was not satisfied until he
made good his point. This is, perhaps, the most decided in-
stance of affection and consideration for. others, he has ever
shewn. He, once or twice, discovered a: wish to get. up stairs.
himself, and, upon being brought up, seemed quite satisfied:
when I patted him, and shook hands with him.”

9h ei VIL.

Sse wel vole So
iets rite wi og oF

+ puns Aird ue A wii ae i i
“ent ip ine te ri mom ‘hath en ti
: Beaashondinlinccs th

Sane Y viet 8
‘Vas Dray Auth diate 0
"a ye hy ap eee’ Sonceahntectbetls
Cis el IP te Aeneitiens
HEE ER EY On eee fay i ea me
Age: iets anit nin nit aL brie: iv
Raval ney bacwt Ye! oui ey lhvnetentites, eoAkieteray 8
INFO RTI aid rey rn i eh
oe tae er our
CURA SAP tei elses odtterteat om
ee MR
“wel cos thor a pis dt AO Letiipeent egy 6
Be eI CD wiley Bicone .
Bee eee, eet ey ae
Unset eg etter esr ARTA EB gl BO
na mans WU | ype: ‘Bde deeb, Sp ;
‘ Minden Athi heli al<s' Axgidate? ‘ iliasadinatin — j
Sen eee, eee "hg ll kind ol: a

VII. On the Education of James Mrrcnext, the young Man
born Blind and Deaf. By Henry Dewar, M. D. F. B.S.

Epi.
(Read 4th December 1815. )

HE practicability of instructing in any kind of language a

person blind and deaf from infancy seems not to have
occurred to the friends of James Mrrcuetz till suggested by Dr
Gorvon, whose ideas on the subject are contained in Professor
Srewart’s account published in the Transactions of this So-
ciety *. An attempt has been since made to put in prac-
tice a plan for the same purpose, proposed by Mr Par-
xer, an English gentleman who resided for a short time in
Scotland. This consisted in accustoming him to handle the
letters of the alphabet, formed of pieces of wood or paste-
board, when placed together so as to compose different words
significant of tangible objects, and making him handle the
objects in order to learn their meaning. This, however, failed,
in consequence of the unwillingness of the pupil to submit
to the necessary application. For the details, I refer to the
account lately laid before the Society by Dr Gorpvon +, and
particularly to Miss Mrrcwext’s letter to Mr Parker, dated
the 31st of October 1814, sit aa the result of her endea-
— Vor. VIII. P. I. Ss vours,

* See Vol. vii. p. 70. + See the preceding Paper in this Volume.

138 ON THE EDUCATION OF

yours, and containing her own judicious observations on the
subject. ;

The object of the present paper is, to describe a plan which
seems to be exempt from the obstacles attached to that which
has been unsuccessfully tried. It consists chiefly in teaching
the words, and enabling the pupil to use them without taking
the trouble of ‘combining the letters. This is to be done by
providing him, in the first instance, with entire words ready
formed in a permanent state, shewing him their meaning,
teaching him to distinguish them by simple means, and lea-
ving him to find out, at a comparatively late stage, by his own
deliberate observations on their constituent parts, the forms
of the letters, and the use that is made of their various com-
binations.

The manufacture of words may be conducted in the follow-
ing manner. A few sets of metallic types may be procured,
with the letters hollow and reversed, of a size sufficient to serve
as moulds for casting letters in relief, the form of which can
be distinctly perceived by the fingers. A diameter of three-
fourths of an inch will probably serve the purpose. That the
signs taught may not be unnecessarily multiplied, the use of
capitals should be dispensed with, The letters should resemble
written characters, that he may understand those which are fa-
miliarly used in the communications of other persons ; but they
should not run into one another ; they should even be placed
at a greater distance than is done in printed books, that, he
may handle each letter in all directions with facility, and thus
iearn the sooner to analyse his words. The metallic types may
be placed in the order corresponding to the orthography of each
word, in the bottom of a groove, a little deeper than the thick-
ness of the types, and of a diameter just sufficient to admit
them. The groove will then serve as a mould, in which the
word may be formed of plaster of Paris, softened sealing-wax,
flour-paste, or any other convenient plastic substance.

In

|
|

JAMES MITCHELL. 139

In this manner the names of the objects most familiar to
him may be procured in the form of labels resembling paper-
folders. That he may receive a just idea of the positions of
the letters without future correction, the lower margins of the
labels may be distinguished by a slight ledge, and the words
always given him in the right position. The words should be
laid aside in shelves or pigeon-holes, to which he has access.
All those beginning with the same letter should be contained
ina separate division. A more minute arrangement would
probably, in the first instance, be rather troublesome to him.
The advantages of the arrangement made ought rather to be
left for himself to discover, than industriously inculcated.

- The mode in which he should be taught the meaning of the
words consists in making him handle an object, and, at the
same time, the slip containing its name. This is easily done
with such words as coat, shoe, stocking, water, milk, bread, stone,
wall, tree, wood, and knife.
~ Ifhe is left entirely to himself in distinguishing the words,
his mind will fix on any. circumstance that happens to occur to
him, such as their comparative length, or the form and situa-
tion of particular letters which strike his fancy. This sponta-
neous process would have the advantage of being free from any
proceeding unnecessarily dictatorial. But a little direction,
scarcely amounting to a greater degree of it than is implied in
giving him'the words, may be employed, as conducive to regula-
_ rity. His finger, for example, may be guided along the first and
second letter of each word, in the direction in which the pen
moves in writing. It will not be necessary to turn his attention
so particularly to the succeeding letters, till such time as he is
to be made acquainted with a plurality of words coinciding in
the first two. He may be made, for example, to trace the # and
ct s2 the

140 ON THE EDUCATION OF

the o in the word horse, immediately before being brought to
that animal. His attention will not require to be turned to the
r till he is to be made acquainted with such words as house,
home, and hot. In like manner, when he is to be made ac-
quainted with the word horn, coinciding with horse in the first
three letters, his attention will be directed to the fourth. The
first three will probably by that time be so familiar to his
tact as to require but little tracing, on the same principle on
which other persons learn by habit to read syllables and words
without spelling.

He ought to receive in the very beginning a considerable va-
riety of words ; for, though he is not likely to learn many tho-
roughly at once, he will thus have a chance of sooner under-
standing the design with which they are given. A few should
be more particularly forced on his attention; and, as it is by
distinguishing objects which are nearly allied that he will soonest
perceive the utility of language, it would be advisable to direct
his mind, in the first place, to a single class of objects, such as
the articles of food and drink, the names of which might be gi-
ven to him very fully. When he sits at table, the name of each
article may be placed beside it, and opportunities thus allowed
him to practise this species of association. Significant words
may next be appended to other familiar objects which admit of
it. The frequent repetition of these associations is probably a
better method of producing an impression on the memory, than
the exaction of a task which requires exertion of mind. A
deep interest may be excited by making him handle the name
of a favourite object, such as the word milk or bread, a few mi-
nutes before the object itself is given to him. |The association
will thus be aided by the operation of encouraging hope or
pleasing curiosity. This will be both a milder and more effec-
tual expedient, than to make his proficiency the condition of

the

‘

JAMES MITCHELL. 141

the gratification of his wishes, by withholding an object till
such time’ as he can present his teacher with its name. This
last should not be attempted before there is reason to think that
he has acquired some patience of temper, at least not in his
present situation, where he is subjected to no systematic au-
thority ; nor should it in any case be practised till the associa-
tion has been repeated with sufficient frequency to entitle those
around him to expect that he will remember it. It is, however,
by the names of the most favourite objects that his interest
will be soonest secured, and it will always be proper to. shew
peculiar promptitude in understanding and gratifying his wishes
when he is able to make them known by producing the name
of the object which he wants. A little experience of the ad-
vantage arising in this respect from language will create a de-
sire to make similar communications respecting objects of all
kinds. bhi Rg y . r :

- Some would, perhaps, from their’ opinions on the theory of
grammar, reckon it most correct to teach him in the first. in-
stance substantives alone. But it will be attended with great
advantage to teach the adjectives almost equally soon. They:
may be learned with the same facility ; and they will prove to
him interesting, as affording expressions for his:more general,
and what have been sometimes called moveable ideas. They
will also assist in making him perceive in less time the inten-
tions of the lessons given to him. He may be made to touch
‘one vessel, and at the same time the words warm water, and
another vessel while he touches the words cold water ; and in the
same manner proceed to learn the meaning of such: combina-
tions as warm tea, cold tea, sweet tea, weak tea, strong tea ; hea-
vy stone, light stone, large stone, small stone, and others of simi-
lar application. It would be advisable to give him a separate
set of shelves or pigeon-holes for containing the adjectives, or
to distinguish them by some peculiar mark.

He

142 ON THE EDUCATION OF

He may afterwards learn words of more general import,
and those which characterise temporary relations. One stone
may be placed on his knee, or close to him on a table, while
he handles the words ¢his stone ; another at a greater distance,
while he handles the words that stone. He may also learn va-
rious gradations of qualities, as cold, temperate, warm, hot, very
hot. His lively and intelligent turn of mind affords a hope that
words of all kinds may be effectually explained to him by
well-marked and varied exemplifications of their use.

The chiefdifficulty will be, to make him understand the in-
tentions of his friends in following these measures, and to im-
press him with their utility. All the difference, however, that
exists between him and other persons, in this particular, con-
sists in the smaller number of lessons that can be given to him
in the same space of time. No essential medium of com-
munication is wanting. It is only by observing a number of
motions, and hearing a number of vocal sounds in themselves
unmeaning, and perceiving the association of them with the oc-
casions on which they habitually occur, that children perceive
the intention of human language. They enjoy the great ad-
vantage of having the materials of it, in their various connec-
tions, perpetually offered to their notice. Jamzs Mircuett is
entirely dependent on the instructions given to him intention-
ally, and with considerable labour, by other persons; and his
progress, in the first instance, must be proportionally slower,
as the number of instructive impressions made on him in any
interval of time must be smaller. Some advantage in compen-
sation of this will be derived from the greater maturity of his
natural powers. Yet we must be aware that some disadvan-
tage will arise from the comparatively fixed state of his habits.
If the first difficulties are once surmounted, there is every pro-
bability that he will perceive the utility of language in opening

to

JAMES MITCHELL. 143

to him new sources of agreeable knowledge, and will then
make voluntary exertions to instruct himself by engaging in so-
litary lessons, or by soliciting in particular instances information
from those around him. , ;

Tt is after he has, on this plan, made considerable progress,
that success may be expected in teaching him the useof the
separate letters.. For this purpose, letters formed with the
same types may be given to him in a drawer of twenty-four di-
visions, in alphabetical order. By means of these, his familiar
words may be frequently formed for him in his presence, and
he may gradually learn to form them for himself... There will,
however, be no propriety in urging this part of instruction with
much earnestness. If he shows himself in any degree reluc-
_ tant to it, his teacher may be content with giving him farther
instructions in prosecution of the first part of. the plan. In
addition to such instructions, it will be sufficient to give him,
in the first instance, an opportunity of forming words for him-
self when he is inclined. By being first made a complete mas-
ter in one department, he will be prepared to make more
rapid progress in another.

_ Till he has made considerable proficiency in the knowledge
of entire words, and acquired a relish for language, any further
expedients are comparatively of little interest. But, anticipat-
ing success in this part of the undertaking, the execution of
which must be regarded as the most difficult, I proceed to
describe some subsequent expedients. These will evidently

admit of being greatly varied cteending to unforeseen ‘circum-
stances.

If it is fons shit, after having itch the use. Bu entire
Bahn he cannot be easily taught to combine the letters, it will
be proper to increase his stock of words. Other parts of
speech besides substantives and adjectives may now be given

‘ to

144 ON THE EDUCATION OF

to him. Verbs.of motion and of posture will be easily taught,
and rendered interesting by being associated with the mo-
tions and postures which they denote. Such are the words
walk, run, strike, break, eat, drink, lie, sleep. The words ts
and not will prove extensively useful, by enabling him to con-
nect, in the form of sentences, his substantives and his adjec-
tives. He should also be provided with some significant ter-
minations, particularly the letter s and the syllable es, which
may, on proper occasions, be attached by some easy expedi-
ent to the labels containing his other words. It will be very
easy to show him the difference between stone and stones, cup
and cups, dish and dishes. The use of the terminations ed and
ing, and a variety of others, will naturally follow in the order
of their relative importance.

If he can be brought thus far, the rudiments of connected
discourse will gradually accumulate; but the process requires
to be conducted by a person who has sufficient discrimination
to introduce no words except such as correspond to the limited
knowledge admitted by the senses of which he is possessed.
Such short sentences as the following may first be taught him:
This water is warm; that water is cold; it rains ; it blows hard ;
go to the house; take off your clothes ; we must go to sleep.

After he is well advanced, he may be furnished with some
sort of horn-book to facilitate his communications. Perhaps
the best form for this purpose would be a glove, with the —
letters in relief attached to it; the vowels being placed on the
tips, and the consonants under them, in alphabetical order,
on the bones and joints of the fingers. This will insensibly
conduct him to the practice of a convenient dactylology, and
he will in no long time be able to converse with his friends by
the fingers, without the use of the glove. With a view to this

‘acquisition,

JAMES MITCHELL. 145

acquisition, his alphabet may, from the very beginning, be ar-
ranged in lines corresponding to the following order :

Xo fos
a Shin
sz west.o.
soe sight Oo
XR Sse Ge

A subsequent stage of instruction will be, to send messages
to him, which may be impressed on surfaces of wax, and in-
duce him to return answers, or to send other messages.

Perhaps the art invented by Mons. Havy for the use of the
blind may be found convenient for such purposes, that of im-
pressing the letters with direct types on strong paper in a
moistened state, so as to give tangible letters in bold relief on
the opposite side. Not having seen any of the articles produ-
ced by this manufacture, I cannot give an opinion on the ex-
tent of its utility as applied to the present object; but hard

~ casts are probably better fitted to insure success at an early

stage of the process, as they are not liable to be injured by fre-

quent handling.

The teaching of the numbers is a separate object, but com-
paratively easy, and may be conducted in such a manner as to
prove amusing both to him and to his teacher. It should be
done entirely by means of our common ciphers, without. the
use of words. To a person in his circumstances.the names of
the numbers in letters would be of no use; and it is easy for
every person who afterwards.converses with him to employ
ciphers exclusively. - This rule, with the omission of the use
of capital letters, ‘as already mentioned, would form only two
peculiarities in his language, easily followed by his friends.

Vox. VIL. P. 1. wae Es AAMAS Ee The

¢

146 ON THE EDUCATION OF

The numbers may be as easily taught as any other adjec-
tives, and on exacily the same principles. Each mark is, in-
deed, significant, which is not usually the case with the letters
of which words consist. But this circumstance cannot produce
any embarrassment. When he knows the meaning of the
werd cup, that of 2 cups and 3 cups is easily conveyed ;
and the variation of the examples will soon suggest the gene-
rality which is to be attached to the numerical sign. The mean-
ing of the units and their combinations may be taught by
means of small bodies, such as pins, marbles, or pebbles.
The regularity of the decimal numeration, and the power of
expression obtained by the combination of the ciphers, are
not unlikely to be contemplated by him with considerable re-
lish.. Information in these particulars may at first be conveyed
to him by means of pins stuck in a flat cushion, or pegs
stuck in holes in a board, in such an order as the following :

] ‘
byuages
&e.
10 Se eee ede cl he te Sin abo
Bs As akoptvngiontine ad, weasel |
&e. f
20. 31-4 iain nh Pasi 28h
« &e

100 e ° . . . ° . . . .

The

JAMES MITCHELL. 147

The extent of arithmetical instruction which it will be proper
to give him must depend on the degree of zeal and intelli-
gence which he displays in the progress of his lessons. Limit-
ed as the objects are which solicit his curiosity, he may disco-
ver in arithmetic, geometry, or some other science, a degree of
application, and acquire a degree of proficiency, which to the
greater part of men would appear miraculous. This would un-
doubtedly be highly interesting ; but it is evident that no par-
ticular anticipations on the subject can be cherished.

That he may be enabled to trace minutely the lapse of time,
he should have access to examine the dial-plate of a clock with
the hours marked with common ciphers in relief; or a watch
should be given to him with a dial-plate formed in that man-
ner. This piece of instruction may easily be conveyed in-
dependently of any other, and the exercise is likely to im-
prove the regularity of his: habits.

If these and) a variety of similar expedients are attend-
ed with the desired success, trials will naturally be made to re-
duce, for the sake of convenience, the size of all his characters.
When they are near the minimum, he will now be able to make
the circumstance distinctly known. _ As soon as the most eli-
gible size is discovered, a simple printing-press may be provid-
ed for him, which will serve the same purpose which pen and
ink do to:others, and his friends may use it for furnishing him
with pages of interesting anecdotes or instructive lessons, to
occupy occasionally his moments of solitude.

In his communications with others, it will not long be ne-
cessary for him to employ tangible letters. He will find, that with
certain materials he can write’ words which, though not pal-
pable to himself; are understood by others. By making this

HIT oh (Re -. discovery,

148 ON THE EDUCATION OF

discovery, he will learn somewhat more particularly the nature
of the advantages which the sense of sight confers. This is to
a blind man an interesting article in the natural history of his
species.

If he could be brought thus far, much additional improve-
ment would soon follow. If, on the contrary, his want of ap-
plication, or habits already too deeply fixed, should render him
incapable of learning so much, it is evident that a degree of
communication cinonighgasle short of this would be to bite au
most valuable acquisition. The probability is, that, after a little
time, he will take the same delight in prosecuting his educa-
tion which a child does in learning to understand what is said,
and to make use of language.

It is by giving an sags to his ardour, and thus Sitios
his will, that any person will be able to give to his mind, which
is apparently desultory, a regular direction to a valuable object.
His present unwillingness to submit to the dictates of other
persons is a feature of mind which he possesses in common
with a great proportion of mankind. Many individuals who
had disdained the discipline of a school in early life, and ap-
peared inferior to all their cotemporaries, have afterwards, to
the great surprise of those whose views of human nature were
superficial, acquired the highest proficiency in a branch of know-
ledge which had accidentally attracted their interest, or have be-
gun to prosecute literature and science in an order suggested by
their own thoughts, and rendered themselves illustrious as uni-
versal scholars. Some of these singular features of character, as
well as that degree of indifference which is much more com-
mon, have been produced by the injudiciousness and forma-
lity of the prevalent methods of education. It is by the appli-
cation of a more considerate policy to the developement of the
human powers that we are to expect to communicate most ef-

fectually

JAMES MITCHELL. 149

fectually to persons of various natural faculties and various dis-
positions the benefits of education. Principles analogous to
those which have been recently introduced into schools will.
afford great assistance in the education of James Mrrcuett ;
_and the study of such an interesting and difficult case as his,
together with the various incidents which must arise in the
execution of a carefully concerted plan, may throw some light
on that sort of management which is required both for domes-
tic tuition and for the universal interests of education.

' Miss Mircuexx’s letter to Mr Parxer*, giving an account of
the failure of her efforts, shews the necessity of method as well
as of delicacy in-the undertaking. A plan which imposes less:
labour on him, and leaves more to his own activity as excited:
by powerful motives, will be so far in less danger of producing
disgust. Although his present local situation were not altered,
I should entertain some hopes of success from the plan which
I have described, in the hands of Miss Mrrcnerr. But, if
these should be disappointed, the object might with certainty
be attained by a change of measures not difficult of execution.
Miss Mircnerx allows that another person, possessing more:
controul over her brother’s mind, might succeed better than
she did, and thus shows that she did not suffer the temporary
disappointment to produce irrational discouragement. Before
reading this letter, we might naturally enough consider her:
presence as necessary to his comfort and improvement. But
it now appears evident that the plan of instructing him in
language would be commenced with greater advantage by a
temporary separation, provided he were connected with” an:
establishment otherwise suitable. He should be under the.
care of a stranger, who has a perfect understanding of the~
mode of conducting his lessons, and who would carry it into:
effect’ by an authority from which there would lie no ap-.

peal.
* See p. 130. of this Volume.

150 ON THE EDUCATION OF

peal. In such a situation, he might also be favourably af-
fected by the novelty of finding every surrounding object ac-
companied by a label, of which he would be provided with a
duplicate. The discipline employed must be steady ; but there
is no occasion for harshness. Although he has hitherto been
suffered to follow the impulse of his own wishes, it will be re-
membered that in one instance a mild and decisive step was
taken to deter him from exposing himself to danger *. He was
observed creeping over a narrow wooden bridge which crossed
a river at a point where the stream was deep and rapid; and,
that he might not again make the same hazardous attempt, a
servant was directed to plunge him, as soon as he was secured,
once or twice into the river. This expedient had the desired
effect. All the discipline required would partake of this
character, and would only differ in being dictated by a regard
for his improvement, and not by any apprehension for the
safety of his life. The disappointment of his habitual expec-
tations of indulgence, and the passion or chagrin which this
would at first occasion, should not be considered as any greater
obstacles to perseverance than in proceeding with the domestic
controul of children. Miss Mrrcnexu’s influence over him is
highly reputable to her, as showing her dexterity in kindness
under circumstances of difficulty ; but it would be an object
of some importance to make him easily manageable by other
persons. There is every reason to think that, by a very short
separation and subjection to well-concerted rules, he would, on
returning to the society of his friends, find himself much hap-
pier than before, and capable of giving them more pleasure,
and that it would afford him great delight to find that his sis-
ter understood the language which he had learned, and could
maintain with him intelligent communications. Tinding him-
self now of greater importance in the scale of society, and pos-

sessing

* See Vol. vii. p. 27.

' JAMES MITCHELL. TSl

sessing a more accurate knowledge of the occupations and ha-
bits of others, he would probably acquire practical patience, and
accommodate himself more completely to the convenience of
those around him.

One of the most promising advantages likely to be conferred
on him by the acquisition of language consists in the opportu-
nity afforded to his friends to make known to him the utility
of an operation for the cataract. It would now be indispensa-
ble to obtain his: consent before proceeding to any operation.
‘The employment of force would be equally unjustifiable as in
the case of any other adult. If he is reluctant, the operation
ought to be delayed, and, in the mean time, easy experiments
employed, and advantage taken of accidental occurrences, to
impress on him the wisdom of submitting to temporary pain
for the sake of important subsequent advantages.

To some it might appear probable that this young man,
from beginning to learn language comparatively late in life,
would be the better enabled to gratify philosophical i inquirers
with a comparison between the state of his ideas before and af-
ter making that acquisition. On this subject, however, they
ought not to entertain very sanguine hopes. Our past impres-
sions, especially in their defective points, soon cease to be dis-
tinctly traced. The only exceptions to this general fact are
those crude ideas of an inexperienced age which give amuse-
‘ment on recollection by their grotesque and incongruous cha-
acter. The most prominent revolutions of his mind would
probably affect the ideas which he entertains of the habits and
sentiments. of other persons. A statement of his views as in
this respect. improved, though it might be considered as little
fitted to elucidate the more recondite doctrines of pneumatolo-
gy, could not fail to prove interesting to all who take pleasure
in the study of human nature.

- APPENDIX.

152 ON THE EDUCATION OF

APPENDIX.

17th June 1816.

It is only within this fortnight that any preparations have
been made for the prosecution of the plan described in the
preceding paper, and they would not have been mentioned in
their present imperfect state, were it not that this is the last
meeting of the Society for the season. All the experiments made
have consisted in attempts to find out the most eligible method
of providing tangible words, a point which must be fixed upon
before the plan is communicated to those on whose care the
execution of it is ultimately to devolve.

Moulds of wood and of lead have been tried, and a specimen
of a word formed in plaster of Paris from a set of leaden
moulds is here shown to the Society. After various trials, the
size of letter fixed upon is nearly that exhibited in the wooden
cut accompanying these observations. It is found that a
greater degree of distinctness to the sense of touch is gained by
placing the strokes at a considerable distance from one another,
than by increasing the perpendicular depth of the letters. A
eharacter similar to what is called a round hand in writing,
though not easily made elegant on a large scale, is therefore
the best adapted to the present purpose. It is evident from
the specimen now produced, that plaster of Paris is objection-
able for its brittleness and weight, as well as the expence and
trouble connected with it. Some of these objections lie also
against wax, clay, and paste. Letters formed of paper or
thin pasteboard, on a plan similar to that of Hauy already
mentioned *, will be far more suitable, and, from two specimens
now laid thats the Society, it will be seen that they are
sufficiently palpable, sufficiently strong, and also very eco-

nomical.

* Page 145,

JAMES MITCHELL. 153

nomical. Both were formed from hollow moulds. The
pasteboard was first moistened, then laid on the mould. In
making the one, a layer of fine sand was placed above it,
and over that the weight intended to produce the impression.
In making the other, the thin pasteboard was carefully forced
into the hollow lines of the mould with a paper-folder ; small
quantities of moist paper were then stuffed into the cavity to
fill it, and over this the weight was laid till it was dried. A
subsequent improvement has occurred, for which I am in-
debted to the ingenuity of Mr Joun Rursven (the inventor
of the Ruthven printing-press), who is now executing in brass
a set of types adapted to this object. This consists in form-
ing hollow moulds, of the size and shape of letter now fixed
upon, and also letters in relief corresponding to them, by which
the moistened paper or pasteboard may be forced into the
moulds. This method produces an impression in a most cor-
rect and speedy manner, and any word in one entire piece
may be conveniently formed. The nature of these materials
: is such as to enable any person, when in possession of sepa-
rate letters, to fix them together extemporaneously, so as to
form words which can either be kept in that state or taken to
pieces at pleasure. The separate letters may be introduced in
their proper order into a running case formed of paper or
pasteboard, and the word will then have this appearance.

|

Vou. VII. P.I. U This

}
y
¢
i

154 ON THE EDUCATION OF

This figure represents a slip of pasteboard, which has two
narrow slips stitched to it, the ‘one along its superior, and the
other along its inferior margin, so as to admit the letters to be
introduced under their edges, and held in their places. The
hole at the beginning of the word serves for fastening a loop
by which it may be suspended ; it also serves as a mark for
the beginning of the word, and thus directs the pupil in the me-
thod of holding it correctly. A page of pasteboard, consisting
of a succession of lines formed in this manner, will be a con-
venient surface for containing tangible sentences, instead of
the surface of wax formerly mentioned *. The letters are here
placed at a considerable distance, which will be proper in the
first instance, that their forms may be separately traced. It
will afterwards be easy to cut off the superfluous paper from
each, to bring them nearer together, and thus save space +.

It is one great advantage of the preceding plan that it may
be executed at very little expence. If it succeeds in his pre-
sent situation, the expence will be a mere trifle. If not, a si-
tuation in the country will still be the best adapted to him.
Any intelligent person possessed of sufficient leisure, (a coun-
try clergyman for example,) might, by having him for a cer-
tain time an inmate of his house, execute the whole with
little difficulty. All the expence would consist in a suitable
board for twelve, or perhaps only for six months. For pro-
viding this, there certainly will be no necessity for having re-
course to any steps which the manners and feelings of our

country

* Page 145.

++ This plan is evidently adapted to the use of the blind in general ; and experi-
ments may be made with great facility on that class of persons, whose claims
on the attentions of society are fully recognised, though they are highly pri-
vileged when compared with the subject of these observations. Such experi-
ments, it is to be hoped, will be speedily attempted, if they have not hitherto
been made.

Y
|
|
|
:

JAMES MITCHELL. 155

country render exceptionable. There are undoubtedly indi-
viduals ready to expend much more in philosophical experi-
ments of a less interesting kind, who, if confident of success,
would be happy to have an opportunity of offering, in this in-.
stance, a tribute to science. I hope that some experiments
will soon be made by Miss Mrrcnetz, on the plan now de-
scribed, assisted by such observations as occur to different
gentlemen who are friendly to the undertaking. If these
should fail, it is still to be hoped that the object will not be
lost for want of further efforts.

The utility of it is not limited to one individual. It has
been justly remarked that other parallel cases have very pro-
bably occurred, which, from a false delicacy, have been con-
cealed from general notice. Accounts have lately been recei-
ved of one now existing in the United States of America.
It will be highly pleasing to find that two individuals so far
removed from the rest of mankind in their present means of
communication can be taught the same language, and enabled
to compare together the ideas which they have acquired rela-
tive to themselves, to the world in which they dwell, and to
the rest of mankind, who must roy, to them intelligences of
a superior order.

We feel sensations allied to compassion when we contem-
plate their situation. Part of this, however, arises from the in-
fluence of a comparison with our own advantages, which we
are too apt to consider rather as necessary to our being than as
contributing to our enjoyment. The scale of Pappinead' is not
regulated by the degree of these advantages ; and, instead of
deteriorating the hearts of these individuals by officiously
teaching them to mourn over their misfortunes, we shall be
better employed in collecting for our own use materials to-
wards the cultivation of the art of happiness, by observing that

U2 serene

156 ON THE EDUCATION OF JAMES MITCHELL.

serene contentment which, when not corrupted by other per-
sons, both the blind and the deaf so often exhibit. When the
blind are addicted to complaints on this subject, it entirely
arises from the superfluous lamentations which they hear from
those around them. This occasionally exists in circles in
which a sickly and unprofitable sensibility is cherished ; but it

chiefly abounds among persons who are indigent and neglect- .

ed, and who indulge in the habit of bewailing their fate as a
part of the talent of the mendicant. In these particulars no de-
ficiency of manliness seems to have been betrayed by James
Mircuett, though his privations are doubled; and, as he ad-
vances in his intercourse with others, he is not likely to receive
his impressions in a school in which any feelings tending to
generate depression will be fostered. The glimmerings which
he receives of his own state by a comparison with the advan-
tages of others will add to his stock of information, and will
contribute to render him more reasonable, without producing
any mortification of his feelings. He must find himself always
dependent on others ; but in this there is nothing to render
the mind abject. Every man is dependent on the arrangements
of nature and of society; and that species of erectness and
fancied independence which arises from a forgetfulness of the
condition of man is rather to be condemned as a poor and ig-
norant pride, than regarded as a valuable prerogative accom-
panying the possession of external advantages.

VIII.

VIII. On the Optical Properties of Muriate of Soda. Fluate of
Lime, and the Diamond, as exhibited in their action
upon Polarised Light. By Davw Brewster, LL. D..
F.R.S. Lonp. & Epiw. & F. A. S. Enin,,

[Read Nov. 20. 1815.]

WT has long ago been remarked by the Abbé Havy, that’ the
i property of Double Refraction is not possessed by any of those
crystals the form of whose integrant molecule is distinguished
by its symmetry, such as the Cube and the Regular Tetraedron.
_ This class of minerals comprehends Fluate of Lime, Muriate of
Soda, Spinelle Ruby, Muriate of Ammonia, Alum, and the Dia-
mond; and though M. Havy had examined only a very small
number of doubly refracting crystals, yet, with the exception
of the Diamond, which I have found in many cases to possess
the property of Double Refraction, his remark was confirmed
by the experiments of Matus, Bror and myself, who consider-
ed all the crystals of this class as exercising no more action

upon polarised light than a mass of water.
No explanation was offered of this singular anomaly, till
M. Bior discovered that all doubly refracting crystals are
divisible

158 ON THE OPTICAL PROPERTIES OF MURIATE OF SODA,

divisible into two classes ; one of which is represented by cal-
careous-spar, and the other by rock-crystal. M. Dr La Pracz *
had already shewn, in his fine theory of Double Refraction,
that all the phenomena of calcareous-spar could be explained
by supposing the deviation of the extraordinary ray to be pro-
duced by a repulsive force, directed from the axis, and propor-
tional to the square of the sine of the angle which the extraor-
dinarily refracted ray forms with the axis of the crystal. In
like manner, M. Bror perceived that the phenomena of double
refraction in rock crystal were explicable by an attractive force
directed to the axis of the crystal, and following the same
law; and he was led to suppose, that muriate of soda, and
fluate of lime, &c. composed an intermediate class of crystals,
in which there was neither an attractive nor a repulsive force,
and consequently neither a division nor a polarisation of the
transmitted pencil.

In this state of the subject, Philosophers will no doubt be
surprised to learn, that muriate of soda, fluate of lime, the
Diamond, Alum, and probably all other crystals of the same
class, have actually the property of Double Refraction, but
under circumstances of such a singular kind, as to entitle
them to be regarded as a new class of doubly refracting crys-
tals. ;

The specimens of fluor-spar in which I first recognised this
property, are represented in Plate IV. Figs. 1, and 2. and had
the following dimensions :

Fig. 1. Fig. 2.
AB = 1.03 inches, AB = 0.80
AC = 0.6 ACir= 0.3, _
AD = 0.6 AD = 1.0

Both

* Sur la lot de la Refraction extraordinaire dans les cristaux diaphanes. Mém,
de l'Institut, 1609.

FLUATE OF LIME, AND THE DIAMOND. 159

Both of these crystals seemed to inclose a number of cubes
of different tints, having their faces parallel to the external
cube.

When polarised light was transmitted through the faces
ADC, BEG, it was distinctly depolarised, the neutral axes AD,
AC being coincident with the sides, and the depolarising axes
AE, DC with the diagonals of the square faces ; and, what
was still more remarkable, in all the specimens there were
portions of the crystal where the polarised light suffered no
change. In these experiments, the tint polarised by the
spar was a blue of the first order, having a pale red for its
complementary colour.

In order to examine the tints with more correctness, I com-.
bined the cube of fluor-spar with a plate of sulphate of lime,
which polarised a brilliant blue of the second order, having an
orange-yellow for its opposite colour. The blue was changed
into a scarlet-red, and sometimes into a purple-red, and the
complementary orange-yellow into a yellowish-white. When
the cube was turned 90° round, the b/we was changed into a
pale yellow-green, and the complementary orange-yellow into a
yellowish-purple.

This change of colour was consonant to the Jaws which regu-
late the action of all crystals upon light ; but I was surprised
to observe, that when the cube of fluor-spar remained station-
ary, there was one portion of it at m, Fig. 3. which made the
blue colour red, and the orange-yellow a yellowish-white, while
another portion, at n, made the blue colour green, and the
orange-yellow, purple. In another specimen, I found the same
opposition in the effects produced by two different portions,
m, 0, which were separated by a third portion that had no ac-
tion upon light, the part o producing the same effect that
m would have done when turned 90° round, and m the same

effect

160 ON THE OPTICAL PROPERTIES OF MURIATE OF SODA,

effect as o when turned 90° round. The preceding phenome-
na were exhibited in every specimen that had a considerable
thickness.

My experiments on muriate of soda were made with large
masses of various sizes, from half an inch to three inches in
length. They all exhibited the same properties as fluor-spar,
the depolarising axes being coincident with the diagonals of
the square faces, and the neutral axes with their sides. In the
largest pieces, the polarised tint was a fine blue, with a pale
yellow for its complementary colour, and the oppositely pola-
rised portions produced by different parts of the mass, were
arranged in streaks parallel to one of the diagonals AC of the
cubical face ABCD, as represented in Fig. 4. Similar pheno-
mena were exhibited in large pieces of transparent alum.

In my first experiments on the Diamond *, the spe-
cimens which I employed had very uneven surfaces; but I
have lately repeated them with nine flat diamonds, for which
I was indebted to Joun Rosison, Esq. Almost all these spe-
cimens depolarised the light in separate spots, of an irregu-
lar shape, and the depolarising portions had opposite struc-
tures, like the specimens of muriate of soda and fluor-spar
which have already been described. The appearance of these
diamonds, when exposed to polarised light, is represented in
Fig. 5. One of them, however, had a more perfect crystalli-
sation, and exhibited four parallel fringes, as shewn in Fig. 6.
The tints were a white of the first order. When the inte-
rior fringes ofa plate of crystallised glass were held paral-
lel to the fringes a d, cf, the difference of their effects was pro-

duced,

* See Phil. Trans. 1815, p. 29.

‘FLUATE OF LIME, AND THE DIAMOND. 161

‘duced, but when the same fringes were held parallel to the
fringe be, the sum of their -effects was produced. Hence it
follows, that the structure which produces the fringes a d, cf,
is the same as that of one class of doubly refracting crystals,
and the structure which produces the fringe 4e, the same as
that of the other class. An effect exactly similar to what is
shewn in Fig. 5. is exhibited by the sclerotic coat in the eyes
of fishes, and may be produced by crushing a piece of soft
isinglass, or by pressing a mixture of rosin and bees-wax *,
‘between two plates of glass.

The preceding experiments entitle us to conclude, that mu-
riate of soda, fluor-spar and the diamond, combine in the same
specimen three different structures, and form a new class of
doubly retracting crystals. In some parts they act upon light
dike that class of crystals in which the deviation of the ex-
traordinary ray is supposed to be produced by an attractive
force. In other parts they act upon light like the other class
of crystals in which the extraordinary ray deviates from the
axis in virtue of a repulsive force; and in intermediate por-
tions they exhibit that mean structure, in which the light is
urged neither by attraction nor repulsion, and where there is
neither a polarisation nor a division of the transmitted pen-
cil. If the laws which regulate the crystallisation of these
minerals had been allowed an undisturbed operation, it is pro-
bable that the crystals would have had a perfect cube or an
octahedron for their primitive form, and would have exhibited
none of the phenomena of double refraction.

The slightest irregularity, however, in the operation of these
jaws, would produce a deviation from the perfect primitive
form, and the crystal would therefore deviate from the inter-
mediate class into the attractive and repulsive classes, and

Vou. VIII. P. 1. x would

* See Phil. Trans. 1815, p. 32, 33.; and 1816, p. 172, 173.

162 ON THE OPTICAL PROPERTIES OF MURIATE OF SODA,

would thus acquire the three different structures which we
have actually found it to possess.

If this view of the subject be correct, it will follow, that the
cubical and octahedral forms are intermediate between those
which belong to the attractive and repulsive classes of doubly
refracting crystals ;—that a deviation from these forms on one
side will produce the structure of the attractive class, and a de-
viation on the other side the structure of the repulsive class ;
—that the force of double refraction increases with that devi-
ation, and that there is a certain primitive structure belonging
to each mineral, by which its class may be ascertained.

The imperfect state of crystallography does not enable us to
determine what this structure is; but when this science shall
have made farther progress, we may probably be able to
ascertain from the crystalline forms of minerals, both the cha-
racter and the intensity of their doubly refracting force.

APPENDIX.

Edinburgh, July 4. 1816.

M. Brot, who had an opportunity of examining the greater
part of the preceding paper in MS. in October 1815, has sta-
ted in his Traité de Physique, tom. iv. p. 573, newly pub-
lished, that the polarising structure which I have discovered in
Muriate of Soda, Fluate of Lime, and the Diamond, appears
to be owing either to the effects of heat, or rapid evaporation.
“ C'est je crois 4 cela,” says this eminent mathematician,
“ qu il faut attribuer les indices de polarisation observées acci-

“ dentellement par M. Brewster dans certains echantillons de
“ cristaux

FLUATE OF LIME, AND THE DIAMOND. 163

“ cristaux qui par leur nature ne possedent. point la double re-
“ fraction. Enfin ce qui achéve de confirmer, cette maniére
“ de voir, M. Brewsrer a encore imprimé les mémes proprie-
“ tés, des plaques de gelée animale, en exercant sur elles ex-
terieurement une pression passagere ; de sorte que les cou-
“ leurs paraissent tant que la pr Pani Gms dure, varient avec elle,
* et, evanouissent quand elle cesse.’

Had M. Biot repeated the experiments to which he alludes
in the preceding passage, and compared the results with those
produced. by heat and) rapid evaporation, he would have in-
stantly seen that the two classes of phenomena are essentially
distinct, and.could. not possibly have the same origin. In the
polarising structure produced by heat, by rapid cooling, and by
evaporation, the.axes are constantly related to the edges, the

al

i 4

angles and the surfaces of the bodies which are employed, and

the nature and form of the optical figure which they exhibit,
depend solely on the outline and on the thickness of the mass.
In cubical and octahedral crystals, on the contrary, the polarising
axes are related to the axes of the crystals themselves, and have
no connection whatever with the shape or outline of the mineral.
If we take a cube of muriate of soda, for example, which has
not sufficient thickness for developing its structure, and expose

_ it either to heat or pressure, we shall find it impossible to ap-

ply either of these powers in such a manner as to produce a
crystallisation that has the smallest resemblance to the effect
shewn in Plate IV. fig. 4. If the muriate of soda is thick
enough to render its structure visible, then the crystallisation

superinduced by heat or pressure may be seen at the same

time with its own natural crystallization. The results obtained
by means of the diamond, as shewn in fig. 6. and with which
M. Bior was not acquainted when he wrote the preceding pas-

X 2 : sage,

164 ON THE OPTICAL PROPERTIES OF MURIATE OF SODA, &c.

sage, shew still more satisfactorily the difference between the
two classes of phenomena. .

I do not understand what M. Bror means by saying, that
these discoveries were made by accident, (“ observées accidentel-
“ Jement dans certains echantillons’’); for all the results in the pre-
ceding paper were obtained in the course of a regular train of ex-
periments, undertaken for the express purpose of examining
this anomalous class of crystallised bodies; and the polarising
structure was detected, not in some specimens, but in every
specimen of a proper thickness which I had an opportunity of
trying.

In my experiments on Animal Jellies, I had repeated oppor-
tunities of observing, that a polarising structure, invisible in a
single mass, could be rendered perceptible by an augmentation
of thickness ; and I was naturally led to suspect, that a similar:
result would be obtained by using large masses of muriate of
soda, and fluor-spar, although, like M. Matus and M. Biot,
T had sought for it in vain in ordinary specimens.. rita

TX.

PLATE Iv

Engraved for the Rayal Society Tran* Volt Page 164

by ic * 4 .
ee ®. ers

Cpt ah

IX. Ona New Optical and Mineralogical Property of Calca-
reous Spar. By Davin Brewster, LL. D. F. BR. S:.
Lonp. & Enry. F. A. S. Epi.

[Read April 30. 1816.]

T has been long known to those’'who have studied the opti--
cal properties of Calcareous Spar, that there are numerous:
specimens of that mineral which form a multiplicity of images,.
affected with the most brilliant colours. These colours were:
considered by Matvs, and other philosophers, as the colours:
of thin plates, and were supposed to be produced by a film of
air, included in accidental fissures or fractures within the crys-
tal. I have already shewn*, from numerous experiments, that
this opinion is erroneous, and that the various. colours with
which the images are affected, arise from the transmission of
polarised light, through: an. extremely thin film or stratum of
calcareous spar, which has different thicknesses in different
specimens, but which has an invariable position, being always’
parallel to a plane passing through the longer diagonals of the
rhomboidal faces. —

Since that paper was written I have obtained some very per-
fect specimens of calcareous spar, which have enabled’ me to:
obtain several new and interesting results. One of these speci--

mens:

* See Phil. Trans, 1815, p. 270.

166 ON A NEW OPTICAL AND MINERALOGICAL PROPERTY

mens is represented in Plate IV. Fig. 7. where ABC is the great-
er angle of the rhomboidal face, and abcd the interrupting
stratum or film of calcareous-spar. Now, if ABCD were a com-
mon specimen of calcareous-spar, a ray of light incident upon
either of the faces aBFd and JBFc, and transmitted through
the face ADHE, would be separated into two pencils; and if
these two pencils were received upon another prism of spar,
four pencils would be formed, and two of them would vanish
at every quarter of a revolution of the second prism. In the
preceding specimen, however, when a ray of light is incident
upon aBEd, or DBF c, and transmitted Leiuohie ADHE, it is
divided into two pencils; but these pencils ave suffered such a
change in passing through the stratum abcd, that when they
are received upon a spetiall prism of common calcareous-spar,
none of them will vanish in any position of the second prism, but
will continue visible during the whole of its revolution. But if
the ray of light is first incident on the surface ADHE, and
emerges from aBFd, or bBFc, it possesses the same properties
as if it had passed through the common specimens of calca-
reous spar.

The phenomena now described, are exhibited in every spe-
cimen of calcareous spar with an interrupting stratum, and cut
in the manner shewn in Fig. 7.; and though they appear at
first sight very perplexing, yet they are capable of the most
satisfactory explanation. They are visible only when the in-
terrupting stratum abcd intervenes between a prism abBceFd
and a flat plate ADHbdcdE; for when the stratum is interposed
between two prisms, the multiplication of i images takes pi
as described in the paper already referred to.

The interrupting stratum a dc d, is crystallised in a different
manner from the rest of the rhomboid; that is, its. axes are
not placed symmetrically with those of the mass which in-

closes

ee

—-

OF CALCAREOUS SPAR. 167

closes it ; and from this circumstance arise all the phenomena
we have mentioned. When a ray enters the surface BFda, or
BF cd, it is divided into two pencils, polarised in opposite planes ;
and when these two pencils reach the interrupting stratum
abcd, they are depolarised by that stratum, in the same manner
as if they had been acted upon by a film of sulphate of lime, and
each pencil consists of two pencils, oppositely polarised, but not
separated from each other. These two compound pencils have
their polarisation again changed, by the flat plate ADdcdE;
but as it cannot separate the oppositely polarised portions, the
two pencils emerge from the face ADHE in such a confused
state, that none of the four pencils into which they are subdivi-
ded by the application of asecond prism, can vanish in any part
of its revolution.. Henee, the reason is obvious, why the pen-
cils vanish when the ray of light is first incident upon the face
ADHE;; for in this case, the compound pencils, when trans-
mitted through the stratum abcd, have their opposite polar-
ised portions arranged into two pencils, polarised in an oppo-
site manner, by the action of the prism BadcFd.

Let us now endeavour to determine what is the position of
the axes of the film relative to those of the surrounding mass,
Since the film abcd has the power of completely denolarising
the incident light, we are entitled to infer, that its depolarising
axes are coincident with the neutral axes of the rhomboid ; or,
what is the same thing, that the axes of the one are iaclimeth 45°
to the axes of the other; and hence it will follow, that the film
abcd has the same properties as if it had been detached from
the place a b’ba on the upper surface ABCD, and had slid
down into the position abcd. ‘This inference is fortunately
capable of the most rigid demonstration. Let MBEN, Fig. 8.
be the principal section of the rhomboid ; or a section of Fig. 7.
on the line FBf, and let fgqp bea ‘neteaaheg| section of ihe

interr upting fag

168 ON A NEW OPTICAL AND MINERALOGICAL PROPERTY

interrupting stratum or film abed, Fig. 7. The upper and
lower edges, fp, gq, of the stratum, are so distinctly crystal-
lised, that, by the aid of my reflecting goniometer, their ineli-
nation to MB, NF, or the angle Mfp, was found to be 141° 44%
Now, if we suppose that the film fgqp had originally the
position of f g' q p' on the upper surface MB of the rhomboid,
and was brought into its present position by turning round f,
it is obvious, that the angle p' fp must be equal to the acute
angle Bég or BMN of the principal section. But this angle, or its
equal Mfp’, is known to be 70° 51 46", as computed from the
accurate measures taken by Matus: hence the angle p'f p is
also 70° 51’ 46’; and the whole angle Mfp is equal to double
of either of these angles, or 141° 43 32’,—a result which co-
incides almost exactly with the angle which we obtained from
direct experiment.

Here, then, we have a new fact in Mineralogy, of which I
believe there is no other example, viz. That the crystallisation
of a vein is regulated by that of the mass which contains it, the
axes of the vein being constantly inclined 45° to those of the
rhomboid. Nor is this a fact of rare occurrence. The speci-
mens of calcareous spar which are intersected with these veins,
are as numerous as those which are free from them; and
those which occur in the trap rocks on the east coast of Scot-
land, near Montrose, invariably possess this property to such
a degree, that they are rendered semi-transparent by the nu-
merous veins with which they are traversed. When a candle or
a luminous object is viewed through this kind of spar, it is
multiplied in such a manner, that the images are heaped toge-
ther in the most regular forms, and are tinged with the finest
colours, constantly varying with the inclination of the speci-
men.

When these specimens are carefully examined, they exhibit
what has never before been observed, two or more sets of

veins

OF CALCAREOUS-SPAR. 169

_-yeins or interrupting strata, one of which, like abc d, Fig. 7. is
parallel to BF, while the other sets are parallel to BC or BA,
the common sections of the three surfaces which contain the so-
lid angle. When the light is incident almost perpendicularly
upon one of these specimens, so as to pass through two of the
veins, nine images are formed ; and there is a particular posi-
tion of the incident ray, when all these images vanish, except
the colourless image in the centre. This effect can be imi-
tated by the transverse combination of two specimens that have
only one vein or interrupting stratum.

There is another phenomenon exhibited by this interposed
film, which throws new light on the cohesion of solid bodies.
The two surfaces of the film, though in physical contact with
the surrounding mass, so as to adhere to it with the greatest
force, are nevertheless not in optical contact with it. There is
a distinct reflection of light at the touching surfaces, and the
distance of these surfaces is demonstrably ¢ greater than 54 0¢ss0
oY zo,400 Of an inch *

Now, since the irohveet of the interposed film are in every
case kept at such a distance from those of the adjacent mass,
and cannot be brought nearer to it by the force of screws, we
are entitled to conclude, that the particles of calcareous-spar
are not capable of coming into perfect contact, unless when
they are arranged symmetrically ; that is, when the axes of all
the elementary rhomboids are parallel. When these axes are
inclined to each other, the attractive forces by which the par-
ticles are held together, are so much weakened, that they are
incapable of forming a mass perfectly continuous, and devoid
of all internal reflections. This fact is the only unequivocal
indication with which we are acquainted, of the existence of
a polarity in the “ila of crystallised bodies.

* See Phil. Trans. 1816, p- 72, 73. where some analogous experiments are de-
scribed.

Vor. VIII. P. I. Y X,

.

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P ee 7 ¥

X. On the Ancient Geography of Central and Eastern Asia,
with Illustrations derived from Recent Discoveries in the
North of India. By Woucu Murray, Ese. F. R. 8. Epi.

(Read April 29. 1816.)

“HE descriptions which historians and geographers have
transmitted to us of the ancient world, are not generally
deficient either in copiousness or accuracy. The theatre of
those great events, which still interest mankind, may be com-
monly ascertained with sufficient precision. The distinct
knowledge of the ancients, however, was limited to a certain
sphere; after passing which, clouds always begin to envelope
it. |The almost total change of names, the uncertainty as to
their itinerary measures, wl the defects of their mathematical
geography, leave no perfectly fixed point on which we can rest.
Hence, even where copious and interesting details are given, it
is often difficult to determine to what region, or to what na-
tion, these descriptions refer. The question may appear some-
times to be one of curiosity only; yet the curiosity seems na-
tural and liberal; and it is often connected with interesting
questions relative to the history of the human species. It il-
lustrates the extent to which commercial enterprise and activi-
_ ty had reached in ancient times; and often, by enabling us to
compare the modern with the ancient aspect of the same re-
Y 2 gion,

172 ON THE ANCIENT GEOGRAPHY

gion, it qualifies us to ascertain the progress which mankind
have made, during so long a succession of ages.

There are perhaps no regions with regard to which this-
question possesses equal interest, as those which formed the
eastern extremity of the ancient world. The faint and decay-
ing light of science there shone, not upon inhospitable de-
serts, not upon the abodes of rude and pastoral tribes, but
upon civilized, populous, and commercial regions, which, in
all the arts and improvements of life, were not perhaps much
inferior to the Roman empire during its most flourishing
era. Yet the question, what regions these were, is involved in
as deep obscurity as any which has occupied the inquiries of
the learned. Many interesting points are still totally unfixed,
and afford room for the most discordant opinions. Having
been induced to study this subject with peculiar attention, it
has appeared to me, that some light might still be thrown upon
it, by a careful analysis of the ancient statements, as well as by
attentively comparing them with some discoveries which have
recently been made in that quarter of the world.

‘The two nations whose territory formed, to the ancients, the
eastern extremity of the known world, were the Seres and the
Sine, of whom the former were approached by land, and the
latter by sea. Of these the Seres were the most celebrated and
interesting people, and will form the main object of the pre-
sent inquiry ; but it may be convenient to begin with fixing the
position of the Sinz. The approach to their coast is thus de-
scribed by Provemy. After passing the mouth of the Gan-
ges, and a long extent of coast beyond, navigators rounded a
large peninsula, called the Golden Chersonese. Then passing
a great bay (Magnus Sinus) they came to a coast, which was
that of the Sinz, which extended from north to south, with an
ocean on the west. The early modern opinion was, that the

Sinz

OF CENTRAL AND EASTERN ASIA. 173
Sinse were, either in whole or in part, the inhabitants of Mo-
dern China. But D’ Anvittz, who largely reduced the world
-of the ancients, fixed the Magnus Sinus in the Gulf of Siam,
and allowed only a limited navigation along the coast of Cam-
bodia. M. Gossrtin, with bolder scepticism, fixes the Sine
on the coast of Siam, and never allows the ancients to have
passed the Straits of Malacca.

In comparing these three statements, there cannot, I appre-
hend, be the smallest hesitation in preferring the one last men-
tioned. There positively is, beyond India, no coast, besides
that of Siam, which has an ocean on the west. Protemy men-—
tions no island of a magnitude which could at all correspond
to that of Sumatra. ven the Golden Chersonese, though it
may suggest at first sight the peninsula of Malacca, will, when
‘its details are examined, be found better to correspond to that.
of Ava and Pegu. This solution having been acceded to by
Mr Pivxerton, by Dr Vincent, and by all the eminent geo-
graphers of the present age, its correctness may probably be
considered as a point finally decided.

We proceed, then, to the question respecting the Seres, a
people who, by their mysterious remoteness, their wealth and
‘civilization, and the peculiarities of their national character,
‘excited an extraordinary interest in the ancient world. The
information of the Greeks and Romans respecting their terri-

_ tory, as well as a long series of intervening regions, was chiefly

derived from a great mercantile caravan, which, setting out
from the Bosphorus, traversed Asia from west to east, till it
arrived on.the frontier of Serica. This communication does not

_ appear to have been formed, till about the first century, during
the most extended period of Roman power. Its object was to
- supply that empire with the luxury of silk, the use of which, from
being a rare appendage of greatness, had become common to
almost

174 ON THE ANCIENT GEOGRAPHY

almost every class of socicty. The reports of the caravan mer-
chants were collected and committed to writing by Marinus of
Tyre, whose compositions have perished; but the corrected
substance of them is found in the great geographical work of
Protemy. The statements of Protemy, therefore, combined
with some supplementary information from Pry and Ami-,
ANus, must form the authority on which this question is to be
decided.

The earliest modern opinion which I find stated upon this
subject, is, that Serica was Cambalu, or the kingdom of the
Great Khan, that is, the original dominion of Zingis. China,
then, was the Sinarum Regio. Before the time of D’AnviLxe,
however, the prevalent sentiment came to be, that the northern
part of China was the seat of the Seres, the southern that of
the Sinz. Vossivs goes farther, and declares that he who
doubts if the ancient Seres be the modern Chinese, may doubt
as reasonably if the sun that shone then be the sun that shines
now. As that learned and acute writer, however, has not ex-
plained the ground on which so peremptory an opinion was
formed, it has not met with the attention which perhaps it me-
rited. D’Anvinie was the first who applied to this question
that careful and systematic analysis which forms the only true
mode of solution... Having brought the Sina to Cambodia, he
carried westward also the position of the Seres. He assigned
to them an extensive region of eastern Tartary, reaching from
the territory of the Kygurs, or Igours, to the north-western
frontier of China, of which it included only the projecting
corner of the province of Chensi. Mr Prxxerron goes still
farther, and places Serica in Little Bucharia. But M. Gossz-
tin, with his usual boldness, has struck out an entirely new
path. He finds Serica in the north of India, in the district
of Serinagur, including a portion of Thibet.

The

OF CENTRAL AND EASTERN ASTA. 175

The writers now mentioned, however widely discordant as
to other particulars, seem to agree in one point, that of treat-
ing with contempt, and almost with ridicule, the ancient idea
which extends Serica to China. Dr Vincent alone, who thinks
always for himself, has declared his adherence to the latter opi-
nion. His subject, however, has led him to rest almost entire-
ly on the maritime testimonies, which do not, 1 confess, appear
to me so decisive as to the learned writer. They are contain-
ed in the narratives of Arrtan and Cosmas InprcopLeustEs,
persons who never passed Indostan, and collected only vague
and inaccurate reports of the regions beyond. The testimony
of such writers, it would appear, can never be put in competi+
tion with that collected from a company of merchants, who, if
they did not enter Serica, at least habitually trafficked on its
frontier. I certainly concur, therefore, with D’AnvitLE and
the other geographers, in considering Proremy as the main
authority by whom the question must be decided. But,
in adopting their premises, I have been led pretty confi-
dently to a conclusion the opposite of theirs. The works
of Proremy and his cotemporaries appear to’ me to con-
tain a series of statements which fix down, in a very de-
cided manner, Serica as China. As results quite opposite
have been drawn from every analysis yet made of these state-
ments, and as they appear to me to involve a view of the entire
geography of central Asia, widely different from any at present
received, these circumstances, I hope, may plead my excuse:
for: the unexpected length to which the discussion has ex-
tended.. , vs

YL NOSQVERIUET UR OF eee Str ot i

' Considering the decidedly opposite opinion which has been
held by the most eminent geographers of the present age, I
should perhaps have hesitated in laying before the Society the

result of my inquiries, had they not been so strongly supported.
; -

176 ON THE ANCIENT GEOGRAPHY

by recent discoveries in the north and north-west of India.
These appear to have not only furnished new materials for the
solution ef the question, but to have laid open radical errors,
which have hitherto darkened the view of modern inquirers.
When these are removed, I am persuaded that the reports of
the ancient writers will be found clear, consistent, and satisfac-
tory, to a degree beyond what has yet been suspected.

The principle hitherto proceeded upon, by all modern geo-
graphers, is, that provided their system appears to be support-
ed by a few names and particulars found in Proremy, they are
at perfect liberty to impute to him any errors, however enor-
mous, which may be necessary to fill up their hypothesis. M.
Gossein broadly lays down the maxim, that all precise know-
ledge, on the part of the ancients, terminated with the range of
the Beloor ; and D’ Axvitie repeatedly warns his readers against
expecting more than a very vague and general coincidence
between the actual features of the country and Proiemy’s de-
scription of them. This last, he observes, must be corrected
by the more copious and accurate information of modern
times. My own researches, on the contrary, have led to a
pretty decided conviction, that the ancients knew more respec-
ting these regions, than has been, or is still known to the mo-
derns ; that they knew more consequently than those very emi-
nent geographers who have treated their authority so lightly.
I believe, if the statements of Prozemy be taken simply as they
stand, and be carefully collected and: arranged, they will be
found to exhibit correctly all the grand outlines of Central and
Eastern Asia.

Considering the subject in this view, it may be advantageous,
before entering upon the proposed analysis, to notice some
preliminary facts, which may throw light on the general degree
of knowledge possessed by the ancient writers respecting this

part

OF CENTRAL AND EASTERN ASIA. 177

part of the world. These are furnished by the very laudable
efforts already alluded to, made by our countrymen in the East,
to improve the geography of India, and the neighbouring re-
gions, particularly by the recent mission to Caubul. A num-
ber of leading points have thus been satisfactorily settled ; and
the means are afforded of forming a comparative estimate be-
tween Proremy’s information and that hitherto possessed by
modern geographers.

One of the leading questions in Indian geography, has al-
ways been that relating to the course of the five great rivers
that water the, Punjab. It was ascertained by the gentlemen
attached to the Caubul mission, that these, after forming two
great branches, at length united into one, and poured their
waters into the. Indus by that common channel. They had
uniformly been represented before as falling by two separate
and somewhat distant channels. This is justly noticed by a
learned writer in the Edinburgh Review, as one of the most
important recent geographical. discoveries. It certainly was
such to the moderns: but it merely restored the delineation
which had been given, nearly two thousand years before, by
Protemy. His map exhibits the five rivers, which, after torm-
ing two great branches, unite and fall into the Indus, precisely.
in the manner described by Mr Exrurnsrone. Purmy’s testi-
mony is to the same effect; he describes the Hydaspes falling
into the Indus, guatuor alios amnes afferentem.

In endeavouring to prove the imperfection of Protemy’s
knowledge relative to the north of India, M. Gossexin point-
edly refers to his placing the source of the Ganges in the
Imaus (Himalaya) instead of deriving it from Thibet. Here
also, however, Protemy happens to be in the right. In 1808,
the Supreme Government of Bengal, at the instance of the late.
Colonel Cotzsrooxe, sent a mission to explore the origin of

Vou. VIII. P. 1. Z this

178 ON THE ANCIENT GEOGRAPHY

this celebrated stream. The party followed its course till it
became little more than a rivulet. Their further progress was
arrested by precipices, and by the snows, under which its in-
fant course was buried. But they made such observations,
and collected such intelligence, as left no room whatever to
doubt that it descends from the Himalaya, and that the long
course which our maps assign to it along the table land of Thi-
bet, has no existence in fact. They found also, that, contrary
to general opinion, the sources of the Jumna, and of the Sa-
rayu, the head of the Gogra, were in the same chain, and at a
small distance from that of the Ganges ; as they had been pla-
ced by Protemy, who has not, indeed, been so happy as the
moderns, or, indeed, as Priny has been, in delineating some
parts of their subsequent course.

The gentlemen employed in the Caubul mission, extending
their researches to the north-west of India, have brought to
light some other important features. One of the most promi-
nent is the river Kaumah or Kama, which rising on the oppo-
site side of the same range which gives origin to the Oxus,
pursues a northerly course of nearly four hundred miles, till it
falls into the Indus, of which it forms the largest western tri-
butary. Near its junction it receives the river of Suaut, so
called from a beautiful and fertile valley through which it
winds. Of these streams, previous to the mission, no trace ap-

peared in our modern maps; but in turning to Proremy, we-

shall find them both delineated, under the appellations of the
Coe and the Suastes, with some variation as to magnitude, but
correctly as to relative position and mode of junction ; while
the river of Caubul is noted as a branch from Parapomisus. It

thus appears, that Protemy’s knowledge of the northern boun-

dary of India, though not perfect, was, on the whole, decidedly
superior to that of the best informed modern geographers ; and
we

a a 2

OF CENTRAL AND EASTERN ASIA. 179

we find him delineating with success, grand geographical fea-
tures, hid as it were in the most secret recesses of Asia, which
had remained to them entirely unknown. Surely, then, it can-
not be denied, that some regard is due to his authority, and
that his delineations may possibly prove correct, even where
they do not exactly coincide with those of our modern maps.
. It is now time to proceed to the main object, of exhibiting
Protemy’s delineation of Eastern and Central Asia, and com-
paring it with the actual features of that Continent. In this
analysis, it will be convenient to follow the movements of the
great caravan, from which he derived his information. Setting
out from Byzantium, it proceeded through Assyria, Parthia, and
other regions of Asia, to Bactria, a country still known under
the appellation of Balk or Bulkh. It seems early to have been
the depot for the caravan-trade of Central Asia, and had thus
acquired a degree of wealth and splendour unknown to the
barbarous regions that surrounded it. Thence the travellers
proceeded into Sogdiana, which appears in Mr Exruinstonn’s
map under the modern appellation of Shoghnaun. The route,
which had hitherto been easy and level, assumed now an en-
tirely different aspect. Before ascending, however, into that
vast mountain world, which Asia incloses in her bosom, it may
be necessary to pause, and to take a brief view of its general
Shraehiares! 4! fi treriia wah) oe Petuort
It is well known that Indostan is’ Icaridesiba on oe south by
a table land of extraordinary elevation, called Great and Little
Thibet. Two parallel chains, running from east to west, prop
this mighty bulwark of Asia. The southern barrier is formed
by that) immense chain known under the names of Hindoo
Coosh, and Hemalleh or Himalaya, which forms the northern
limit of India. The whole extent of it is covered, to a great
cm with perpetual snow, and every measurement yet made,
Z2 from

180 ON THE ANCIENT GEOGRAPHY

from Peshawer to Nepaul, has made it exceed 20,000 feet
above the level of the plain, being higher than the highest
peaks of the Andes. The whole is recognised by Protemy un-
der the name of Imaus. The northern range, known by the
uncouth appellations of Mooz Taugh or Karrakorrum, is, I ap-
prehend, described by him under that of Mons Ascataneas.
Though its absolute elevation appears to exceed the Himalaya,
yet, from the high level of its base, it does not present so for-
midable an aspect. At the western extremity of these two
chains, we find another, running at right angles to both, con-
necting them, and shutting in the western side of the table
land. This is called the Beloor Taugh, (or Beloor, as taugh
is merely the generic name of mountain.) It forms the east-
ern limit of Shoghnaun, the ancient Sogdiana, and thus coin-
cides with the Montes Comedorum, the first ascent which the
caravan is represented as having had to encounter. M. Gossz-
LN, the most sceptical of modern inquirers, recognises the co-

incidence, so that, up to this point, there is no controversy. .
Mr Exrurnstone’s map exhibits a route up the valley of
the Oxus, and then ascending the Beloor, which has every ap-
pearance of being the route followed by the merchants upon
this occasion. Having surmounted this laborious ascent, they
descended into a plain, not arable or fertile, but affording abun-
dant pasturage to the nomadic tribes by whom it was traver-
sed. Then ascending a valley, by a route which I suspect to
be that traced by Mr Exrursronr, up the valley of the La-
dank, they came, first, to the Stone Tower, a singular appella-
tion which is never explained, and then to another station,
where a grand rendezvous took place of all the caravans that
were proceeding to the great emporium of the East. This
union was formed, with the view of overcoming an obstacle
more formidable than any they had yet encountered,—the migh-
ty

ee

*

GE ar eS ee

OF CENTRAL AND EASTERN ASIA. 181

© ty range of Imaus, which, after running for a great space from

east to west, turned suddenly to the north, and stretching far

~ into Scythia, separated that vast region into two portions, Sey-

thia within, and Scythia without, Imaus. This chain forms
thus the key to Proremy’s geography of Central Asia; and as
my views respecting it differ very much from those hitherto
entertained, it wine he necessary to enter into a short discus-
sion.

~ All modern geographers, so far as I know, have conceived
that the Imaus must, in some shape or other, be identified

- with the Beloor. D’Anvritr, Rennetr, Gosserin, Pincervron,

however they may differ in other respects, seem to consider
this as a point placed beyond all dispute. Even Major Rrn-
nELL, while he clearly points out, that Prorrmy’s statements
place the Imaus in a very different quarter, does not allow
himself to suppose that those statements could be correct.
Now I think it will appear on a very slight consideration, that
every system which identifies the Imaus with the Beloor, is an
entire subversion of all the descriptions and statements of
Prorzmy. Between these two ranges he places a great nation,
or rather class of nations, under the appellation of the Sacz.
Yo their territory he assigns fifteen degrees of longitude ;
_ which, upon that parallel, and making every allowance for the
defects of his graduation, cannot be less than from five to six
hundred 1 miles in direct length from east to west. This im-
* mense region, which equals half the breadth of Indostan, is re-
duced by ‘the! present system to what M. Gossexin calls one of
the Gorges of the Beloor, a mere valley or glen between two
of its branches. Thus, too, the Sacz are entirely severed from
India, of which however both Protemy and Si eid describe

them as forming the northern ee
ji toad wet Md«. Boreaertgio yt Fe pha deg u The

182 ON THE ANCIENT GEOGRAPHY

The delineation of the country of the Sacz, will be found to
correspond, in every respect, with that given by Mr Expuin-
stons of the Plain of Pamere and Little Thibet. It was
bounded on the south by Indostan, from which it was separa-
ted by the ridge of Imaus. On the north it was bounded by
the next parallel chain, Mons Ascataneas, which cannot possi-
bly be any other than the Mooz Taugh, to whose name, in-
deed, it bears a rude resemblance. It extended eastward from
the Montes Comedorum (the Beloor) to somewhat beyond the
head of the Ganges ; precisely the dimensions of Little Thibet.
Again, it appears from Proremy, that the merchants, after as-

cending the Beloor, proceeded for several hundred miles to the |

south-east, which is precisely the direction of the table land.
The mere aspect of Protemy’s map, and that of Mr Expnry-
sToNr, present a striking similarity of form and geographical
features. It seems plain, then, that geographers, in placing
the Sace among the defiles of the Beloor, or extending them
towards Cashgar, have disregarded the whole tenor of Proxz-
wy’s statements. It is true, Eprist has given us a region called
Sakita, which seems merely to occupy the summit of the Be-
loor. But we must observe, that Sace, in Pxuvy and Prore-
- my, was a generic name for a number of nomadic and pasto-
ral tribes. It is well known that such names, among the civi-
lized nations of antiquity, were usually formed by extending
that of the nearest tribe to a long range of territory behind.
It was natural, therefore, that the Sacz, the first people who.
occurred, on ascending the mountains, should give name to a.
succession of similar districts, till another grand barrier of na-

ture interposed. We are not, however, left here to mere infe-

rence or conjecture. Prrny, after mentioning the Scythian
tribes east of Bactria, expressly says: “ Perse omnes illos Sa-

“ cas appellavere, a prowima gente.” The district of Sakita,

therefore,

°

OF CENTRAL AND EASTERN ASIA. 183

therefore, admitting it to be the country of the Sacz proper,
in no degree expresses the extent of that which, by Priyy and
Protemy, was called the Sacarum Regio.

There is one, and I think one only, important discrepancy.
Neither the Ladauk, the Indus, nor, indeed, any river whatever,
is to be found in Protemy., This defect, though serious, can-
not, I think, be placed against the perfect agreement of every
other feature. My impression is, that Protemy emitted these
rivers from not knowing whither to lead them, for he, in com-
mon with the rest of the ancients, never suspected that the In-
dus or any river, penetrated across the snowy chain; and the
last lesson which geographers ever learned, was that of con-
fessing their own ignorance. The omission seems supplied by
Pury, who was not fettered by any such complete or mathe-
matical delineation, and. who expressly states, that several ri-
vers, and, among others, two of great magnitude, traversed the
country of the Sacz.

But what is this mighty range of Inari or what other chain
is there, besides the Beloor, which traverses Asia in such a di-
rection? Whatever we may think as to where it really exists,
there can be no doubt, as Major Rennetx indeed admits,
where Protemy meant to place it ; for besides all the other in-
dications, he states it as running northwards trom Palibothra,
and somewhat to the east of the sources of the Ganges. It
ought then to be a chain dividing Great from Little Thibet,

parallel to the Beloor, though at a great distance, and shutting

in the eastern side of the table land. Such a chain seems
scarcely recognised by modern geography ; and yet there can-
not, I apprehend,-be the smallest doubt as to its existence, be-
cause it is now ascertained by the combined reports of Major
Turner, and of the Caubul mission, that in this quarter must
lie the yet unexplored sources of the two greatest rivers of In-

dia,

184 ON THE ANCIENT GEOGRAPHY

dia, which here separate, and flow in opposite directions ; on
one side, the Indus, with its tributary the Ladauk ; on the
other, the Sanpoo, or Barrumpooter, both of which, at the
highest point to which they have been traced, are already large
streams, that have evidently flowed from a great distance. It
is well known to those who are accustomed to such researches,
that the point at which great rivers thus rise and separate, is
always the most elevated of any region. The proof from ana-
logy is therefore so strong, as to render perhaps any other ar-
gument superfluous. But if we collect the slender notices that
exist, this feature will not be found wholly destitute, even of
modern testimony. The little we know relative to.Great Thi-
bet, is chiefly derived from Dunatpr’s report of the mission of
two Lamas from the court of China. ‘Their object was, to.
make a map of that region, and to ascertain the sources of the
Ganges. On their return they stated, that there was a great
chain of mountains separating Great from Little Thibet; that
from one side of this chain descended the Barrumpooter, and
from the other, which they did not visit, the Ganges, with the
Ladauk falling into it. It is now certain, that they were mis-
taken as to the Ganges; but I think it probable, that what
they supposed to be that river, was really the Indus; be-
cause Mr Expminsrone’s map exhibits the Indus holding the
same course along the table land of Thibet, and receiving the:
Ladauk in the very same manner that they understoéd. the
Ganges to do. We have therefore the testimony of these per-
sons, that there exists a great chain of mountains in the very
quarter, and running in the very direction, indicated by Protemy.
In 1725, the missionaries Desiperr and Freyre made the
journey from Cashmire to Ladauk *.. They describe it to be
a

* Lettres Edifiantes, vol. xi.

EEE

‘6 RE Rete r=

OF CENTRAL AND EASTERN ASTA. 185

a succession of hardships, perils, and hair-breadth escapes, such
as never mortals before encountered. Whether the worthy
missionaries might somewhat exaggerate perils through which

_they themselves passed, I shall not inquire; but we have also
.the ‘report of an Indian traveller to Mr Exprrnstone, that a
little beyond the Cashmirian frontier, there began an uninter-

rupted, and, in some places, a very steep ascent, of thirteen
days, to’ Ladauk. That place itself is described by the mis-

‘sionaries, as the: abode of almost perpetual winter, and all the

hills around covered with snow. Yet the river being already
of considerable magnitude, this can only be a lower stage of
the great eminence from which it descends. Ladauk, too, be-
ing the established line of communication between Great and
Little Thibet, must be the most level one, and the mountains
must present, at every other point, a still loftier barrier.
_ There appears, thus, no reason to doubt, that the Ridge of
Imaus exists, and in the very region where it is placed by Pro-
tEMy. Up to this point, therefore, his description of Cen-
tral Asia, taken in its simple and obvious sense, proves to
be consistent with itself; and with the ascertained features 5
the region which it professes to delineate.

Having passed this formidable barrier, we arrive at the ex-
tensive region’ of Scythia extra Imaum. Upon the data now

‘stated, this ‘can only be Great Thibet, with an extent of Tarta-

ry stretching’ indefinitely northwards. After’ Scythia comes
the famous Serica, the ultimate object of inquiry, the remotest
country known’ to the’ ancients. If Scythia extra Imaum be
Great Thibet, the next great country must be China. But as.
this is a point so curious | and so much contested, it may be ne-
cessary to examine, whether the inference derived from the ge-

neral line of Proremy’s course through Asia is ie an by
h biiiaes VILL. Pil Aa his:

186 ON THE ANCIENT GEOGRAPHY

his view of the situation and geographic relations of Serica it-
self.

The first proof to which we shall attend is that derived from
his longitudes. These are universally allowed to carry Serica
very far beyond Thibet or Eastern Tartary. 'M. Gossexi,
however, insists, that as they carry it-beyond China also, and
into the very heart of the Pacific, no regard whatever can be
paid to them. That eminent writer, however, has here re-
markably overlooked his own important illustrations of the
mathematical geography of Protemy. He has shewn, that the
errors of that ancient writer, whether they reside in the value
of the itinerary stadium, or, as I rather suspect, in the measure-
ment of the great circle of the earth, are not random errors ;
that they proceed in a regular train, and that there exist data
by which they may be calculated. It appears, that by redu-
cing his longitudes in the relation of seven to five, they will
all approximate pretty nearly to the truth. Now the remotest
longitude given in Serica is 180 degrees east from the suppo-
sed meridian of the Fortunate Islands, which was fixed 23 de-
grees to the west of Cape St Vincent. 180°, reduced in. the
above ratio, will give 128° 30’, or 117° from the meridian of
London, which is three or four within the eastern frontier of
‘China. It thus falls short. of the ocean, which, will account for
the only circumstance ascribed to Serica which does not agree
with China, that of its being bounded on the east. by unknown
lands. The truth is, a bounding éerra incognita was, quite a
theory of the school of Marinus, which they everywhere made
to sueceed to, the original theory of a circumambient ocean.
If the narrow peninsula of Malacca was considered as stretch-
ing into an unknown extent of continent, much more might
this be supposed of an empire so yast as China, and of which
the interior was so little explored. But Mera, Puiwy, and

in

——_-

a tet

OF CENTRAL AND EASTERN ASIA. 187

in general, all writers not of this school, who treat of Serica,
attest the general belief of antiquity, that it was bounded by
an ocean on the east. Pury even calls it the Seric Ocean.

The extent of Serica, estimated according to the graduation:
of Protemy, willbe found to be about fourteen hundred miles
from, north to south, and eleven hundred from east to. west ;
which comes wonderfully near to the actual dimensions of mo-
dern China. :

. Protemy represents Serica as traversed by two great rivers.
It is impossible, with our slender information, to bring home
the details of these rivers. But the fact is, that there are just
two great rivers in China. These, too, for a considerable time
after entering, the empire, flow north-west, like the rivers of
Serica’; and it deserves notice, that there are no great rivers in
this,part of Asia, except these two, which flow in such a direc-
tiga Motsanayl sabortd ‘iter , 6
Let us now examine the geographical relations of Serica to
the neighbouring countries. This is of course to be done on
the principle which seems fully established by M. Gosszxin,
that the country of the Sinz is. Siam ; in consequence of which,
India beyond the Ganges is limited chiefly to the Birman em-
pire. Proremy states, that all the natives of India whom he
met with in the ports of Egypt, assured him that the Seres.
were beyond the Sinz. This description will apply to no.
country of Asia except China. He states, that India beyond.

the Ganges is. bounded on the north, partly by Scythia, and

partly by Serica... Ava, accordingly, is bounded, on that side,
partly, by Thibet, and partly by the Chinese province of Yu-
nan. Again, the Sinz are bounded on the north by Serica.
alone. Siam, accordingly, is. so bounded by China; for the.
small intervening kingdom of Laos would of course be included.
-in,one or the other. Again, Scythia extra Imaum, is bounded.

Aa 2 on:

188 ON THE ANCIENT GEOGRAPHY

on the south by India beyond the Ganges alone, not at any
point by India within the Ganges. Scythia extra Imaum, then,
is entirely east of Indostan, while Serica is east of Scythia ex-
tra Imaum. It is needless to say to what country such a de-
scription would apply, and how inconsistent it is with the
idea which makes Serica border upon, or make part of Indo-
stan,

To these very precise statements of Protemy, it may be pro-
per to add those, though much looser and more vague, of Pxr1-
ny and Ammianus. Purny states, that the last country dis-
tinctly known, (ubi gentes plane constent, ) was the chain of moun-
tains called the Emodus. The moderns seem always to ima-
gine, that Imaus and Emodus are merely different names for
the same chain. But though instances may be found of their
being so used, these never occur in the writings of the more
accurate geographers. With them Emodus is east of Imaus,
or rather, perhaps, it is the same chain after passing the head
of the Ganges. This distinction is made by Proremy in the
most precise manner. With him Imaus separates India from
the Sacze, Emodus from Scythia extra Imaum. Prrvy also re-
peatedly enumerates Imaus, Emodus, Caucasus, Parapomisus,
as at least separate parts of the great chain which traverses
Asia. After enumerating the nations between the Indus and
the Ganges, he enumerates those between the Ganges and the
Emodus. His Emodus, then, like that of Protemy, is evident-
ly a chain east of the Ganges. The great region, then, which
lies east of the Emodus, cannot well be any other than China.
It appears to me that Piiyy confounded under the name of Se-
res all the nations who dwelt beyond India, as the author of
the Periplus confounds them all under the name of Sina. I
know not whether Lanos can be pronounced to be Laos ; but
the Chryse Promontorum can scarcely be any thing else than

the

—————————S—— es

ae

Wee

OF CENTRAL AND EASTERN ASIA. 189

the Golden Chersonese. This will account for the assertion,
that the people of Taprobane were placed at a small distarice
-from, and carried on traffic with Serica.

‘We have thus found, that the leading astronomical and geo-
graphical features ascribed to Serica, agree exactly with China,
and can apply to no other country. The moral features are, if
possible, still more decisive. These do not enter into the plan
of Protemy, but they are noticed by P uiny, and detailed at
some length by Ammianus. The Seres are represented as a
people frugal, quiet, sedate, and tranquil beyond all others ;
as, of all nations the most unwarlike, and the most averse to
the use of arms; as shunning, with the most studious care,
the society and intercourse of other nations, and scarcely
ever” allowing them to enter their territory ; as carr ying on
trade at a fixed frontier station only, and under the strict-

est precautions 3 as selling their own commodities, without
receiving” ves aden eabaitied of other nations in return *.

oe PoOTH This
ert yi | eb uae
_ * Tt may be proper here to notice a report which militates against our view
of the subject. Some authors describe the Seres as a people remarkable for their
_ honesty. “Thus Meta says, ‘“‘ gens plenum justitiz, ex commercio, quod re-
« bus in solitudine relictis absens peragit, notissimum.” I think it evident,
that this character is solely founded upon the rumour so often repeated,
that they and their neighbours carried on trade without meeting, but by
merely laying down the goods in each, others absence. It. is remark-
cable, that rumours o of a trade so conducted have been transmitted in all ages,
from the remote extremities of the known world, without having been con-
‘firmed in any instance by the testimony of a credible eye-witness. This in-
clines me to believe that it is a mere poetical fable, taking refuge, like other
fables, at the dim boundaries of knowledge. While such descriptions were
afloat, t the quiet and. cautious - habits of the Seres would very naturally cause
the applicati on to be made to them. If such a trade did exist, it must have
been a | political ‘precaution ; A ‘and, ‘in that case, “public authority would Paine
that fair-dealing, without which it could not subsist. We may finally remark,
: that

190 ON THE ANCIENT GEOGRAPHY

This is exactly the picture of the modern Chinese; and it is
one totally inapplicable to any other nation of any age. If
there are any from whose description it is most peculiarly re-
mote, these certainly are the rude tribes who inhabit 'Tartary,
Thibet, and the mountainous districts to the north of India.
It is a very remarkable phenomenon in the history of man,
and one which Southern Asia alone can present, that a de-
scription written nearly two thousand years ago, should paint
this celebrated people with as much. precision, as if it had
been composed by a writer of the present day.

If, then, Serica be considered as China, and the divisions of
Central Asia be regulated accordingly, then these divisions, in
all their grand outlines of extent, geographical features, rela-
tive position as to themselves, and to the kingdoms of Southern
Asia, will correspond exactly to the delineation of Protemy.
Even in the moral and political features of the remotest of
these countries, there is found the most surprising correspond-
ence. Nothing, therefore, remains to complete the proof, but
to consider some details, which appear, at first sight, to mili-
tate against this supposition.

DA NvILLE remarks, that the general aspect of Serica, as ex-
hibited by Prozemy, is that of a country similar to Scythia.
The truth of this observation cannot be denied. There is no-
thing in his description of the interior of Serica, which suggests
the idea of modern China. On the contrary, there is the broad

fact,

that this character is ascribed to the Seres only by secondary writers, and that
Puiny and Ammranus, our best and most copious authorities, make no mention
of such a feature. Ammianus, indeed, mentions the mode of trade above alluded’
to; but he omits entirely to draw from it the tid which is made by
Mena.

See

OF CENTRAL AND: EASTERN ASIA. 191

fact, that it is represented as traversed by chains of mountains,
a feature which the latter region dees not present. This is a
very important difficulty, and will require some considera-
tion.

It is not easy ri us to ascertain the degree of correctness
with which Protemy has described Great Thibet, from our be-
ing ourselves almost totally ignorant of that region. We can
only form a favourable presumption, from the accuracy with
which he has delineated. those conterminous regions, with
which we are better acquainted *.. But it is certain, that on ap-
proaching the confines of Serica, that twilight of knowledge
must have-begun, which always precedes its total extinction.
A peculiar source of obscurity there arose. It was the deci-
ded policy of that country, as it has always been of modern
China, to shut the empire, with the most jealous care, against
the entrance of foreigners. Commerce was permitted only at
one single point, and it was carried on with the least possible
communication ; nay, according to an often repeated assertion,
without the parties even seeing hs other. It was impossible,
therefore, that the ancient writers could possess authentic de-
tails relative to the interior of Serica. But an infirmity beset
Protemy, which continued always to prevail among geogra-
phers, till the great reform effected by D’ ‘Guia It was
conceived. discreditable, that any district within the limits of

la the

. I shall mention, however, the following names, in which the resemblance is
somewhat rude; but allowance must be made for the passage through Grecian
organs; and the positions correspond very precisely. Chauranei (juxta Emodos
Montes), Mount Chumularee. Achassa,—Lassa. Chate ( Khatai, Gr.) Khata,

on the Upper’ Barraimpooter. | (See M. Vansirrart’s Account of Assam. Asi-
at. Research.) vol., vii.. Damna,—Daum., Ottorocoras,—Uttarcul or Ootrecoie.
This last must be understood i in connection wath the observations which follow

in the a

?

192 ON THE ANCIENT GEOGRAPHY

the known world, should appeat on the map as an entire blank.

As they were far, however, from being all perfectly known, it
became often necessary, in acting upon this principle, to have
recourse to somewhat arbitrary measures. One of the most
common was, by extension or repetition, to fill up the un-
known parts out of the known, a process of which many in-
stances must have occurred, to those who are versant in such
researches. The combined celebrity and obscurity of the pre-
sent object, might seem to authorise more: than the usual li-
cence. Accordingly, it appears to. me, that Proremy has en-
tirely protracted, into Serica, the geographical lines of Eastern:
Scythia. Of this operation there appear, in. the very descrip-
tion, to be pretty evident traces. We have Issedon Scythica,
Issedon Serica; while, of the Casian, Auzacian, and Emodian
mountains and regions, the western part is in Scythia, and the
eastern in Serica. It is, I think, quite unexampled, that any:
great country, much less: so immense a country as Serica, and:
one separated by such powerful barriers from the rest of the:
world, should consist almost entirely of districts protracted out
of another region, with which: it has no natural or political con-
nexion. We may observe, that Protemy stands alone in re-
presenting Serica to be a country of mountains. AmmMiaNus,.
as a historian, has given, at some length, a: description of its.
general aspect. His representation decidedly is, that of a plain.
of vast extent and luxuriant fertility, and which was only sur-.
rounded by a circuit of mountains. I think. it even appears,.
that the same idea was'in Protemy’s mind; for he begins by.
saying, “ Mountains surround the Seres ;” though in the deli-.
neation he certainly never reaches beyond these mountains,

From the whole of what has now been said, it may be infer--

red, that all the details given respecting Serica are to be sought,

and may perhaps be hereafter found, with some degree of pre-_

cision,,

—————————<<@“<< Se

— «2 =e eet eee,

‘OF ‘CENTRAL AND EASTERN ASIA. 193

eision, in the eastern extremity of Great Thibet. But the geo-
graphical outline, the broad line of distinction always drawn
between Serica and Scythia, the general aspect of the former,
and every thing that is said respecting its inhabitants, leave no
room to doubt, that the Serica of the ancients, the country of
silk, the abode of this peculiar and singular people, could be no
other than the modern China. Even the short notices which
are given respecting it, seem sufficient clearly to evince, that
in arts ‘and civilization, and in its whole moral and political as-
pect, this celebrated region was then as nearly as possible the
same that it exists at the present day.

I have thus exhibited at some length that interpretation of
the system of Protemy and his cotemporaries, which appears
to me alone consistent with their statements, and with the real
aspect of those vast regions to which they refer. As, however,
opinions so opposite are entertained by the most eminent geo-
graphers of the past and present age, it may be necessary, be-
fore concluding, to inquire, whether their statements exhibit
the same correspondence with the ancient descriptions. D’ An-
vite here claims the precedence. He, as formerly noticed,
places Serica in Eastern Tartary, north of the Creat Desert,
and extends it from the country of the Eygurs to the north-
west extremity of China. In this system, Major Rennexu has

- declared his almost unqualified acquiescence ; so that it is sup-

ported by very high authority indeed. Yet I think it will ap-
pear, on a careful inspection, that it breaks up completely
all the relations established by Protemy between Central and
Southern Asia. It separates the Sacze from Indostan, the Ex-
tra-Scythians from India beyond the Ganges, and the Seres
from Siam, by an immeasurable distance. Besides, it is ad-
mitted on all hands, that the ascent of the Montes Comedo-
vum (the Beloor) must be considerably south of Cashgar, to
reach which, the caravans must have proceeded almost directly

Vor, Vill. P. L Bb north.

194 ON THE ‘ANCIENT GEOGRAPHY

north. On the contrary, Pronemy mentions very expressly,
that, after ascending the Beloor, they turned to the south-east,
and continued for more than two hundred miles in that direc-
tion. Unless, therefore, they had mistaken north for south, it
was impossible they could ever arrive at Cashgar. It is only
on a superficial view that this system can appear to be favour-
ed by the graduation of Protemy. From the influence of the
same causes which we have noticed as acting upon the longi-
tudes, all his latitudes in Central Asia are greatly too high.
M. Gossetry, however, has proved, that the errors of Prore-
my’s graduation become great only by accumulating along an
extensive line, and that it expresses, with tolerable correctness,
the relation between two places at a moderate distance from
each other. The source of the Ganges, and, with slight varia-
tions, all the points along the northern boundary line of India,
are placed by Pro.emy in latitude 37°, (about 6° too high).
Now, one point in the caravan-route through the Sacarum Re-
gio, is only 39°, and the highest is 43° ; being six of Protemy’s
degrees, less than five of ours, north from the source of the
Ganges. Lapavx is six; so that in fact this statement com-
ines’ with the other indications, in fixing down the cotritry of
the Sace to Little Thibet.

In corroboration of these proofs, it may be added, that silk
is not the product of this region, and that we should look there
in vain for the vast and fruitful plains described by Ammranus.
Much less is it probable that the Seres, a mild, timid, unwar-
like people, should ever have inhabited the country of the
Huns and.the Moguls, whose hordes have in all ages spread
desolation over the eastern world.

The only ground, so far as 1 can discover, upon which this
system has rested, is one name, the influence of which upon

the

OF CENTRAL AND EASTERN ASIA. 195

the geography of Central Asia, has been so remarkable, that it
may require a little consideration. It has, I think, been consi-
dered unquestionable by all modern geographers, that the Ca-
sia Regio of Protemy can be no otlier than the modern Cash:-
gar. Not only has this been the sole prop of D’Anviuxex’s hy-
pothesis, but it has perhaps been the main source of the perti-
nacity, with which the Beloor has been always identified with
the Imaus., I,must here premise, that no proof has been used
ina more irregular and licentious manner, than the one in ques-
tion. The ever rolling tide of war and. revolution, has swept
from almost every region the names borne by it during the age
of which we are treating. If we make an exception of great
natural, objects, mountains and rivers, there is not perhaps one
name in twenty which bears any resemblance; and it is quite
as likely, that this one should be the result of accident as of
real identity... 1 would therefore lay down a principle which
will scarcely perhaps be dissented from by any who have had
the least experience in such researches: Where the. descrip-
tions correspond, a similar name may be considered as fixing
the spot with greater certainty and precision: Where there is
no such correspondence, a mere name can never be set against
those grand features of nature which, remaining the same from

age to age, form our only sure guide in such an investigation.
. The Casia Regio is a territory of Scythia extra Imaum, bor-
dering upon, and even, aecording to Protemy, extending into
Serica.. Cashgar is at an immense distance from China or
Great Thibet ; it is situated close to the Beloor. It would be
a mere repetition of every thing that has been said, to prove
that the identifying of the two breaks up the whole scheme of
Pyoxemy’s geography of Central Asia; and that, according to

him, .Cashgar ought to form part of Scythia intra Imaum.
There is a still more decided and tangible discrepancy. Cash-
Bb 2 gar

196 ON THE ANCIENT GEOGRAPHY

gar is situated very near to the head of the Jaxartes ; the Casia
Regio is immensely distant from any part of that river. Now
I submit to the learned, whether the imperfect resemblance of
a single name can be suflicient to overthrow, not only the
whole general description of Asia, but the particular descrip-
tion of the very country to which it is applied. It happens
very accidentally, however, that we stand here on much strong-
er ground; for it is surprising, that geographers should have
overlooked that Protemy has in another place given precisely
both the name and situation of Cashgar. It is in a people of
Scythia intra Imaum, the Cachage Scythe, whose situation is
not precisely laid down, but it is mentioned, that they lie near
to the Jaxarte, the nation who inhabit the banks of the Jaxar-
tes. I conceive, therefore, that every argument founded upon
this name must fall to the ground ; after which there will net
remain a single prop on which this system can. rest.

Mr Pivxerton’s hypothesis, which. places Serica in Little
Bucharia, seems liable to all the objections already urged
against that of D’AnviLLE, to a somewhat greater extent, and
with the addition, that he disregards entirely the dimensions
assigned by Protemy to those regions. ;

M. Gossery has formed a very different system: He cone
ceives the north of India, with the contiguous portion of Thi-
bet, to be the real Serica of the ancients. To reconcile this
with the statements. of Proremy, he supposes this geographer
to have committed an error, when, in extending the caravan
route beyond the Purgos Lithinos, he gave it an eastern direc-
tion. It ought, he conceives, to have been southern, which,
instead of carrying the travellers towards China, would have
brought them directly to the north of India. Now, Lam fully
aware, that the ancients erred often very materially in what the
French call orienting their lines ; that is, in giving them a pro-

per

OF CENTRAL AND EASTERN ASFA. 19%

_ per direction as to the points of the compass. But I think

there is scarcely an example, that so extensive a line, reaching
across nearly half a continent, should be so entirely changed.

_ Tbelieve also that the error occurs chiefly in vague boundary

lines, or in coasts, where the vessel, according to ancient prac-
tice, followed all the windings of the shore, and was acted upon
by various tides and currents. It might then be difficult to as-
certain the general line of their course, and an erroneous idea,

once formed, might not readily be corrected. But a land-

route is in a much more direct line; and as travellers have an
obvious interest to know the direction in which they are mo-
ving, so the most superficial observation of the celestial pheno-
mena will enable them to avoid any error of great magnitude.
ProLeMy, we may observe, enumerates very particularly all the
changes of direction made by the: great caravan in its course
through Asia. From the passage of the Euphrates to Hecatom-
pylos, the capital of Parthia, he makes it east; which that line ve--
ry nearly is. Thence'to the capital of Hyrcania, north ; that is,.,
north-east, as east is always understood to be the general direction.

Then to the capital of Margiana, by a circuitous route through:

Aria, first south, and then north ; to Bactra, east ; to the ascent
of the Montes Comedorum, north-east ; which agrees with Mr
Epuinstone’s map ; then south-east, being the direction of the:
plain of Little Thibet ; then again north-east, which is the di-

rection of the valley of the Ladauk, the established line of
communication with Great Thibet. Thus, along the whole of

this immense line, the minutest variations are clearly recogni-
sed; and the improbability is greatly increased, that, in the
next stage, so extraordinary an error should be committed:
The merchants farther informed Mazinus, that, lengthened
as the march now described had been, it formed scarcely half

_ ofthe peregrination to Sera; that from the Purgos Lithinos, com-

menced.

198 ON THE ANCIENT GEOGRAPITY

menced a laborious journey to that capital, which could not be
performed in less than seven months. Admitting, with Prorx-
my, that a large allowance is to be made for the delays and dif-
ficulties of the journey, and perhaps for some degree of wanton
and boastful exaggeration, there will remain enough to carry
them nearly to the extremity of Asia; and it will remain quite
unaccountable, how any period approaching to the above, could
be spent in travelling to a place which could not be farther
distant than five or six hundred miles.

If the distance and direction correspond thus ill, the deserip-
tion is, if possible, still more discordant. So far was Protemy
from the remotest idea of Sera being in India, or near the
Ganges, that he fixes it about forty degrees, nearly half the
length of Asia, east from that river. The most profound igno-
rance of this quarter of India would be necessary to account
for so unheard of an error. On the contrary, we have found
this region, which gives rise to the Ganges and its tributaries,
to be one of those in which Protemy has displayed the most
decided superiority to modern information. In representing
the heads of the Ganges by the rivers of Serica, Protemy
would have committed a very extraordinary error indeed ;. for
these run south-west, while the others are made to run north-
east ; a change of direction quite unheard of, With regard to
the geographical relations of Serica, it is needless to mention
them, as it is evident that all these, by the present —_
must be entirely thrown up.

This system, like the other, rests solely, I apprehend, signa
nominal arguments. Some writers mention Serinda, or India
Serica, a country in the north of Indostan, which actually pro-
duced silk, the staple of Serica. What is more, there are two,
Stephen of Byzantium, and the anonymous geographer of Ra-
venna, who appear to consider this as the Serica, and the Seres

as

OF CENTRAL AND EASTERN ASIA. 199

as Indians. In order to estimate these authorities, however,
we must consider their dates. It is not till two or three cen-
turies after Priny and Protemy, that the name of Serindi oc-
curs; nor is it till the sixth and eighth centuries, that these
come to be confounded with the Seres. The decline of the
Roman empire, and the irruption of the Turcoman hordes,
broke off this grand Jine of commerce across Asia; silk, then,
which had become the luxury of all ranks, was again sold for
its weight in gold. The consequence was, that the geography
of this part.of the world, more than shared the general eclipse
in which all branches of science were involved. Of this, the
statements of the Ravenna geographer afford the clearest evi-
dence. He evidently knew nothing of the coast of India be-
yond the Ganges ; and the appellation of India Serica compre-
-hends, with him, not, only the whole interior of Indostan, but.
the whole of Central and Eastern Asia, to Bactriana inclusive.
It is clear, therefore, that he viewed those regions in the man-
ner natural to ignorance, as a dim and indistinct mass, the fea-
tures. of which were all blended together. In regard to other
parts of the world, that were at all remote, he displays errors
that belong only to the infancy of science. He makes the Cas-
_pian.a gulf of the Northern Ocean ; he extends Britain entire-
ly from east to west, making one extremity border on Norway,
and the other on Spain. His age seems therefore to be cha-
racterised. by the almost total extinction, as to all remote re-
gions, of those geographical lights which had shone upon the
age of Puiyy and Proremy ; and in preferring his authority to
_ theirs, M. Gossexi prefers, if not darkness, at least deep twi-
light, to the light of day. ,
With regard to the origin of the name Serinda, it does not
_ appear, very difficult to trace. Serica was known to the an-
cients as the country of silk; that substance itself was called
sericum.

————

—_———_

200 ON THE ANCIENT GEOGRAPHY

sericum. When, in consequence of interrupted commerce, the
empire laboured under the want of this luxury, intelligence
was brought, that it was produced in a region to the north of
India, from whence, in fact, the silk-worms were transported
to Europe. That region might then be very naturally called
India Serica or Serinda, changed by the Mahommedan conque-
rors to the Arabic term of Sirhind. But M. Gossexin himself
remarks, that the very names of Serinda and India Serica im-
ply that there is another Serica, and other Seres. These he
finds on the other side of the Ganges, in Serinagur, a place
which certainly presents a somewhat curious coincidence of
name. Nagur being a common appendage to Indian names of
places, and signifying chief city, Serinagur represents almost
exactly the Sera Metropolis of Proremy. I must confess, that
I have nothing to oppose to any one who should conceive the
coincidence of a single name suflicient to invalidate all the ar-
guments on the other side which have now been stated. I
shali only add, that M. Gossgt1n’s ideas of the territory of Se-
rinagur, are entirely derived from those erroneous views which
have been dissipated by the expedition to the source of the
Ganges ; the result of which, though known in this country,
does not seem to have reached him previous to the publication
of his last volumes. He mentions Serinagur as situated among
the frontier mountains, and even stretching into Thibet. He
is evidently not aware, that it is entirely enclosed within the
great mountain wall of India. Captain Rarzr and Mr Wess
notice, that on ascending a hill in its vicinity, they found
themselves indeed raised to a great height above the plain of
India; but on turning northward, they beheld with amazement,
and almost with terror, a long succession of ranges rising over
each other, while high above all, towered the eternal snows of
Himalaya. That commerce should take its course across this

barrier

=

OF CENTRAL AND EASTERN ASIA. 201

barrier of ice and desolation, when an easy and level route ex-
isted to the coast, then crowded by western navigators, is sure--
ly not very probable.

In 1802, Serinagur was visited by Captain Harpwicke, who
has given a description of it, which is confirmed by Captain
Raver and Mr Wess. They represent it situated in a valley,
extending about a mile and a half in every direction; the city
itself three quarters of a mile in length, and about half that
breadth ; the houses poor, and the streets so narrow, that two:
persons could scarcely walk abreast. There was scarcely a
mansion fit for the residence of a provincial Rajah ; no splen-
did ruins, no monuments of antiquity ; nothing which could
recal the splendor of that mighty metropolis, whose ‘fame was
so widely diffused over the ancient world.

From the whole of what has. been said, it. seems to follow,
that the interpretation now proposed, is that which naturally
arises out of the statements of Protemy. If it be admitted as
true, his delineation will still, indeed, present imperfections
and errors of detail; but, in all its leading features, it will be
found correct, consistent with itself, and with the actual fea-
tures of the region delineated. Upon the other suppositions
now prevalent, it forms confessedly a mass of the most enor-
mous errors that ever were committed by any geographer. Be-
tween these two alternatives, there could scarcely, in any case,
be room for hesitation. It can be added, however, that Pro-
LEMy is not only a writer generally of good authority, but that
he has shewn himself to possess, in respect to a long series of
conterminous regions, better information than had, till very re-
cently, been attained by the moderns. I submit, then, «to
the learned, whether credit should be refused to his delinea-
tion of those ulterior regions, with regard to-which also he pro-
bably had access to better materials than have yet fallen to the
lot of modern inquirers.

Vou. VIII. P. I. Ce POST-

202 ON THE ANCIENT GEOGRAPHY

POSTSCRIPT.

Since the above was printed, I had an opportunity of sub-
mitting it to Dr Francis Bucuanan, whose extensive re-
searches into the history and geography of India are already
well known to the public, and will, we are happy to learn, ap-
pear in future publications. A long residence in Nepaul af-
forded him peculiar opportunities of collecting information re-
specting the countries bordering on the northern frontier of In-
dia. I was gratified to find, that he entirely concurred in the
general views contained in this essay, and even attached less
importance than I myself had done, to some of the objections
which may be made to them. He was so obliging as to com-
municate the following additional and corrective information
on several important topics.

I have stated my suspicion, that the river reported to the
Chinese Lamas as the Ganges, was in reality the Indus. From
Dr Bucuanan’s information, however, I cannot doubt that it
is the Sutledge, or, more properly, Satadru (Zaradrus of Pro-.
Lemy,) which rising from the lake Manas Saroer, crosses the
Snowy Chain, and rolls through the Punjaub into the Indus.
Dr Bucuanan is also of opinion, though it is otherwise repre-
sented by Mr Arrowsmitu, that the Gogra rises from a lake
near the Manas Saroer, and crosses the Himalaya.

Dr Bucnanan is convinced, from positive information, of
the existence of the Chain of Mountains separating Great from
Little Thibet, which I have supposed to be the Northern
Imaus of Protemy. It appears in the most recent map of Mr
ArrowsmitH, under the name of Mount Caillas, at precisely
the same distance east from the source of the Ganges, that
Protemy has placed his bend of the Imaus; and contains on
its opposite sides the sources of the Barrumpooter (properly

Bramapoutra,)

I aE ” 5 at ari

OF CENTRAL AND EASTERN ASIA. 203

Bramapoutra,) the Satadru, and the Ladauk, which is evident-
ly the largest’ branch of the Indus. Mr ArrowsmitH has ex-
tended it along the western bank of the Ladauk ; but Dr Bu-
CHANAN has every reason to believe, that it stretches along the:
opposite side, and unites itself to the Mooz Taugh, forming a
complete barrier between Great and Little Thibet. Whether
or how far it extends northward, in the direction indicated by
Protemy, modern geography does not afford the means of as-.
certaining. Dr Bucuanan is disposed to view it as a prolon-
gation of the Mooz Taugh, turning southwards, and uniting
with the Himalaya. ‘This is evidently little more than a no-
minal distinction from the opposite view of Protemy, in ma-
king it a continuation of the Imaus northward.

Under Dr Bucwanan’s direction, I have ventured to lay
down the chain of mountains in question according to his idea
of their course ; also the sources of the Bramapoutra, Ladauk,

’ Satadru and Gogra.

Dr Bucuanan is of opinion, that the representation of Chi-
na as a country of mountains would not be so wholly incorrect
as I have supposed. He conceives, that the lofty chain sepa-
rating Canton from the northern provinces, and which was
crossed by Sir Grorcr SravnTon, is a prolongation of the Hi-
malaya. This would make Protemy correct, in extending
that chain, under the name of Ottorocoras, to the extremity of
the known world. The western provinces of the empire are
also in general mountainous.

Dr Bucuanan attaches no importance to the name of Seri-
nagur, (properly Sreenagur, the Holy City,) as he knows its
foundation to be entirely modern, and not to reach back above
two or three centuries.

The ancient Map is copied from those usually appended to
Protemy’s Geography, unless in a few instances, where these
appeared to differ from the ‘text, which is universally allowed
to be of higher authority,
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Beek We mo Se at

XI. An Analysis of Sea-Water ; with Observations on the Ana-
lysis of Salt-Brines. By Joun Murray, M. D. F.R.S. E.

(Read 15th April, and 20th May, 1816. )

HE composition of Sea-Water has been variously sta-

ted by different chemists, not only with regard to the

peahradtisih of the salts which it holds in ews but with re-
gard even to the ingredients themselves.

According to Lavorsrer, it contains muriate of soda, muriate

_of magnesia, and muriate of lime, sulphate of soda, sulphate

of magnesia, sulphate and carbonate of lime. The pro-
portions he assigns are, in'a pound of water, (French weights)
126 grains of muriate of soda, 14% grains muriate of magnesia,
23 grains muriate of lime mixed with muriate of magnesia,
7 grains of sulphate of soda and sulphate of magnesia, and 8
grains of sulphate and carbonate of lime *.

BereMan gives a very different statement. He found only
muriate of soda, muriate of magnesia, and sulphate of lime;
the proportions in a Swedish kanne, which is equal to about 64
English pints, are 2 ounces 433 grains of muriate of soda, 380

) grains

“* Memoires de Academie des Sciences, 1772.

206 AN ANALYSIS

grains of muriate of magnesia, and 45 grains of sulphate of
lime *. Reducing them to English weights, they are equal, in
a pint of water, to, muriate of soda 241 grains, muriate of mag-
nesia 65.5, sulphate of lime 8. This, however, is with regard
to water from the Canaries, containing 1 part of saline matter
in about 231 of water. Reducing it to the proportion of the
water of our shores, that of about 1 to 30, the proportions will
be, muriate of soda 186.5, muriate of magnesia 51, sulphate of
lime 6 = 243.5 grains.

Bereman’s analysis is evidently incorrect in the omission of
sulphate of magnesia, which every other chemist has obtained,
and which is known to be extracted even on a large scale.
And, what is singular, this did not arise from his not being
aware that it might be present. On the contrary, he made an
experiment to discover it ; and even now, in reviewing his me-
thod, it is not apparent how he had been deceived. He eva-
porated to dryness, and treated the dry residuum with alcohol,
by which he found muriate of magnesia to be dissolved; he
then washed the residual matter, consisting chiefly of muriate
of soda, with a small quantity of warm water, by which, as he
remarked, if any sulphate of magnesia were present, it ought to
have been dissolved. But this water shewed no signs of the
presence of this salt, either in taste or by precipitation, and
contained nothing but a small portion of common salt. Now
unquestionably, in this way, sulphate of magnesia ought to
have been discovered ; or if it should be supposed that it does
not originally exist, but that sulphate of soda is the primary
ingredient, still the method employed was equally proper to
discover this latter salt. The only supposition that can be
made is, that, in the first step of the analysis, a very weak alco-

: hol

* Beroman’s Essays, vol. i. p. 230.

ae

OF SEA-WATER. 9207

hol had been used in large quantity, by which a portion of
these sulphates would be dissolved, though still it is difficult
to imagine that in this way they would be entirely abstrac-
ted.

Lavoister’s analysis has been considered as incorrect in two
circumstances,—in the finding muriate of lime and sulphate of
soda. Neither of these have been discovered by other che-
mists ; and in a late analysis of sea-water by Vocrt and La-
GRANGE, one of the objects of experiment was to detect their
presence, and the conclusions drawn were, “ that sea-water
“‘ contains no sulphate of soda,” and “no muriate of lime.”
In this analysis the saline ingredients found in sea-water were
the same as those assigned by Berean, with the addition of
sulphate of magnesia. In 1000 grammes there were found 25.10
grammes of muriate of soda, 3.5 of muriate of magnesia, 5.78 of

~ sulphate of magnesia, 0.20 of carbonate of lime and magnesia,

and 0.15 of sulphate of lime *.

Some other recent analyses have been given; that by Licn-
TENBERG is noticed by VocreL and Lacrance, from a German
Journal, as approaching to’ their own; and that of Prarr, in
which, as in Lavoisrer’s analysis, there is found a portion of
muriate of lime.

It is obvious, that there remains a degree bf uncertainty with
regard to the ingredients of sea-water, sufficient to give interest
to a new analysis. The principle, too, which I have illustrated
in a preceding paper, on the analysis of Mineral Waters,—
that the substances obtained are not always to be regarded as
the original ingredients, but frequently as products of new
combinations established by the analytic operations, may con-
tribute to throw light on the conclusions to be drawn, and

seemed

* ‘Tuomson’s Annals, vol, iv. p. 200.

208 AN ANALYSIS

seemed to me to admit of being applied to the explanation of
some of the preceding results. This led to the experiments of
which I now propose to give an account.

The peculiarity in the results of Lavorsrer’s analysis, and
with regard to which the others differ from him, is the obtain-
ing, as ingredients of sea-water, portions of sulphate of soda
and muriate of lime. Applying the principle now referred to,
it is obvious, that in an analysis by evaporation, the composi-
tion of these salts would be subverted by their reciprocal ac-
tion ; neither of them would be obtained ; but by mutual decom-
position they would be converted into muriate of soda, and
sulphate of lime. Sulphate of lime is accordingly obtained in
all these analyses, and probably has this origin.

But, admitting this, how had muriate of lime, and sulphate
of soda, been procured by Lavorsrer. This, supposing the re-
sult accurate, can only be ascribed to some peculiarity in his
process, by which their mutual action had been prevented, and
their distinct existence preserved. The method he employed
was to evaporate sea-water to dryness ; during the evaporation,
sulphate and carbonate of lime were precipitated and were
withdrawn ; the dry saline mass was lixiviated with alcohol ;
and the ley being poured off clear, was found to hold in solu-
tion muriate of magnesia, and muriate of lime; the undissol-
ved matter was then heated, with a mixture of two parts of al-
cohol and one of water, by which it was almost entirely dissol-
ved ; it deposited, however, on cooling, a white powder, which
was found to be sulphate of soda, and sulphate of magnesia,
and it retained dissolved the muriate of soda of the sea-water
with a portion likewise of muriate of magnesia.

Now a portion of sulphate of lime was obtained in this pro-
cess, which, according to the view I have stated, was probably

produced

OF SEA-WATER. 209

produced by the mutual decomposition of sulphate of soda and
muriate of lime. But it is also possible, that this decomposi-
tion might not be complete. I had formerly found, indeed,
that when a liquor containing these two salts is evaporated,
their decomposition is not entirely effected *; it seemed pos-
sible, therefore, that portions of both might remain undecom-
posed in Lavoisier’s process; the alcohol applied to the solid
matter would remove the muriate of lime, and thus the sul-
phate of soda would remain. To elucidate the whole subject,
therefore, it seemed. best to repeat LavoisiEr’s analysis as he
had performed it, and ascertain the actual results,

A. Four pints of sea-water of the Frith of Forth, taken up
near Leith, at a distance from any fresh water, were evapora-
ted by the heat of a sand-bath ; the evaporation being continu-
ed until a pellicle of salt formed on the boiling liquor. A pre-
cipitate subsided during the boiling, which being washed,
weighed when dry 25 grains.

B. The liquor was evaporated to dryness, and the saline mass
was dried thoroughly by a continued heat of about 150° ; it
weighed 1025 grains. To separate the salts composing it, it
was submitted to the action of alcohol. About 4 ounces of alco-
hol of the specific gravity of 840 were poured upon it.in a
bottle, and allowed to remain over it for 12 hours, being occa-
sionally agitated; and when poured off an ounce of the same
alcohol was added, and after frequent agitation, and being kept
_ oyer it for some hours, was poured off, and added to “ithe for-
THER hysy anys t: gris cil an

C. The. residuum, aM risibgs asieiaia 890 tininisyaid 96
grains had mreraline been abstracted, consisting maa of earthy,
mutiates. faliiues it’ Indoeauspiloh

Vou. VILL P. L puri: d ; D. The

* Transactions, Vol. vii p. 475.

210 AN ANALYSIS

D. The saline matter was digested with 9 ounces of a weak-
er spirit, composed of 2 of alcohol and | of water, heat being
applied to it by a sand-bath nearly to ebullition, with frequent
agitation; and the liquor having been poured off while hot,
4 ounces more of the same diluted alcohol were added, heated
as before, and after it had become clear by subsidence, this li-
quor was added to the other. The greater part of the saline
mass, consisting chiefly of muriate of soda, was thus dissolved.

E. The residue was submitted to the action of successive
quantities of a still weaker spirit, composed of 3 of alkohol, and
4 of water, aided by heat, with the view of dissolving the sul-
phate of magnesia and of soda. A solution was obtained of a
strong saline taste.

F. To abstract these salts more completely, the residue was
lixiviated with small successive portions of warm water ; a so-
lution having a similar taste was obtained.

G. There was left at length a powder, soft, light, tasteless,
and insoluble.

It now remained to examine these products more minutely,
to determine their nature, and estimate precisely their quanti-
ties.

The powder obtained in the first evaporation A, consists,
according to Lavorster, of sulphate and carbonate of lime. It
weighed when dry 25 grains ; it was submitted to the action of
a very dilute alcohol, acidulated with muriatic acid, which ex-
cited effervescence ; this being poured off, and the residue be-
ing lixiviated, and dried, weighed 22 grains. It was sulphate
of lime, and absorbed water with avidity, becoming solid and
dry. The liquor poured off, afforded by evaporation a saline
deliquescent matter, which, heated with sulphuric acid, gave

products

Nae

OF SEA-WATER, 211

products equivalent to 1.7 grains of carbonate of magnesia, and
1.2 grain of carbonate of lime.

The solution (B) obtained by the action of the stronger al-
cohol, ought to have contained, according to the results of La-
vorsiEr’s analysis, muriate of magnesia and muriate of lime.
A small portion of it was diluted with distilled water, and a
few drops of a solution of oxalate of ammonia were added, but
caused, no precipitation, nor eyen any opacity. The liquor,
therefore, contained no muriate of lime. It was distilled to
dryness. The dry matter deliquesced on exposure to the air ;
being lixiviated with alcohol, a small portion of muriate of so-
da remained undissolved, which was added to the solution D.
The liquor being evaporated so far as to be of an oily consist-
ence, afforded, on cooling, muriate of magnesia in prisms. This,
dried until it had no appearance of moisture, weighed 145
grains. Decomposed. by sulphuric acid, it afforded 105.9 grains
of dry sulphate of magnesia, equivalent to 88.5 of real mu-
riate.

The solution D had a strong saline taste, and, in cooling,
had deposited muriate of soda in cubes on the sides of the
bottle. A little of it being diluted with distilled water, oxalate
of ammonia did not impair the transparency. Carbonate of
potash, and muriate of barytes, produced a turbid appearance.
The entire liquor was submitted to distillation, until the alcohol

_ was abstracted, and was then evaporated in an open bason, un-

til crystals formed in it while hot. These were cubes of mu-
viate of soda, and this salt continued to be afforded by succes-
sive ‘evaporations. The last product deliquesced a little on
exposure to the air, indicating the presence of muriate of mag-

_nesia ; and the remaining liquor afforded by evaporation a deli-

quescent saline mass: both these were washed with repeated

- portions of alcohol ; muriate of magnesia was thus obtained,

Dd2 which

212 AN ANALYSIS

which dried, weighed 17:3 grains, and which, converted into
sulphate, gave 12.4 grains, equivalent to 9.7 of real muriate.
The matter not dissolved by the alcohol, being dissolved in wa-
ter, afforded by slow: evaporation sulphate of magnesia in
prisms, which dried, weighed 6.3 grains. The crystallised) mu-
riate of soda, dried at a heat of 200°, weighed 580 grains. «

The solution E deposited, on standing after twelve hours, ery-
stals in flat striated prisms, having every appearance of sulphate
of soda, and which, on more minute examination, were found
to be so: freed from sensible moisture, they weighed 18 grains.
The liquor diluted with distilled water, was not sensibly affect-
ed by oxalate of ammonia; it became slightly turbid with sub-
carbonate of potash, and with muriate of barytes. The alcohol
was drawn off by distillation ; being then submitted to evapo-
ration, a crust of muriate of soda formed on the surface, and
crystals in cubes were deposited ; additional portions of them
were obtained by successive evaporations, and the liquor conti-
nued to afford a crust of muriate of soda on its surface, while
hot, until it was almost entirely evaporated. A small por-
tion of liquor remained, which, on cooling, afforded prisma-
tic crystals of sulphate of magnesia, which, freed from moisture,
weighed 8.9 grains. The muriate of soda dried weighed 170.8
grains.

The first portions of the aqueous solution F had deposited
crystals of sulphate of soda on cooling ; and the whole quanti-~
ty being partially evaporated, yielded an additional portion.
The crystals of both, freed from adhering moisture, weighed
44.2 grains. The liquor being farther evaporated, cubes of
muriate of soda were formed on the sides of the capsule, while
it was warm, and by continuing the evaporation, a quantity of
this salt was obtained, which weighed when dry 12.3 grains.

oa

bs
h
r

= ta a a cS <a

—— 4.7"

SPIER IE OE e T

4 ee

OF. SEAWATER. 213

Ajsmall portion of liquor remained, which, by farther: evapora-
tion, yielded crystals of ‘sulphate’ of soda‘ to: the: amount of 6
grains, with crystals‘of muriate of soda 2 grains.

The portions of muriate of soda obtained in the deseditn
experiments amounted’ to’ 765.1 grains... None of them; how-
ever, were perfectly | pure. ° Their solutions became turbid om
the addition of sub-carbonate of soda, and of muriate of ba-

_ rytes, indicating the presence of sulphate of magnesia, or of

muriate of magnesia and sulphate of soda, and probably. indeed
of portions of all these. “The whole was submitted to the ac-
tion of highly rectified alcohol for 12 hours, with repeated agi-
tation ; the alcohol acquired-a bitter taste ; being poured off,
and distilled, it afforded muriate of magnesia, which, heated
with sulphuric acid, gave a product equivalent to 6.2‘of real
muriate. The residual salt still gave indications of the pre-
sence of sulphate of magnesia, by the tests of muriate of ba-
rytes and sub-carbonate of soda. The difficulty is so great, of
separating a small portion of a salt from a large quantity of
another, where the difference in their solubility is not consider-
able, that instead of attempting to remove the sulphate of mag-
nesia by farther crystallizations, it was decomposed by adding
to the solution sub-carbonate of soda; the precipitate was col-
lected, and converted into sulphate of magnesia by the addition
of sulphuric acid. This, dried ata low red-heat, weighed 16
grains, equivalent to 33 crystallised. The salt had been previ-
ously exposed to a red-heat, when it weighed 744.5 grains.
The above quantity of sulphate abstracted from this, leaves as
the real quantity of muriate of soda 728.5 grains.

The powder G was soft, light, and tasteless. It weighed
when thoroughly dried 7.5 grains." It might be expected to be
similar to the powder A, and was therefore subjected-to the
same treatment. Diluted alcohol, acidulated with muriatic

acid,

214 AN ANALYSIS

acid, excited effervescence ; the liquor poured off afforded by
evaporation muriates equivalent to 2.8 of carbonate of magne-
sia, and 1.3 of carbonate of lime. And the remaining sulphate
of lime dried weighed 3 grains.

By this analysis, then, the substances obtained from 4 i
of sea-water, and their proportions, are as follow :

Muriate of Soda, - - 728.5 grains.
Muriate of Magnesia real, 83.5
9.7
6.2
99.4 99.4
Sulphate of Magnesia crystal-
lised, - - 6.3
8.9
33

48.2, or real, 23.5
Sulphate of Soda crystallised, 18
44.2
6

68.2, or real, 30.2
Sulphate of Lime, real, 22

25 25
Carbonate of Lime, 2 12

2.5 2.5
Carbonate

A egypt OO LIL Pa PEACE

OF SEA-WATER. 215

, Carbonate of Magnesia, he i
2.8

——

4.5 es

The two last ingredients might be accidental products, from.
the decomposition of muriate of magnesia and of lime. Mu-
riate of magnesia is decomposed by heat ; a portion of its acid
is expelled ; and the magnesia separated in consequence of this,
will absorb carbonic acid, from the current of warm air applied
during the evaporation, or from the carbonic acid gas which the
sea-water itself contains, and which is not immediately expell-
ed by heat. The small portion of carbonate of lime might be
produced in a similar manner, or from the action of the carbo-
nate of magnesia on muriate or sulphate of lime. I according-
ly found, in a subsequent analysis, that on adding muriate of
barytes to sea-water, no carbonate but only sulphate of barytes
is precipitated, which proves that these conclusions are just.
For the small portion, therefore, of carbonate of magnesia, the
equivalent portion of muriate of magnesia, 4.2, raising it to
103.6, is to be substituted. Ifthe lime which afforded the car-
bonate existed in the state of sulphate, then the equivalent por-
tion of this 3.4 is to be added to the sulphate actually obtain-
ed, making it 28.4. If it existed in the state of muriate of
lime, it still would, but for this change, have been converted in
the progress of the evaporation into sulphate of lime; the same
substitution, therefore, is in this view equally to be made.
With these corrections, and reducing the proportions to a pint,
the ingredients and their quantities wil! be as follow:

Muriate of Soda, - —-- 182.1 grains.
Muriate of Magnesia, ~ 25.9
Sulphate of Soda, - 7.5
Sulphate of Magnesia, - 5.9
Sulphate of Lime, 3 rei

228.5

The

216 AN ANALYSIS

The results of the preceding analysis are different from those
I had expected to obtain. I had supposed, that in Lavoisrer’s
method, the sulphate of soda, and muriate of lime, which he
stated as ingredients, had been obtained from some peculiarity
in the process by which their reciprocal action, and consequent
transition into muriate of soda and sulphate of lime had been
prevented; and that in the common method of evaporation
they are not obtained, because this mutual decomposition takes
place. It appears, however, that the results by Lavorsrer’s
method are different from those he stated, and are such as pre-
clude this view. No muriate of lime is obtained, and sulphate
of lime is obtained in considerable quantity; of course, the
sulphate of soda, which is also found, cannot be considered as
being procured, in consequence of its decomposition by muri-
ate of lime being prevented by any peculiarity in the process,
and must therefore be ascribed to some other cause.

Besides the peculiarity in this analysis of sulphate of soda,
there is another singularity in the result, that little sulphate of
magnesia is procured. This salt, it is well known, is extracted
in considerable quantity by the common process of evaporation
of sea-water on a large scale, being obtained by boiling down
the bittern, while, by this method, little or no sulphate of soda
is obtained.

The products of this analysis are thus so different from those
usually assigned, and so different from those known to be af-
forded by the usual process of evaporation, that it became de-
sirable to perform the analysis in the common mode, so as to
ascertain the actual results of it with precision, with a view to
determine on what these differences depend. This I accord-
ingly executed.

A. Four pints of the same sea-water were submitted to eva-
poration in a sand-bath, and_after the crystallization of the mu-
riate

i 4
. AnH

Sac TEAS oe tr OR

OF SEA-WATER. 217

riate of soda commenced, the liquor was poured off at intervals

. from the salt deposited, and farther evaporated. This was con-

tinued as long as it appeared to afford no other salt on cool-
ing than muriate of soda. The latter products of this salt were
less pure than the first, being deliquescent on exposure to a
dry atmosphere ; they were therefore redissolved in water ; by
evaporation, the greater part was obtained crystallized, in a pu-
rer state, and was added to the other; and the small portion
of residual liquor was added to the residual liquor of the eva-
porated -sea-water.

B. By farther evaporation, this liquor afforded crystals in
slender prisms, which were permanent in the air, and which
were found to be sulphate of magnesia; by repeated evapora-
tions, successive crystallizations of this kind were produced,
(small portions of muriate of soda being also obtained, which,
after being washed, were added to the salt A) ; the products of
the first crystallizations were nearly pure ; those of the latter
crystallizations were less distinct in form, and were in part de-
liquescent.

C. The. portion of liquor still remaining was evaporated,
until, on cooling, it formed a congeries bre slender prisms,
which, exposed to the air, deliquesced, and soon passed to a
state of perfect solution, a proof of their bens principally mu-
riate of magnesia.

The products thus obtained, consisted, first, of muriate of so-
da A; secondly, of sulphate of magnesia B; and, thirdly, of
muriate of magnesia C. These, however, could not be suppo-
sed to be pure, and they were, therefore, submitted to farther
examination.

D. The muriate of soda A, gave indications of the intermix-
ture of magnesian salts; the solution of a minute portion of
it in distilled water becoming turbid on the addition of carbo-

Vox. VIII. P. I. Ee nate

218 AN ANALYSIS

nate of soda. It was also to be presumed, that there would be
mixed with it any sulphate or carbonate of lime deposited du-
ting the evaporation. It was therefore re-dissolved in water.
There remained undissolved a residue, which, when thorough-
ly dried, weighed 22.6 grains. The salt was again procured
by evaporation, but it was still not perfectly pure. Its dilute
solution gave a milkiness with carbonate of soda; and oxalate
of ammonia and muriate of barytes rendered it turbid, indica-
ting the presence either of a little muriate of lime with sul-
phate of soda, or magnesia, or of sulphate of lime with a por-
tion of sulphate or muriate of magnesia. ‘The whole was re-
dissolved in distilled water, a powder similar in appearance to
the insoluble residue of the former solution, remained undis-
solved, which, when thoroughly dried, weighed 10.3 grains.
To the clear solution a portion of alcohol was added, not suffi-
cient to cause any precipitation of muriate of soda; it produ-
ced a slight turbid appearance, and after some hours a powder
had subsided, which, after being washed with water, was
tasteless : it weighed 1.5 grains. The muriate of soda, obtain-
ed by evaporation, weighed, when dried, 718 grains. Being

still not entirely pure, it was reserved for another operation.
E. The insoluble residues collected in. the preceding opera-
tions being put together, were submitted to the action of alco-
hol, acidulated with muriatic acid, to remove any carbonate of
lime, or of magnesia. Effervescence was excited ; the liquor
being poured off, and the insoluble residue of sulphate of lime
being washed with a little water, weighed, after exposure to a
heat nearly equal to ignition, 26.3 grains. The alcoholic so-
lution, with the addition of the small portion of water with
which the sulphate of lime had been washed, afforded, by eva-
poration, a matter which entered readily into fusion, and
which, treated with sulphuric acid, gave 5.6 of sulphate, equi-
valent

OF SEA-WATER. 219

valent to 4.3 of carbonate of magnesia, and 3 of sulphate,
equivalent to 2.2 of carbonate of lime. I have already obser-
ved, however, that no carbonic acid is detected in sea-water by
the test of barytes; these carbonates, therefore, are, as before,
to be considered as products of the evaporation, arising from
the decomposition of muriate of magnesia, and of muriate or
sulphate of lime. The one, but for the decomposition by
which it is produced, would have appeared as sulphate of lime ;
it increases, therefore, the proportion of that ingredient to 29.3
grains. .The portion of muriate, equivalent to the other, that
is, 4.4 grains, may be added to the quantity of that salt obtain-
ed in the subsequent steps of the analysis.

F. The products of the different crystallizations B, con-
sisting chiefly of sulphate of magnesia, with portions of mu-
riate of magnesia, were left. exposed to the air for some days,
and the liquor formed from them by deliquescence, was pour-
ed off occasionally, and added to the solution of muriate of
magnesia, C. The residues were then washed with pure al-
cohol, to abstract more completely any muriate of magnesia.
The portions remaining undissolved, were dissolved together
in water. By evaporation, they afforded sulphate of magnesia
in bevelled prisms ; by farther evaporation, muriate of soda in
cubes was obtained; and by successive evaporations, there
were thus procured. sulphate of magnesia in crystals, 46.6
grains ; and muriate of soda 39 grains. A small portion of li-
quor remained, which, containing chiefly muriate of magnesia,
was added to the liquor C.

_G. This liquor C to which the portion on liquor ai by
deliquescence from B, had also been added, was evaporated
to dryness. It was then submitted to the action of successive
portions of alcohol, employing, first, the alcohol with which
the saline matter B had been lixiviated, and afterwards pure al-
dhol Ee 2 cohol.

220 AN ANALYSIS

cohol. These liquors, poured off from a portion which remain-
ed undissolved, were evaporated to dryness ; the dry mass was
dissolved in water, and, by a second evaporation, afforded a
congeries of prisms of Muriate of Magnesia. Dried by a heat
of 150°, the weight amounted to 156 grains. Converted into
sulphate of magnesia by the addition of sulphuric acid, the
product weighed, after being dried at a low red-heat, 99.2
grains, equivalent to 78.4 of real muriate of magnesia.

H. The matter which remained undissolved by the alcohol
G was dissolved in distilled water. The solution was evapo-
rated, until, by a farther spontaneous evaporation in a warm
apartment, crystals were successively formed ; these were sul-
phate of magnesia, and, in general, bevelled prisms. The
whole freed from moisture weighed 48.6 grains. A small por-
tion of liquor remained, which, when evaporated, gave a deli-
quescent saline mass: by slow evaporation 2.6 grains of muri-
ate of soda were obtained from it ; the remainder alm mu-
riate of magnesia equal to 3 grains.

I. The crystals of sulphate of magnesia obtained by the
successive evaporations, were not all equally well formed ; and
after they had been left exposed to a dry air for some doe
some of them became quite efflorescent, while others did not.
The former were picked out, and each portion was re-dissolved
in water. By a new crystallization, there were thus obtained
72 grains of sulphate of magnesia, and 18.5 of sulphate of
soda.

K. The muriate of soda obtained in the preceding steps,
amounted in all to 759.6 grains. After exposure to a red-
heat, it weighed 752.4 grains. It has already been stated,
that it was not perfectly pure; its solution being rendered
milky, both by sub-carbonate of soda and muriate of barytes.
The separation of the sulphate of magnesia, which this chiefly

indicated,

4

OF SEA-WATER. 221

indicated, was not to be completely looked for by solution and

_ crystallization. Sub-carbonate of soda was therefore added to
. the solution as long as any precipitation took place ; the preci-
_ pitate heated with a sufficient proportion of sulphuric acid to

redness, gave 16.4 sulphate of magnesia, equivalent to 33.7 of
the same salt crystallised. The former quantity abstracted:
from the weight of the muriate of soda, reduces it to 736
grains.

This analysis, then, affords the following ingredients, and:
their proportions in their real state..

Muriate of Soda, - 736 grains.
Muriate of Magnesia, - 85.8
Sulphate of Magnesia, = - 51.2.
Sulphate of Soda, - 8
Sulphate of Lime, - 29.3.

Or, reducing them to a pint of the water,

- Muriate of Soda, - 184 grains.

Muriate of Magnesia, — - 21.5

cnt | Sulphate of Magnesia, - 12.8
Sulphate of Soda, - 2

Sulphate of Lime,. - 71.3

2277.6.

pe ' |
_ By the two modes of analysis now stated, different results
‘have been obtained. There are common to both as the prin-
cipal products, Muriate of Soda, and Muriate of Magnesia.
But in the one, sulphate of magnesia, with only a small: pro-
portion of sulphate of soda, are procured. In the other, sul-
by phate

222, AN ANALYSIS

phate of soda in a much larger quantity, with only an inferior
proportion of sulphate of magnesia, are obtained. How is this
diversity of result to be accounted for ?

As the relative quantities of these salts are thus varied, and.
are indeed nearly altogether dependent on the kind of analy-
sis, it is obvious that one or other of them must be an origi-
nal ingredient, and the other must be a product of decomposi-
tion. If sulphate of magnesia is the original ingredient,
then, when it is not obtained, or is obtained only in very in-
ferior quantity, while sulphate of soda is procured in its place,
it must be held that it is decomposed ; and the only decompo-
sition that can account for these results is that from the mutual
action of muriate of soda and sulphate of magnesia, by which,
while portions of them are removed, corresponding portions
of sulphate of soda and of muriate of magnesia are formed.
On the other hand, if sulphate of soda is the original ingredi-
ent, then, when it is not obtained, or is obtained only in small
quantity, it must be held that it is decomposed ; and the only
decomposition of it that can here take place, must be from the
action of muriate of magnesia, by which, while quantities of
both these salts are removed, corresponding quantities of sul-
phate of magnesia and muriate of soda will be produced.

Of the two analyses, the one in which sulphate of soda prin-
cipally is obtained, is that in which the solvent action of alco-
hol is employed ; the other, in which there is the mere sepa-
ration of the salts by evaporation and crystallization, is that
which affords scarcely any of it, but in place of it sulphate of
magnesia. Now, it is to be observed, that in both of these the
preliminary operation of evaporation to dryness is the same.
Since sulphate of soda, therefore, is not obtained by this ope-
ration, it is obvious, that, even on the assumption of its being
the original ingredient of sea-water, it must, in the progress of

the

ao eS

eee RS a aa

OF SEA-WATER. 293

the evaporation be decomposed by the muriate of magnesia,
and converted into the sulphate of magnesia; and hence, in.
the subsequent solvent action of the alcohol, by which it is ob-
tained, it must be re-formed. And, on the other hand, if -sul-
phate of magnesiais the primary ingredient, and is obtained as
such by the evaporation, it remains to be explained, how it is
converted in the subsequent solution by the alcohol into sul-
phate of soda. The whole question, therefore, resolves itself
into the nature of the action of the alcohol, producing sul-
phate of soda; and of this I perceive no other solution than.
that which I have now to illustrate.

The fact, however it is to be explained, or to be reconciled
with the doctrine of chemical attraction giving rise to combi-
nations or decompositions according to the strength with
which it is exerted, seems to be established by an induction
too strict and: extensive to admit of doubt, that these results.
are often determined by the force of cohesion, in such a man-
ner, that in principles acting on each other, those on which:
this force operates most powerfully, in relation to the fluid
which is the medium of action, are combined together. So.
much is this the case, that, as Berruotter has justly remark-
ed, we may, from a knowledge of the solubility of the com-
pounds which substances form, predict what combinations
will be established when they act on each other ; those always
combining which form the least soluble compounds. | So far
the influence of this has been illustrated by this able chemist.
But it appears to me to admit of farther extension, so as to af-
pre a solution of the present question.

If the force of cohesion can so far modify heii attrac-
tion, as to establish among compound salts dissolved i in any
medium, those combinations whence the least soluble com-
pounds are formed, we are entitled, I conceive, to conclude,

that

224 AN ANALYSIS

that the reverse of this force, that is, the power of a solvent,
may produce the opposite effect, or cause the reverse of these
combinations to be established. Suppose muriate of magne-
sia and sulphate of soda to be dissolved in water, and the so-
lution to be concentrated by evaporation, the combinations of
sulphate of magnesia and muriate of soda, being on the whole
less soluble in water, this circumstance of inferior solubility,
or the force of cohesion thus operating, may determine the for-
mation of these, and, accordingly, their formation is found by
experiment to take place. But suppose sulphate of soda and
muriate of magnesia to be dissolved by the aid of heat in al-
cohol so far diluted as to effect their solution, then those com-
binations will not be established which existed in the watery
solution, because, on the whole, sulphate of magnesia, and mu-
riate of soda, are less soluble in alcohol, even in this diluted
state, than sulphate of soda and muriate of magnesia. These
latter compounds will, therefore, remain undecomposed. But
farther, this may give rise, or, rather, must give rise, in confor-
mity to the principle above stated, to the reverse effect ; so
that suppose sulphate of magnesia and muriate of soda to be
submitted to the action of this diluted alcohol, aided by heat,
the solvent power considered, in relation to the reverse ,com-
binations, may cause the change in the state of these com-
pounds, and their transition into muriate of magnesia and sul-
phate of soda.

In the analysis of sea-water, then, by the first of the me-
thods above described, the evaporation may either, if sulphate
of magnesia and muriate of soda are the original ingredients,

‘afford them undecomposed in the solid state ; or, if muriate of
magnesia and sulphate of soda are the ingredients, it may
cause, by the influence of the force of cohesion, the formation

of sulphate of magnesia and muriate of soda. But when the
solid

a

— oe ee.

a eo

a
7”
%

OF SEA-WATER. 295

solid mass is submitted to the action of alcohol, its operation,
as a solvent, may, on the same principle, cause the reverse
combinations to take place, of muriate of magnesia and sul-
phate of soda; the quantity of this sulphate being, of course,
equivalent to the quantity of sulphate of magnesia; and the
quantity of muriate of magnesia formed, being added to the
quantity of that salt which the sea-water contains as a primary
ingredient. Thus is explained the diversity of results obtain-
ed by the two modes of analysis; and this diversity itself af-
fords an excellent illustration of the change of combination
which may be produced in mineral waters by analytic opera-
tions, and a very conclusive proof that the substances obtained
by the analysis are not always to be regarded as the original
ingredients, since here they are varied according to the mode
in which the analysis is performed *.

‘Vor. VIIT. P. I. or LavoisiEr

* The small portion of sulphate of soda obtained with the sulphate of mag-
nesia, in the second analysis, may have been formed by the action of the alcohol,
which, though employed much less extensively than in the first, was still intro-
duced to a certain extent. Or it might originate from other circumstances in-
dependent of this; for a similar result, I have been informed, sometimes oc-
curs in the large way, sulphate of soda being procured in boiling down the bit-
tern of sea-water to obtain its sulphate of magnesia, or in purifying this sul-
phate. The circumstances on which this depends, it may be difficult to assign
with perfect precision ; but it probably arises from the relative quantities of the
different salts, and their tendency to crystallization, as influenced by the state of
concentration, and the temperature. That both of these have a considerable
effect on the combinations established in a compound saline solution, has been
sufficiently shewn by the experiments of Berruotter and others, A striking
proof of it was derived from the very salts which are the subject of the present
observations, in a singular case of affinity, first observed by Scuzeue, and af-
terwards confirmed by Gren: that of muriate of magnesia and sulphate of so-
da, which decompose each other in a concentrated solution at a high tempe-
rature, producing muriate of soda and sulphate of magnesia; but, at tempe-
ratures below 32°, the reverse effect takes place, muriate of soda and sulphate

of

296 AN ANALYSIS

Lavorsrer had stated muriate of lime as having been obtain-
ed in his analysis, being dissolved with the muriate of magne-
sia in the alcohol with which the solid matter obtained by eva-
poration had been lixiviated. I found no trace of it; and its
presence after the evaporation to dryness, does not seem com-
patible with that of either sulphate of soda, or of magnesia.
Yet if the preceding reasoning be just, it is possible that alco-
hol, by its solvent action, might cause its reproduction to a
certain extent from sulphate of lime. On the other hand, the
entire insolubility of sulphate of lime in alcohol, might prevent
it from being acted on; this is even more probable; and the
result stated of muriate of lime being obtained, is therefore, in
all probability, to be ascribed to error, principally perhaps to
its not being distinguished sufficiently from muriate of magne-
sia, the quantity of which is stated by Lavorsrer evidently too
low.

The

of magnesia re-acting, and being converted into sulphate of soda and muriate of
magnesia. This singular case is evidently owing to the relation of the solubili-
ty of these salts to temperature. Muriate of soda has its solubility little increa-
sed by heat, of course little diminished by cold; sulphate of soda is in this re-
spect precisely the reverse ; hence, at an elevated temperature, muriate of soda
is the less soluble salt; and this determines its formation and separation from a
compound solution, containing its elements ; at a low temperature, again, sul-
phate of soda is the less soluble salt; and this equally determines its forma-
tion, of course occasions the reverse decompositions. Now, according to the
proportion of saline ingredients, and according to the state of concentration,
and the temperature favouring the tendency of certain salts to crystallization
more than others; it is easy to conceive, that in a compound solution, different
combinations may be established, as these circumstances vary, and thus products
may be obtained, under certain conditions, which are not obtained under others.
Although sulphate of magnesia, therefore, is usuaily obtained by evaporation
trom sea-water, sulphate of soda, at some stages of the operation or under pecu-
liar circumstances, with regard either to relative quantity of the elements, or to
temperature, may likewise be formed,

OF SEA-WATER. 22%

The question now remains for consideration, What is the real
composition of sea-water ? How far are the salts obtained in
either mode. of analysis, those which exist originally in solu-
tion? This question is evidently to be considered under the
same point of view as that which I have illustrated in a former
paper, with regard to the change in the state of combination,
which may be produced in the saline compounds existing in
mineral waters, by the analytic operations to which they are
subjected. _We have no strict evidence that the binary com-
pounds which are obtained are those which existed in solution,
admitting even the principle that binary combinations exist.
On the contrary, there is every probability, that the substan-
ces obtained are often products of the operation, arising from
changes of combination which it established. And this is
even placed in a more striking point of view in the present
case, as the ingredients obtained are actually different, when
different methods of analysis are employed. It is, therefore,
necessary to inquire farther what the real composition is.

_ With regard to the sulphate of lime, which is the first sub-
stance separated by the evaporation, the general views I have
already stated, give every probability to the conclusion, that
it is a product of the operation formed by the action of sul-
phate of soda or of magnesia during the evaporation, on mu-
riate of lime ; that this last salt, therefore, is an ingredient in
sea-water ; the proportion of it being the quantity equivalent
to that of the sulphate of lime which the analysis affords.
The small portions of carbonates of magnesia and lime
which are obtained in the evaporation, I have already stated,
are evidently accidental products from the decomposition of
muriate of magnesia and muriate or sulphate of lime.
The large quantity of muriate of soda leaves no doubt, if bi-
nary compounds at all exist in a state of solution, that it is the
FfA2 chief

228 AN ANALYSIS

chief ingredient in sea-water, though the quantity of it may be
affected by the changes which occur from the actions of some
of the other salts.

A similar conclusion is to be drawn with regard to the Mu-
riate of Magnesia. Though the proportion of it may be affect-
ed by the changes which occur in the analytic operations, still,
from the quantity in which it is obtained, a considerable part
of it must originally exist.

The principal difficulty is with regard to the sulphate of
magnesia, and the sulphate of soda. It has always been sup-
posed, that sulphate of magnesia is an ingredient in sea-water,
from its being procured by evaporation ; and it is possible that
it may be so. But it is just as possible, @ priori, that sulphate
of soda may be the original ingredient, and that, during the
evaporation, the mutual action between it and muriate of mag-
nesia, is favoured by the concentration, whence portions of
both are decomposed, and corresponding quantities of sulphate
of magnesia and muriate of sodaare formed. Nor is there any
thing connected with the mere results themselves, which proves
which of these views is just.

If the appeal be made to experiment, it is sufficiently esta-
blished, that sulphate of magnesia may be formed by the action
of sulphate of soda on muriate of magnesia. When these two
salts are boiled together in solution, a double decomposition
takes place at least partially, and portions of sulphate of mag-
nesia and muriate of soda are formed. On the other hand, the
reverse combinations may also, according to circumstances, be
established. We have seen reason to conclude, that they are
so from the agency of alcohol; and even in an aqueous solu-
tion, when certain proportions of the salts are used, they ap-
pear, under some circumstances, particularly that of a low tem-
perature, to take place toa certain extent. But still, these

q facts

el

PTO terete Se Ot

EAGER ERD GEOL ALS TE

OF SEA-WATER.. 229

facts only shew what decompositions may. occur from evapora-
tion or other processes ; they do not prove-what the actual
state of combination is in the original solution.

It is obvious, that: this is merely a case belonging to the

more general question, What is the state of combination in a
compound saline-solution, and on what principle can it be de-
termined what are the binary compounds that really exist in
it ?—a question of considerable importance, but one at the
same time of very difficult determination.
- When it is admitted that this. cannot be inferred with cer-
tainty from the actual products of analysis, the next most ob-
vious view is, that it may be inferred from a knowledge of the
real forces of affinity, as, according to these, certain binary
compounds must be formed; and as the state of the science
does not afford any certain estimate of the strength of attrac-.
tion, the problem, it may be concluded, is at present incapable
of being solved.

This conclusion, however, is: by no means certain. Attrac-
tion is so much modified in its operation by external forces,
and combinations are so frequently established from the in-.
fluence of these, that it is not clear that we should be able to
determine what combinations would exist in cases similar to.
those connected with the present investigation, from a know-
ledge of the degrees of attraction, were we even in possession
of it. It is rather, perhaps, from a knowledge of the influence

_ of these external forces, that an approximation to the solution

of the problem is to be attained ; and an extension of the prin-
ciple I have illustrated in the preceding part of this paper, it
appears to me may throw some light on the question.

If the foree of cohesion has so much power in modifying
chemical attraction, as to change its results, and establish com-

_binations independent of the relative degrees of strength with

which

230 ‘AN ANALYSIS

which it is exerted ; and if the reverse of cohesion, that is, the ;
power of a solvent, operates in establishing the reverse combi- |
-nations, as, in considering the agency of alcohol in this analysis,
there has appeared sufficient reason to conclude, then it will
follow, that, as in a concentrated medium, the least soluble
compounds are formed, so in a dilute medium, the more so-
luble compounds will be established. The power of the sol-
vent is exerted with greatest effect on those which are most
soluble ; and hence, if the reverse combinations even existed,
this power must change them, and establish the others, pre-
cisely as the power of cohesion acts with most energy on those
which are least soluble, and thus causes their formation, when
it is brought to act with sufficient force. Hence will follow
the simple rule by which the state of combination may be de-
termined; that, in any fluid containing the elements of com-
pound salts, the binary compounds existing in it will be those
which are most soluble in that fluid ; and the reverse combina-
tions will only be established by its concentration favouring
the influence of cohesion. Thus, if we concentrate a solution
containing sulphuric and muriatic acids, soda and lime, we
know, that from the influence of cohesion, the binary combi-
nations will be those of sulphuric acid with lime, and of muri-
atic acid with soda. And on the same principle, we may in-
fer, that in a dilute solution containing these elements, the
combinations will, from the influence of the power the reverse
of cohesion, that of the solvent action of the liquid, be those
of sulphuric acid with soda, and muriatic acid with lime. In
a concentrated solution, containing muriatic and sulphuric
acids, soda and magnesia, sulphate of magnesia and muriate of
soda are formed ; and, on the same principle, in a dilute solu-
tion, there must exist sulphate of soda and muriate of magne-
sia.

This

eS ees ae

OF SEA-WATER. 231

-» This principle, if just, is an. important one, as enabling us
to determine the state of binary combinations in a saline li-
quor. I add, therefore, one other illustration of the reasoning
on which it rests. ott
Suppose that in 2 compound saline solution, that is, one
containing more than one acid and one base, the acid and ‘the
base which have the strongest attraction, are those which aire
most soluble, or form the most soluble compound ; the solvent
power of the liquid operating at the same time, will concur
with this, and favour their combination ; and any other acid
and base likewise present, will of course, at: the same time,
combine. But suppose the more powerful attraction to belong

‘to those which form an insoluble compound, the solvent power

counteracts this, and prevents the combination. And the
more this power is increased, which is done by increasing the
quantity of the solvent, the more will this be counteracted.
‘The reverse combinations will therefore be established by the
operation of the opposite affinities. Hence, generally speak-
ing, in a dilute solution, the binary combinations must be
‘those which form the most soluble compounds, and very pow-
erful attractions would be required to counteract this.
Applying this principle to the composition of sea-water, or
rather to the question with regard to the sulphate of soda, and
sulphate of magnesia, it is obvious, that the former is to be
considered as the original ingredient, and the latter as a proe
duct of the evaporation ; for muriate of magnesia, and sulphate
of soda, are, on the whole, more soluble in water than muriate
of soda and sulphate of magnesia. On the same principle it
follows, still more unequivocally, that. the lime exists in the
state of muriate of lime, with a portion of sulphate of ‘soda
equivalent to the quantity of sulphate of lime which \the,eva-

7 poration affords. The salts, therefore, really existing in)sea-

water,

932 AN ANALYSIS

water, are muriate of soda, muriate of magnesia, muriate of
lime, and sulphate of soda. The quantity of muriate of soda
is less than what is obtained by evaporation, for a portion of it
is formed by the decompositions which occur; the quantity of
muriate of magnesia is larger, as a portion of it is decompo-
sed ; the quantity of muriate of lime is inferred from the quan-
tity of sulphate of lime ; and the quantity of sulphate of soda
is determined from the quantities of sulphate of magnesia and
sulphate of lime obtained. The proportions may thus be easily
assigned. Referring to the preceding analyses, the propor-
tions in a pint, according to this principle, will be the follow-

ing :

According to the first analysis,.

Muriate of Soda, - 170.2 grains.
Magnesia, 30.6
Lime, - 5.8
Sulphate of Soda, - 21.9
228.5 grains.

According to the second analysis :

Muriate of Soda, * 165.2
— Magnesia, 31.6
-—— Lime, - 5.9
Sulphate of Soda, - 24.9

227.6

If the opposite view be adopted, that the sulphate existing
in sea-water is not sulphate of soda, but sulphate of magnesia ;
then the ingredients and their proportions will be as follow :

According

OF SEA-WATER. 233

opunstinias to the first analysis,

Muriate of Soda, - 188.3 grains.
————— Magnesia, 16
-- Lime, 20 5.8
Sulphate of Magnesia, 18.4

228.5

According to the second analysis,

Muriate of Soda, = 185.6
-———— Magnesia, 15.2
Lime, - 5.9

Sulphate of Mog vce 20.9
221.6

But this view rests on no principle, and is, as I have stated,
less probable than the other *.
Vou. VIII. P. I. Gg The

to)

*There is sometimes obtained in the large way, from the products of the
evaporation of sea-water, a triple salt, which has not been noticed by che-
mists, but which appears to be of definite composition, and is distinguished
by peculiar properties,—a Sulphate of Magnesia and Soda. It is formed in pu-
rifying the sulphate of magnesia procured by the first evaporation from the
bittern of sea-salt. In this process the sulphate, which is impure, both from
the intermixture of muriate of soda and muriate of magnesia, and perhaps,
also, of ‘sulphate of soda, is dissolved in water, and by evaporation and cool-
ing is obtained crystallised ; a fresh quantity of it is added to the’ residual li-
quor, and by the necessary evaporation and cooling, a new crystallization is
produced ; this is repeated for a third or fourth time; and it is in these latter
erystallizations that this triple salt is formed, frequently in considerable quanti-
ty, and usually at a high temperature, being precipitated even m theboiler. It
erystallises in rhombs, at first irregular and semitransparent-; but by solution in
water, and a second crystallization, is obtained in more regular rhombs, trun-
cated on the acute angles, on the obtuse angles and edges, ‘and on the terminal

edges,

2384 AN ANALYSIS

The difficulties attending the perfect separation of com-
pound salts from each other, by crystallization, even with the
aid

edges, considering the rhomb as a four-sided prism, and transparent. The cry-
stals are permanent in the air; they are soluble in little more than three times
their weight of water, at the temperature of 60°; they do not undergo the
watery fusion from heat, but suffer decrepitation. In. these properties, this salt
differs entirely from sulphate of soda, or sulphate of magnesia.

To determine its composition, 20 grains reduced to powder were exposed
to heat, raised gradually nearly to redness ; they lost from the escape of water
5.6 grains. The residual powder was dissolved in water, and muriate of ba-
rytes was added as long as any precipitation was produced. The precipitate
dried at a red heat, weighed 23.9 grains, equivalent to sulphuric acid 8.2
grains. To the clear liquor carbonate of ammonia was added, which did not
impair the transparency ; phosphoric acid was then dropped in, which produ-
ced a copious precipitation. The precipitate, calcined at a red-heat, weighed
5.3 grains, equivalent to 2.1 of magnesia, or 6.4 of sulphate of magnesia ;
the residual liquor being evaporated to dryness, the dry mass was submitted
to heat, gradually raised, as long as any vapours exhaled ; it afforded, by solu-
tion in water and evaporation, muriate of soda in cubes, which, after expo-
sure to a red heat, weighed 6.4 grains, equivalent to 7.8 grains of sulphate of
soda. 100 grains of the salt, therefore, afford of

Sulphate of Magnesia, — 32 grains.
Soda, - 39
Water of Crystallization, - 28
Loss, - - 1
100

It afforded also a slight trace of muriatic acid; its solution being in a very
slight degree rendered turbid by nitrate of silver, probably owing to the inter-
mixture of a little muriate of soda, as an extraneous ingredient, ‘This ac-
counts for the proportion of sulphuric acid, as inferred from the quantities of
the bases, being a little larger than that directly obtained by the precipitation by
muriate of barytes.

The difference of crystalline form, as well as other differences of proper-
ties in the salt from those, either of sulphate of soda or sulphate of magnesia,
sufficiently prove that it is not merely an intermixture of the two, but that it
is of definite composition. It deserves to be remarked, too, that it has not
the same relation to water that either of these salts has, or any mean be-

tween

a

OF SEA-WATER, 235

aid of the action of alcohol, either as a solvent or a precipitant,
are so great, that analyses executed in this mode can scarcely
be perfectly accurate. And as it appears, if the preceding ob-
servations are just, that there is no certainty in the conclusion
that the products of analysis by evaporation or crystallization
are the real ingredients, no peculiar advantage in this respect
belongs to this method, and just as much information is ob-
tained by discovering the acids and bases which exist in solu-
tion, and then inferring, according to the most probable view,
what the states of binary combination are in which they exist.
This kind of analysis has the advantage, that it can be execu-
ted with much more precision than the other: it is liable to
fewer sources of error, and, by finding the quantities, not of
the compounds, but of the elements, any error that is introdu-
ced is discovered, when the binary compounds are inferred.
To ensure accuracy, therefore, it was desirable to apply it to
the illustration of the present subject, more especially as the
preceding analyses, though they do not differ greatly in the
results, still, from these difficulties, do not exactly corre-
spond.

Different methods might be employed. The following is

,the one I have preferred.

To a pint of sea-water, reduced by evaporation to nearly
one-fourth, at which state of concentration no crystallization
nor deposition takes place, muriate of barytes was added as
long as any precipitation occurred. By a preliminary trial, it

Gg 2 was

tween them; the quantity of its water of crystallization being considerably
less. Its taste is much less disagreeable than that of sulphate of soda or sulphate
of magnesia ; it might therefore probably be introduced with advantage as a pur-
gative salt, especially as it could be procured at a low price; and from its
composition, it would afford a very good substitute for the aperient mineral
waters, which usually owe their activity to sulphate of soda and sulphate of
magnesia.

236 AN ANALYSIS

was found that the precipitate gives no effervescence with mu-
riatic acid, nor suffers any change. It was therefore sulphate
of barytes. Dried by a low red heat, it weighed 43 grains,
equivalent to 14.4 sulphuric acid.

By this step the whole salts in the sea-water were convert-
ed into muriates. It remained to discover and estimate the
quantities of their bases.

To the clear liquor, oxalate of ammonia was added as long
as any turbid appearance was produced. ‘The precipitate,
washed and dried, by a heat of 150° continued for two hours,
weighed 8.5 grains. Calcined with a low red-heat, it gave of
carbonate of lime 5.2 grains. This, dissolved with strong ef-
fervescence in dilute muriatic acid, and the product being
heated with sulphuric acid, gave sulphate of lime, which, af-
ter exposure to a red-heat, weighed 7 grains, equivalent to 2.9
of pure lime. ;

To the clear liquor warmed, carbonate of ammonia was add-
ed, and phosphoric acid was dropped in * ; an abundant preci-
pitation took place of phosphate of magnesia and ammonia,
and additional portions of the phosphoric acid, with such addi-
tions of the carbonate as were necessary to preserve an excess
of ammonia in the liquor, were added, as long as any precipi-
tation was produced. The precipitate was converted, by cal-
cination for an hour at a red-heat, into phosphate of mag-
nesia. This weighed 37 grains, equivalent to 14.8 grains
of magnesia.

The clear liquor was evaporated to dryness, and the dry
mass was exposed to a heat gradually raised to redness, to ex-
pel the muriate of ammonia formed in the preceding opera-

tions.
® J shall have to state in a subsequent paper, the peculiar advantages attend-
ing this method of estimating the magnesia,

OF SEA-WATER. 937:

tions. Muriate of soda remained, which weighed 180.5 grains,
equivalent to 96.3 of soda, and 84.2 of muriatic acid.

‘This gives the quantity of Soda contained in the sea-water ;:
but it does not necessarily give the quantity of muriatic acid ;.
for if more of this acid be present than what the soda can neu-.
tralize, combined with portions of any of the other bases, (and
from the former ‘analysis this appears to be the case,) this.
quantity will be combined with ammonia in the preceding.
steps of the analysis, and is of course dissipated in the state of
muriate of ammonia.

This will appear, and the quantity be discovered by ascer-
taining what proportion of these bases the quantity of sulphu-
ric acid obtained by the analysis is capable of neutralizing,
thus finding if any excess of them remain ; and, from the quan-
tity of this, discovering the quantity of muriatic acid, which
would be requisite for saturation, which of course is the
quantity lost. 2.9 of lime, the quantity of this earth obtained
by the analysis, neutralize 4.1 of sulphuric acid; this deduc-
ted from 14.4, the quantity obtained, leaves 10.3, to neutralize
which, 5.1 of magnesia are required ; this deducted from 14.8,
the quantity of magnesia, leaves 9.7 of that earth ; to neutra-
lize this, 13.5, of muriatic acid are required ;. and this added to
the 84.2 in the muriate of soda, gives 97.7 grains as the total
quantity of Muriatic Acid.

The elements, then, of the salts, in a pint of pate are, .
by this sd oem

Lime, - 2.9 grains.
Magnesia, - 14.8
Soda, — -: 96.3
Sulphuric Acid, 14.4:
Mauriatic Acid, 97.7.

226.1 grains.
The

238 AN ANALYSIS

The proportions of the compound salts may be assigned from
these, according to whatever view may appear most probable,
of the state of combination in which they exist in sea-water,
and thus the results may be compared with those of the former
analyses.

Thus, supposing the elements to be combined in the modes
in which they are obtained by evaporation, that is, as muriate
of soda, muriate of magnesia, sulphate of magnesia, and sul-
phate of lime; the proportions of these salts in a pint, will
be

Muriate of Soda, - 180.5 grains.
—- Magnesia, - 23
Sulphate of Magnesia, - 15.5
- Lime, - 7.1
226.1

Supposing that the lime exists as muriate of lime, (which is
the most probable conclusion with regard to it), and farther
supposing, that the sulphuric acid exists in the state of sul-
phate of magnesia, the proportions will be

Muriate of Soda, - 180.5 grains.
- — Magnesia, - 18.3
— Lime, - 5.%
Sulphate of Magnesia, - 21.6

226.1 grains.

Or, lastly, supposing that the sulphuric acid exists in the
state of sulphate of soda, the proportions will be

Muriate

OF SEA-WATER. 239:

Muriate of Soda, - 159.8 grains.
———— Magnesia, - 35.5
———_— Lime, _- BE
Sulphate of Soda, - 25.6

eee

226.1 grains..

These proportions differ somewhat, though not very mate-—
rially, from those found by the other modes of analysis. The
principal differences consist in the quantity of magnesia, and
of sulphuric acid being rather larger. This is evidently to be
ascribed to the modes of detecting sulphuric acid by barytes,
and magnesia by phosphoric acid and ammonia, being so per-
fect, that the entire quantities of them are found; while, in
the other modes, from the difficulty of effecting the entire se-
paration of salts from each other, a small portion of. sulphate
of magnesia, or of muriate of magnesia and sulphate of soda,
had remained with the muriate of soda, and though subcarbo-
nate of soda was employed to decompose them, aie decompo-
sition is not altogether perfect. -In the mode of analysis, too,
by re-agents, the presence of water in the products can be
more completely excluded, and to this, probably, is to be a-
scribed the absolute quantity of saline matter being a little less

‘ according to this analysis, than it is in the others *.

Of

* In another analysis of sea-water, in which subcarbonate of ammonia was
employed to precipitate the magnesia, a solution of it being added to the water
concentrated by evaporation, the clear liquor, after the subsidence of the preci-
pitate being evaporated to dryness, the saline matter being exposed to heat, to
dissipate the muriate of ammonia ; being re-dissolved in water, the subcarbonate
of ammonia again added, and this repeated for a third, and eyen a fourth time,

the results gave the following proportions of the elements,
Lime,

240 AN ANALYSIS

Of the different views which may be taken of the state of
combination of the elements, I have already inferred, that the
one which supposes the sulphuric acid to exist in the state of
sulphate of soda, is the most probable ; and as the mode of
analysis by re-agents is the most accurate, the last table may
be considered as that. which exhibits the nighest approxima-
tion to the real composition of sea-water, both with regard to
its ingredients, and their proportions.

I had proposed to add a few observations on the analysis
of salt brines ; but as they are merely applications of the prin-
ciples already illustrated, it is sufficient to state them briefly,
or to notice those which present rather striking results.

Krarrotu has given a laborious investigation of the nature
of these brines ; in the greater number of them, he states as in-
gredients, muriate of soda, muriate of magnesia, muriate of
lime, and sulphate of lime. It is obvious, that there are no
just grounds whence this composition can be inferred ; it is
much more probable, that sulphate of soda is the ingredient,

and.
Lime - - 2:9 grains.
Magnesia, - - 13.
Soda, - - 97.6
Sulphuric Acid, - 15.2 ;
Muriatie Acid, - 96.9

225.6 grains.

The principal difference here, is the proportion of magnesia being somewhat
smaller, evidently owing to its precipitation by the carbonate of ammonia, even
with the aid of the methods employed to promote it, being imperfect.

ay

x
;

OF SEA-WATER. 241

and that, acting on a portion bf the muriate of lime, it forms
sulphate of ie.

In other analyses, in those, for Basile of the salt brines
of Lorraine, by Nicuoas *, muriate of soda, sulphate of soda,
sulphate of lime, muriate of magnesia, and muriate of lime, are
enumerated as ingredients: Here it is still more evident, that
there is no proof of the previous existence of sulphate of lime;
on the contrary, as both muriate of lime and sulphate of soda
are present, they must, in the concentration of the liquor by
evaporation, form by their mutual action muriate of soda and
sulphate of lime; and the quantity therefore of this sulphate
which may be obtained, must have this origin.

In general, when muriate of lime and muriate of magnesia
are stated as ingredients with sulphate of lime, no sulphate of
soda or sulphate of magnesia is found. The reason is obvious,
that if either of these salts existed, it would re-act on the mu-
riate of lime, and form sulphate of lime. But when muriate
of lime is not found, sulphate of magnesia, or sulphate of soda,
is often stated as an ingredient, obviously owing to the circum-
stance, that although a portion of muriate of lime has been
present, so as to form sulphate of lime, there has not been a
quantity sufficient to decompose the whole sulphate of soda, or
sulphate of magnesia.

A striking example of these facts is to be found in Dr Hen-
RY’S eet mice of the different varieties of sea and rock salt +.
In four varieties of rock-salt, there were found small quanti-
ties of muriates of lime and magnesia, with a portion of sul-
phate of lime, but no sulphate of magnesia; while in the dif-
ferent varieties of sea-salt, British and foreign, there was ne
appreciable quantity, and in some of them no trace whatever

Vor. VU P.L Hh of

* Annales de Chimie, t. 20.
Philosophical Transaetions, 1810.

242 AN ANALYSIS

of muriate of lime, but in all of them with sulphate of lime
considerable quantities of sulphate of magnesia. In the latter,
therefore, the muriate of lime had been converted entirely into
sulphate of lime from the excess of sulphate of magnesia ; in
the former, from the deficiency of the sulphate, a portion of
the muriate of lime had remained undecomposed.

A result somewhat similar, and which affords a very direct
application of the same principles, is stated by Mr Horner, in
his analysis of the salt-brine at Droitwich, compared with that
of Cheshire *. The latter contains a little muriate of lime ;
the former contains none. But, then, that of Droitwich con-
tains sulphate of soda and sulphate of lime ; there is every pro-
bability, therefore, that its muriate of lime has been converted
into sulphate of lime by the sulphate of soda, which is in ex-
cess; while in the Cheshire brine, as there is no sulphate of
soda in excess, that is, none after the evaporation, a portion of
muriate of lime remains.

There is a singular fact stated by Dr Henry with regard to
what is called fishery salt, prepared from salt brine, which
seems to admit of explanation only on these views. He found
the proportion of sulphate of lime mixed with it to be less, as it
was collected at a later period of the evaporation ; that drawn
from the boiler, after two hours application of the heat, con-
tained in 100 parts 16 of sulphate of lime ; that, after 4 hours,
contained only 11; and that, after 6 hours, only 33. Now if
the water of this brine held sulphate of lime in solution, the
sulphate would begin to be deposited when the quantity of
water was diminished to that extent that it was unable to re-
tain the whole dissolved ; and, in the progress of the evapora-
tion, would continue to be deposited proportional to this,

' to

* Geological Transactions, vol. it.
S >

ke et oe

OY SEA-WATER. 243

to the end of it, and the muriate of soda would be depo-
sited in the same manner ; so that the proportion between the
two would continue nearly the same, But if the sulphate of
lime did not exist in solution, but derives its origin from the
action of sulphate of soda on muriate of lime, which these
brines contain, this action would take place, when a certain
degree of concentration of the liquor had been attained; the
sulphate of lime would then be copiously deposited ; but as
the evaporation continued to proceed, its quantity would be di-
minished, as the quantity either of sulphate of soda, or of mu-
riate of lime, became less; and its deposition would cease
when either of these salts was exhausted.

This is placed in a still clearer light, by an analysis of these
brines, after evaporation, to a certain extent, compared with
their original composition. A brine from Northwich was
found by Dr Henry to afford, by evaporation, saline matter,
which, he inferred, contained in 1000 parts, muriate of lime
and muriate of magnesia in nearly equal proportions 5 parts,
sulphate of lime 19 parts, muriate of soda 974 parts. But the
brine remaining after the separation of all the common salt,
which it is thought worth while to extract, afforded saline mat-
ter by evaporation, which he found to contain, in 1000 parts,
muriate of magnesia 35, muriate of lime 32, sulphate of lime 6,
muriate of soda 927. Here, in the progress of the evapora-
tion, the quantity of sulphate of soda, which may be consider-
ed as an original ingredient of the brine, had been diminished
by the decomposition arising from its action on the muriate of
lime. The liquor, therefore, after this, afforded by farther
evaporation, along with a large quantity of muriate of lime, a

small quantity only of sulphate of lime ; while, if this sulphate

had been an original ingredient, it would have continued to be
afforded at least in equal proportion.
Hh 2 Something

244 AN ANALYsI8, &c.

Something similar to this occurs in the evaporation of sea-
water. It is, after a certain extent of evaporation, but while a
large portion of liquor still remains, that the precipitation of
sulphate of lime takes place ; that is, after the concentration is
sufficient to favour the mutual action of the sulphate of soda,
or sulphate of magnesia, and muriate of lime. After this, the
quantity diminishes as the evaporation proceeds, till at last not
a trace of it, or of sulphate of lime, remains in the bittern,
which consists of muriate of soda, muriate of magnesia, and
sulphate of magnesia alone. This curious fact has not been
particularly noticed, though it is in consequence of it that mag-
nesia is prepared from bittern on the large scale, perfectly
pure.

All these facts seem scarcely to admit of any explanation,
but on the view that has been stated, and they afford a strong
confirmation of it.

XI.

“

a ET el

XII. Elementary Demonstration of the Composition of Pres-
sures. By Tuomas Jackson, LL.D. F.R.S. Eni.
and Professor of Natural Philosophy in the Universi--
ty of St. Andrew’s.

(Read June 3, 1816.)

T is well-known as a fundamental principle in statics, that’
“« Two pressures, represented in direction and quantity by

“ two adjoining sides of a parallelogram, are equivalent to one
“ represented in direction and quantity by the diagonal
“ which passes through the point at which these sides meet.”
A demonstration of this proposition, that shall be at once suf-
ficiently concise, and sufficiently elementary, to admit of its be-
ing with propriety introduced into a course of academical in-.
struction, has been hitherto, so far as I know, a desideratum..
The following may perhaps be — to possess that advan-.
tage.. :

Lema.
“ If the equivalent of two pressures, represented by the ad-
“ joining sides of a rectangle, given in species, be always re-
“« presented in direction by the eee gee diagonal, it's shall
“ be represented by the same in quantity.”
Let

246 FLEMENTARY DEMONSTRATION OF THE

Let ABCD be a rec- FIG.1
tangle, and AC the dia-

gonal passing through eo
A; draw EAF perpen- ”
A
dicular to AC, and let
fall the perpendiculars — fort
BF, BH, DG, DE: then x
shall ABCD, AFBHand =» c
AEDG be similar rectangles ; and if, in each of these, the
equivalent of the pressures represented in direction and quan-
tity by the sides, be represented in direction by the diagonal,
it shall be represented by the same in quantity also. For if
the forces AH and AF be equivalent to m AB; AE and AG
shall be equivalent to m AD; and AB and AD to m AC; or
m AB and mAD to m AC: that is, the forces AH, AF, AE,
and AG, will be equivalent to m AC: But AE and AF are
equal and opposite : hence the forces AH and AG are equi-

valent to m= AC. But AH and AG are equivalent to AC;
therefore m = 1.

1. Now let ABDC be any square ; and let the sides AB and
CD be produced indefinitely towards B and D; draw the dia-
gonal AD; in CD produced, take DF equal to AD ; join AF;
take FH equal to AF; join AH, and so on.
the rectangles ACFE, ACHG, &c.

It is obvious, that AD, AF, AH, &c. bisect the angles
BAC, BAD, BAF, &c. respectively. Hence the resultant of

AB

And complete

aio

i ee

_AC makes with AB an angle:

COMPOSITION OF PRESSURES- Q4AT

AB and AC, which are equal, must be represented in direc-
tion by AD; and therefore by the same in quantity also. The
equivalent Bo AE and AC being the same with that of BE and
AD, which are equal, will be represented in direction, and
therefore in quantity by AF, (vid. Lemma). Thus may the-
proposition be proved of any rectangle whose diagonal makes,
with one of the sides any angle found by the continued bisec-.
tion of a right angle.

2. Let (@) be any angle in the series above mentioned ; a
proposition shall be true in relation to any rectangle whose
diagonal forms with one of the sides an angle that is any mul--
tiple of (a). .

Let AB and BC be two sides FIG.3
of a rectangle whose diagonal:

in relation to which the propo--
sition has been already pro-
ved ; and let CAG be equal to.
(a); the proposition shall be.
true in relation to the angle-
BAG;; for let GED be parallel ™

to AC, and draw the perpendiculars AD, EF, GH:. Ie is al-
ready proved, that two forces represented by AD and AF are
equivalent to the single force represented by AE; for
< DAE= < BAC. AE may therefore be resolved into AD
and AF; that is, the forces AK and AC are equivalent to the
forces AD and AH, or to the single force AG. Since, then, |
AB and BC are equivalent to AC ; and.AC and CG equiva-
lent to AG ; AB and BG must be equivalent to AG.

3. Let.

248 ELEMENTARY. DEMONSTRATION, &c.

3. Let BAD be an angle in-
commensurable with a right +.
angle. The proposition is true
in relation to BAC, the multiple
of (a) next less than BAD, and
of BAE, the multiple of (a) next ™
higher, the difference between
which (= a) may be less than any «=
assigned angle. But the equivalent of AB and BD must, in
respect of direction, be always intermediate between the equi-
valent of AB, BC, and that of AB, BE. It must, therefore,
pass through D; and this is evidently true in the case of any
similar rectangle ; that is, so long as the angle BAD remains
the same. Hence it must be represented by AD, also in quan-
tity (vid. Lemma).

From what is said above in § 2. it is manifest that celia has
now been proved universally of the rectangle, may be extend-
ed to the oblique-angled parallelogram.

XIII.

XIII. Account of the remarkable Case of Marcarer Lyart, who
continued in a State of Sleep nearly Six Weeks. By the
Reverend James Brewster, Minister of Craig. Com-

municated by Dr Brewster.

(Read February 19. 1816. )

My Dear Broruer, Manse of Craig, Feb. 16. 1816.

HE inclosed account was drawn up at the request of Roser
Grane, Esq. when all the circumstances were fresh in my

own recollection, and that of all with whom I had occasion to
confer on the subject. Since you requested me to send you a
correct copy of the whole case,I have renewed my inquiries a-
mong the friends of the young woman, and submitted my ac-
count to several persons, who were most capable of supplying
any omissions, or correcting any mistakes. [ can confidently
vouch for the general accuracy of the statement ; but would not
wish its credibility to rest entirely on my single testimony. I
have, therefore, procured the signature of the young woman’s fa-
ther, and of several gentlemen, with whom you are more or less
- acquainted, and who frequently saw hér during her illness. The
account of her recovery, on the 8th of August, indeed, rests
wholly on the testimony of the father, which there is not the
smallest reason to doubt. I am sensible, that many of the cir-

cumstances which I have mentioned, may appear to be unne-

Vou. VII. P. 1. Ti cessarily

250 ACCOUNT OF MARGARET LYALL, WHO CONTINUED

eessarily minute, or even altogether unimportant ; but, in de-
tailing so remarkable a case, I did not think myself qualified or
entitled to select according to my own judgment ; and consi-
dered it to be my business, as a reporter, merely to relate, as
clearly and correctly as possible, whatever was observable in the
situation of the patient. I have noted, also, her previous em-
ployment, the places where she resided, and some of the indi-
viduals who attended to her case, partly to render the account
more intelligible, and partly to enable others to make farther
inquiries for themselves. I may mention farther, in case you
may not be aware of the circumstance, that there is a similar
case recorded in the T'ransactions of the Royal Society of Lon-
don for 1705, vol. xxiv. p. 2177.
Yours, &c.
To Dr Brewster. Jas. Brewster.

Margaret Lyatt, a young woman, about twenty-one years
of age, daughter of Joun Lyat1, shoemaker in the parish of
Marytown, served during the winter half-year preceding
Whitsunday 1815, in the family of Perrr Arxiry, Esq. of
Dunninald, in the parish of Craig. At the last mentioned
term, she went as servant to the Reverend Mr Foorr of Lo-
gie; but, in a few days after entering her place, was seized with
a slow fever, which confined her to bed rather more than a
fortnight. During the latter part of her illness, she was convey-
ed to her father’s house; and, on the 23d of June, about eight
days after she had been able to leave her bed, she resumed her
situation with Mrs Foorr, who had, in the mean time, removed
to Budden, in the parish of Craig, for the benefit of sea-bath-
ing. She was observed, after her return, to do her work rather
in a hurried manner; and, when sent upon any errand, to run

or

an

IN A STATE OF SLEEP NEARLY SIX WEEKS. 251

or walk very quickly, as if impatient to finish whatever she
had in hand. Her health, however, appeared to be perfectly
restored, except that her menses were obstructed. On Tuesday
morning, June 27th, about four days after her return to service,
she was found in bed in a deep sleep, with the appearance of blood
having flowed from her nose ; and about half a Scotch pint of
blood was perceived on the floor, at her bed-side. All attempts
to awaken her were utterly ineffectual ; and she was conveyed in
a cart to her father’s house, about half a mile distant from Bud-
den. Dr Grzson, physician in Montrose, having been called,
a pound of blood was taken from her arm; but she still remain-
ed in the same lethargic state, without making the slightest
motion, or taking any nourishment, or having any kind of eva-
cuation, till the afternoon of Friday the 30th day of June,
when she awoke of her own accord, and asked for food. At
this period she possessed all her mental and bodily faculties ;
mentioned distinctly, that she recollected her having been awa-
kened on Tuesday morning at two o'clock, by a bleeding at her
nose, which flowed very rapidly ; said, that she held her head
over the bed-side till the bleeding stopped ; but declared, that,
from that moment, she had no feeling or remembrance of any
thing, and felt only as if she had taken a very long sleep. An
injection was administered with good effect, and she went to
sleep as usual; but, next morning, (Saturday, July 1.), she was
found in the same state of profound sleep as before. Her
breathing was so gentle as to be scarcely perceptible ; her coun-
tenance remarkably placid, and free from any expression of
distress ; but her jaws were so firmly locked, that no kind of
food or liquid could be introduced into her mouth. In this si-
tuation she continued for the space of seven days, without any
motion, food, or evacuation either of urine or feces. At the
end of seven days she began to move her left hand; and, by

1i2 pointing

252 ACCOUNT OF MARGARET LYALL, WHO CONTINUED

pointing it to her mouth, signified a wish for food. She took
readily whatever was given to her, and shewed an inclination
to eat more than was thought advisable by the medical atten-
dants. Still, however, she discovered no symptoms of hearing,
and made no other kind of bodily movement, than that of her
left hand. Her right hand and arm, particularly, appeared
completely dead and devoid of feeling, and, even when pricked
with a pin, so as to draw blood, never shrunk in the smallest
degree, or indicated the slightest sense of pain. At the same
time, she instantly drew back the left arm, whenever it was
touched by the point of the pin. She continued to take food,
whenever it was offered to her; and when the bread was put
into her left hand, and the hand raised by another person to
her mouth, she immediately began to eat slowly, but unremit-
tingly, munching like a rabbit, till it was finished. It was re-
marked, that, if it happened to be a slice of loaf which she was
eating, she turned the crust, when she came to it, so as to intro-
duce it more easily into her mouth, as if she had been fully sen-
sible of what she was doing. But when she had ceasedto eat,
her hand dropped upon her chin or under lip, and rested there,
till it was replaced by her side, or upon her breast. She took
medicine, when it was administered, as readily as food, without
any indication of disgust ; and, in this way, by means of castor
oil and aloetic pills, her bowels were kept open ; but no evacua-
tion ever took place without the use of a laxative. It was ob-
served, that she always gave a signal, by pushing down the
bed-clothes, when she had occasion to make any evacuation.
The eye-lids were uniformly shut, and, when forced open, the
ball of the eye appeared turned upwards, so as to shew only
the white part of it. Her friends shewed considerable reluc-
tance to allow any medical means to be used) tor her recovery;
but, about the middle of July, her head was shaved, and a:large

blister

ne

_IN A’STATE OF SLEEP NEARLY SIX WEEKS. 253

blister applied, which remained nineteen hours, and produced
an abundant issue, yet without exciting the smallest symptom
of uneasiness in the patient. Sinapisms were also applied ta
her feet, and her legs were moved from hot water into cold,
and vice versd, without any appearance of sensation. In this
state she remained, without any apparent alteration, till Tues-
day the 8th day of: August, precisely six weeks from the time
when she was. first seized with her lethargy, and without ever
appearing to be awake, except, as mentioned, on the afternoon of
Friday the 30th of June. During the whole of this period, her
colour was generally that of health ; but her complexion rather
more delicate than. usual, and occasionally changing, sometimes
to paleness, and at other times to a feverish flush.. The heat
of her body was natural ; but, when lifted out of bed, she ge-
nerally became remarkably cold. The state of her pulse was
not regularly marked ; but, during the first two weeks, it was
generally at 50; during the third and fourth week, about 60;
and, on the day before her recovery, at 70 or 72; whether its
increase was gradual was not ascertained. She continued, du-
ring the whole period, to breathe in the same soft and almost
imperceptible manner as at first; but was observed occasional-
ly, during the night time, to draw her breath more strongly,
like a person who had fallen asleep. She discovered no symp-

toms of hearing, till about four days before her recovery, when,

upon being requested, (as she had often been before, without
effect), to give a sign if she heard what was said to her, she
made a slight motion with her left. hand, but soon ceased again.
to shew any sense of hearing. On Tuesday forenoon, the day
of her recovery, she shewed evident signs of hearing ; and by
moving her lett hand, intimated her assent or dissent in a to-
lerably intelligent manner ; yet, in the afternoon of the same

day, she seemed to have again entirely lost all sense of hear-
ing.

254 ACCOUNT OF MARGARET LYALL, WHO CONTINUED

ing. About eight o’clock on Tuesday evening, her father, a
shrewd intelligent man, and of a most respectable character,
anxious to avail himself of her recovered sense of hearing, and
hoping to rouse her faculties by alarming her fears *, sat down
at her bed-side, and told her that he had now given consent, (as
was in fact the case,) that she should be removed to the Mon-
trose Infirmary; that, as her case was remarkable, the Doctors
would naturally try every kind of experiment for her recove-
ty; that he was very much distressed, by being obliged to put
her entirely into their hands ; and would “ fain hope,” that this
measure might still be rendered unnecessary, by her getting
better before the time fixed for her removal. She gave evident
signs of hearing him, and assented to his proposal of having
the usual family-worship in her bed-room. After this was
over, she was lifted into a chair till her bed should be made;
and her father, taking hold of her right hand, urged her
to make an exertion to move it. She began to move first the
thumb, then the rest of the fingers in succession, and next her
toes in like manner. He then opened her eye-lids ; and, pre
senting a candle, desired her to look at it, and asked, whether
she saw it. She answered, “ Yes,” in a low and feeble voice.
She now proceeded gradually, and in a very few minutes, to
regain all her faculties; but was so weak as scarcely to be able
to move. Upon being interrogated respecting her extraordi-

nary

* Lest it might be supposed, that this procedure of the father implied a sus-
picion on his part of some deception being practised by the young woman, it may
be proper to state, that it was suggested by his own experience in the case of
another daughter, who had been affected many years before in a very extraordi-
nary degree, with St Virus’s dance, or, as it is termed in this country, “* The
<: Jouping ague ;” and who was almost instantaneously cured by the application

of terror.

IN A STATE OF SLEEP NEARLY SIX WEEKS. 255

nary state, she mentioned, that she had no knowledge of any
thing that had happened ; that she remembered, indeed, ha-
ving conversed with her friends at her former-awakening, (Fri-
day afternoon 30th of June), but felt it a great exertion then
to speak to them; that she recollected also having heard. the
voice of Mr Cowrr, Minister in Montrose, (the person who.
spoke to her on the forenoon of Tuesday the 8th of August,)
but did not hear the persons who spoke to her on the after-
noon of the same day; that she had never been conscious of
having either needed or received food, of having been lifted to
make evacuations, or of any other circumstance in her case.
She had no idea of her having been blistered ; and expressed
great surprise, upon discovering that her head was shaved. She
continued in a very feeble state for a few days, but took her
food nearly as usual, and improved in strength so rapidly, that
on the last day of August she began to work as a reaper in the
service of Mr Arxuiey of Dunninald; and continued to per-
form the regular labour of the harvest for three weeks, without
any inconvenience; Extept being extremely — the —
day.
After the conclusion of the harvest, she went into Mr Anx-
LEY’S family, as a servant; and on. the 27th day of September,
was found in the morning, by her fellow-servants, in’ her for-
mer state of profound sleep, from which they were ‘inable' to
rouse her. She was conveyed immediately to her father’s
‘house, (little more than a quarter of a mile distant,) and re-
mained exactly fifty hours in a gentle, but deep sleep, without
making any kind of evacuation, or taking any kind of nourish-
ment. Upon awakening, she arose apparently in perfect.
health, took her breakfast, and resumed her work as usual at
Dunninald. On the 11th of October, she’was again found in

the

256 ACCOUNT OF MARGARET LYALL, WHO CONTINUED

the morning in the same lethargic state ; was removed to the
house of her father, where she awoke, as before, after the same
period of fifty hours sleep ; and returned to her service, with-
out seeming to have experienced any inconvenience. At both
of these times her menses were obstructed. Dr HENpErson,
physician in Dundee, who happened to be on a visit to his
friends at Dunninald, prescribed some medicines suited to that
complaint ; and she has ever since been in good health, and
able to continue in service *.

(Signed) Jas. Brewster,
Minister of Craig.

* On the morning of September 21. 1816, Marcarer Lyatz, whose case is
described above, was found in an out-house at Dunninald, hanged by her own
hands. No cause could be assigned for this unhappy act. Her health had been
good since the month of October 1815; and she had been comfortable in her
situation. It was thought by the family, that, a day or two preceding her
death, her eyes had the appearance of rolling rather wildly ; but she had assist-
ed the day before in serving the table, and Fossa in good spirits that evening.
On the following morning, she was seen to bring in the milk as usual, and
was heard to say in passing rather hurriedly through a room, where the other
maids were at work, that something had gone wrong about her dairy; but
was not seen again till she was found dead about half an hour after. She is
known to have had a strong abhorrence of the idea of her former distress re-
curring ; and to have occasionally manifested, especially before her first long
sleep, the greatest depression of spirits, and even disgust of life.

a

IN A STATE OF SLEEP NEARLY SIX WEEKS. 257

I hereby certify the preceding account of my daughter Mar--
GArEt’s illness and recovery to be correct in every circum-.
stance, according to the best of my recollection.

(Signed) Joun Lyat.

> We hereby attest, That the above-mentioned particulars in
the extraordinary case of Marcarer Lyatt, are either consist-
ent with our personal knowledge, or agreeable to all that we
- have heard from the most credible testimony.
(Signed) Perer Arxiey of Dunninald.
Anow. Frrcusson, Minister of Maryton. .
Wii. Gisson, Physician in Montrose.

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XIV. A General Formula for the Analysis of Mineral Waters. :
By Joun Murray, M.D. F.B.S. E.

(Read June 7. 1816. )

HE analysis of Mineral Waters has always been consider-
- edas a difficult operation. Numerous methods are em-.
ployed to discover their ingredients, and estimate their quan-
tities, many of which are liable to errors. This diversity of
method itself is a source of discordant results. And to those
not familiar with such researches, it presents the difficulty of-
ten of determining what process is best adapted to discover a
particular composition. Hence the advantage of a general for-
mula, if this could be given, applicable to the analysis of all
waters. The views which have been stated in the papers,
connected with this subject, which I have had the honour of
submitting to the Society, have suggested a method which ap-
pears to me to admit of very general application, and to be-
simple, not difficult of execution, nor liable to any sources of
error but what may be easily obviated. The principles on
which this method is founded, and the details of the process
itself, form the subject of the following observations.
Two methods of analysis have been employed for discover-
ing the composition of mineral waters,—what may be called

Kk 2 the

260 A GENERAL FORMULA FOR THE

the direct method, in which, by evaporation, aided by the subse-
quent application of solvents, or sometimes by precipitants,
certain compound salts are obtained ; and what may be called
the indirect method, in which, by the use of re-agents, the prin-
ciples of these salts, that is, the acids and bases of which they
are formed are discovered, and their quantities estimated,
whence the particular salts, and their proportions, may be in-
ferred.

Chemists have always considered the former of these me-
thods as affording the most certain and essential information :
they have not neglected the latter; but they have usually em-
ployed it as subordinate to the other. ‘The salts procured by
evaporation, have been uniformly considered as the real ingre-
dients, and nothing more was required, therefore, it was ima-
gined for the accuracy of the analysis, than the obtaining them
pure, and estimating their quantities with precision. On the
contrary, in obtaining the elements merely, no information, it
was believed, was gained with regard to the real composition,
for it still remained to be determined, in what mode they were
combined, and this, it was supposed, could be inferred only
from the compounds actually obtained. This method, there-
fore, when employed with a view to estimate quantities, has

been had recourse to only to obviate particular difficulties at-
- tending the execution of the other, or to give greater accuracy
to the proportions, or, at farthest, when the composition is
very simple, consisting chiefly of one genus of salts.

Another circumstance contributed to lead to a preference of
the direct mode of analysis ;—the uncertainty attending the de-
termination of the proportions of the elements of compound
salts. This uncertainty was such, that even from the most ex-
act determination of the absolute quantities of the acids and
bases existing in a mineral water, it would have been difficult,

or

ANALYSIS OF MINERAL WATERS. 261

dr nearly impracticable, to assign the precise composition, and

the real proportions of the compound salts; and hence the

necessity of employing the direct method of obtaining them.

The present state of the science leads to other views.

If the conclusion were just, that the salts obtained by eva-
poration, or any analogous process from a mineral water, are
its real ingredients, no doubt could remain of the superiority
of the direct method of analysis ; and even of the absolute ne-
cessity of employing it. But no illustrations, I believe, are re-
quired to prove, that this conclusion is not necessarily true.
The concentration by the evaporation, must, in many cases,
change the state of combination, and the salts obtained are
hence frequently products of the operation, not original ingre-
dients. Whether they are so or not, and what the real com-
pesition is, are to be determined on other grounds than on
their being actually obtained; and no more information is
gained, therefore, with regard to that composition, by their be-
ing procured, than by their elements being discovered ; for
when these are known, and their quantities are determined,
we can, according to the principle from which the actual
modes of combination are inferred, whatever this may be, as-
sign with equal facility the quantities of the binary compounds
they form.

The accuracy with which the proportions of the constituent
principles of the greater number of the compound salts are now
determined, enables us also to do this with as much precision,
as by obtaining the compounds themselves. And if any error
should exist in the estimation of these proportions, the prose-
cution of these researches could not fail soon to discover it.

The mode of determining the composition of a mineral wa-
ter, by discovering the acids and bases which it contains, ad-
mits, in general, of greater facility of execution, and more ac-

curacy,

262 A GENERAL FORMULA FOR THE

curacy, than the mode of determining it by obtaining insulated
the compound salts. Nothing is more difficult than to effect
the entire separation of salts by crystallization, aided even by
the usual methods of the action of alcohol, either as a solvent
or a precipitant, or by the action of water as a solvent at dif-
ferent temperatures ; in many cases it cannot be completely
attained, and the analysis must be deficient in accuracy. No
such difficulty is attached to the other method. The princi-
ples being discovered, and their quantities estimated in gene-
ral from their precipitation in insoluble compounds, their en-
tire separation is easily effected. Nothing is easier, for ex-
ample, than to estimate the total quantity of sulphuric acid by
precipitation by barytes, or of lime by precipitation by oxalic
acid. And this method has one peculiar advantage with re-
gard to accuracy, that if any error is committed in the estima-
tion of any of the principles, it is discovered in the subsequent
step of inferring the binary combinations, since, if all the ele-
ments do not bear that due proportion to each other which is
necessary to produce the state of neutralization, the excess or
deficiency becomes apparent, and of course the error is detec-
ted. The indirect method, then, has every advantage over the
other, both in accuracy and facility of execution.

Another advantage is derived from these views, if they are
just, that of precluding the discussion of questions which other-
wise fall to be considered, and which must often be of difficult
determination, if they are even capable of being determined.
From the state of combination being liable to be influenced by
evaporation, or any other analytic operation by which the salts
existing in a mineral water are attempted to be procured, dis-
cordant results will often be obtained, according to the me-
thods employed ; the proportions at least will be different, and
sometimes even products will be found by one method which

are

ANALYSIS OF MINERAL WATERS. 263

are not by another. In a water which is of complicated com-
position, this will more peculiarly be the case. The Chelten-
ham waters, for example, have, in different analyses, afforded
results considerably different ; and, on the supposition of the
salts procured being the real ingredients, this diversity must
be ascribed to inaccuracy, and ample room for discussion, with
regard to this is introduced. In like manner, it has often
been a subject of controversy, whether sea-water contains sul-
phate of soda with sulphate of magnesia. All such discus-
sions, however, are superfluous. The salts procured are not
necessarily the real ingredients, but in part, at least, are pro-
ducts of the operation, liable, therefore, to be obtained or not,
or to be obtained in different proportions, according to the me-
thod employed. And all that can be done with precision, is
to estimate the elements, and then to exhibit their binary
combinations according to whatever may be the most probable
view of the real composition.

The process I have to state, conformable to these views, is
essentially the same as that which I employed in the analysis of
sea-water in a preceding memoir ; and it was the consideration
of the advantages belonging to it, that has led me to propose
it, with the necessary modifications, as one of general applica-
tion.

Mineral waters have been arranged under the four classes
of Carbonated, Sulphureous, Chalybeate, and Saline. But all of
them are either saline, or may be reduced under this division,
From waters of the first class, the carbonic acid which is in ex-
cess, is expelled by heat, and its quantity is estimated. Sul-
phuretted hydrogen is in like manner expelled or decomposed.
And iron may be detected by its particular tests, and removed
by appropriate methods. In all these cases the water remains,
with any saline impregnation which it has, and of course is es-

sentially

/

264 A GENERAL FORMULA FOR THE

sentially the same in the subsequent steps of its analysis as a
water purely saline; the precaution only being observed of
these principles being removed, and of no new ingredient be-
ing introduced by the methods employed.

The salts usually contained in mineral waters are Carbo-
nates, Sulphates, and Muriates, of Lime, of Magnesia and of
Soda. In proceeding to the analysis, a general knowledge is
of course first to be gained of the probable composition by the
application of the usual tests ; the presence of sulphuric and
carbonic acids being detected by nitrate of barytes, of muriatic
acid by nitrate of silver, of lime by oxalic acid, of magnesia
by lime-water or ammonia, and of any alkaline neutral salt by
evaporation. It will also be of advantage to obtain the pro-
ducts of evaporation, and ascertain their quantities, without
any minute attention to precision, the object being merely, by
these previous steps, to facilitate.the more accurate analy-
sis.

Supposing this to be done, and supposing the composition
of the water to be of the most complicated kind, that is, that
by the indications from tests, or by evaporation, it has afford-
ed carbonates, sulphates, and muriates of lime, magnesia and
soda, the following is the general process to be followed to as-
certain the ingredients, at their proportions.

Reduce the water by evaporation, as far as can be Mae
without occasioning any sensible precipitation or crystalliza-
tion ; this, by the concentration, rendering the operation of the
re-agents to be employed more certain and complete. Tt also
removes any free carbonic acid.

Add to the water thus concentrated a saturated solution: of
muriate of barytes, as long as any precipitation is produced,
taking care to avoid adding an excess. By a previous experiment,
let it be ascertained whether this precipitate effervesces:or not

with

a al all

>. eye

ener a

Miese iA

ANALYSIS OF MINERAL WATERS. 265

with diluted muriatic acid, and whether it is entirely dissolved.
If it is, the precipitate is of course carbonate of barytes, the
weight of which, when it is dried, gives the quantity of carbo-
nic acid ; 100 grains containing 22 of acid. If it do not ef
fervesce, it is sulphate of barytes, the weight of which, in like
manner, gives the quantity of sulphuric acid ; 100 grains, dried
at a low red-heat, containing 34 of acid. If it effervesce, and
is partially dissolved, it consists both of carbonate and sul-
phate. To ascertain the proportions of these, let the precipi-
tate be dried at a heat a little inferior to redness, and weigh-
ed; then submit it to the action of dilute muriatic acid ; after
this wash it with water, and dry it by a similar heat, its weight
will give the quantity of sulphate, and the loss of weight, that
of carbonate of barytes.

By this operation the carbonic and sulphuric acids are en-
tirely removed, and the whole salts in the water are converted
into muriates. It remains, therefore, first to discover and esti-
mate the quantities of the bases present, and then, to complete
the analysis, to find the quantity of muriatic acid originally
contained.

Add to the clear liquor a saturated solution of oxalate of
ammonia as long as any turbid appearance is produced. The
lime will be thrown down in the state of oxalate. The preci-
pitate being washed, may be dried, but as it cannot be expo-
sed to a red-heat without decomposition, it can scarcely be
brought to any uniform state of dryness with sufficient accura-
cy to admit of the quantity of lime being estimated from its
weight. It is therefore to be calcined with a low red-heat, by
which it is ‘converted into carbonate of lime, 100 grains of
which are equivalent to 56 of lime. But as a portion of car-
bonic acid may be expelled, if the heat is raised too high, or a
little water retained if it is not high enough; it is proper to

Vou. VIIL P. I. pot el convert

266 A GENERAL FORMULA FOR THE

convert it into sulphate, by adding sulphuric acid to a slight
excess, and then exposing to a full red-heat. ‘ihe dry sul-
phate of lime will remain, 100 grains of which contain 41.5 of
lime *. red et

The next step is to precipitate the magnesia. With regard
to this there is some difficulty, particularly as connected with
the design of the present formula. The principle on which it
is founded is, first, to remove all the acids but the muriatic,
and, secondly, to remove the bases, or otherwise estimate their
quantities. The lime and the magnesia may be removed by
precipitation ; the soda cannot. ‘The process, therefore, must
be so conducted, as to leave it at the end in the state of mu-
riate of soda. Hence it is necessary either to remove any new
product introduced in the previous steps of the analysis, or if
any such remain, to be able to estimate its quantity with pre-
cision. In decomposing the muriate of lime by oxalate of am-
monia, muriate of ammonia is substituted, which can be after-
wards dissipated by heat. The object, therefore, is to decom-
pose the muriate of magnesia, and remove the magnesia, either
by some similar method, or, if not, by some other in which the
muriate substituted can be accurately estimated ; and to attain

one or other of these conditions, gives rise to the difficulty to
which I have alluded.

The

* The only source of error to which this step of the analysis is liable, is that
which will arise if more barytes has been used in the first operation, than
was necessary to precipitate the sulphuric and carbonic acids. It will be
thrown down in the state of oxalate of barytes, and be converted into carbo-
nate and sulphate, and thus give the apparent proportion of lime too large.
This is obviated, of course, by taking care to avoid using an excess of bary-
tes. To render the operation of the oxalate of ammonia as perfect as possible
in precipitating the lime, the water should be considerably reduced by evapora-
tion, taking care to avoid any separation of any of its ingredients.

ae

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ANALYSIS OF MINERAL WATERS. 267

The decomposition of the magnesian salt by ammonia would
have the former advantage, as the muriate of ammonia would
be expelled at the end of the process by heat; but this de-
composition, it is well known, is only partial. Sub-carbonate
of ammonia causes a more abundant precipitation of magnesia,
but still its action is likewise partial, a ternary soluble salt be-
ing formed after a certain quantity has been added. It seem-
ed probable, that this might be obviated, by adding the sub-

carbonate of ammonia as long as it occasioned any precipita-
‘ tion, then evaporating the clear liquor to dryness, expelling

the muriate of ammonia, and any excess of ammonia, by heat,
re-dissolving, and again adding the sub-carbonate of ammonia
to decompose the remaining magnesian salt. Proceeding in
this way, I found that a copious precipitation took place on the
second addition, and even at the fourth a small quantity of
precipitate was thrown down. But the decomposition, after
all, was not perfect, for the quantity of magnesia obtained was
not equal to what was procured by other methods.

Sub-carbonate of soda or potash has been usually employed
to precipitate magnesia from its saline combinations. The
precipitation, however, is only partial, unless an excess of the
precipitant be employed (and even then, perhaps, is not alto-
gether complete); and as this exces cannot easily be estima-
ted, it introduces a source of error in estimating the quantity
of muriate of soda at the end of the operation, against which it
is not easy to guard.

The method proposed by Dr Woxtaston, of precipitating
magnesia from its solution, by first adding carbonate of am-
monia, and then phosphate of soda, so as to form the insoluble
phosphate of ammonia and magnesia, is one much more per-
fect ; the whole of the magnesia appears to be precipitated,
and as a method, therefore, of determining the quantity of this.

L112 base,

268 A GENERAL FORMULA FOR THE

base, it is probably unexceptionable. It does not, however,
altogether accord with the object of the present formula. The
soda of the phosphate of soda serves to neutralize the muriatic
acid of the muriate of magnesia ; a quantity of muriate of soda
is of course formed, which remains with the muriate of soda of
the water, and the amount of which, therefore, it is necessary
to determine with accuracy. This may be done from the
quantity of phosphate of magnesia obtained giving the equiva-
lent portion of muriate of soda, either by means of the equiva-
lents of the acids, or of the bases. But still this renders the
method somewhat complicated ; and it may be liable to some
error, if any excess of phosphate of soda be added, which, in
order to precipitate the magnesia entirely, it may be difficult
to avoid ; this excess remaining with the muriate of soda, and
rendering the estimate of it incorrect. And independent of
these circumstances, it would be preferable to give uniformity
to the operation, by employing some method by which the
product in this, as well as in the previous steps, is removed, at
the end of the analysis, leaving only the muriate of soda.

It seemed probable that this might be attained, by employ-
ing phosphoric acid with the carbonate of ammonia, to form
the triple phosphate of ammonia and magnesia, such an excess
of ammonia being used, as should both be sufficient for the
constitution of this compound, and for the neutralization of the
muriatic acid of the muriate of magnesia; muriate of ammo-
nia would thus be substituted, the same as in the preceding
step of precipitating the lime, which at the end would be ex-
pelled by heat, leaving muriate of soda alone. I accordingly
found, that when this variation of the process was employed,
the clear liquor, after the precipitation, was-not affected by the
addition either of phosphate of soda with ammonia, or of sub-
carbonate of soda,—a proof that the separation of the magnesia

had

i i

Gilattie 20 te? 2

ANALYSIS OF MINERAL WATERS. 269

hhad been complete. To establish its accuracy with more cer-
tainty, the following experiments were also made.

Twenty grains of muriate of soda (pure rock-salt), which had
been exposed to a red heat, and ten grains of crystallised mu-
riate of magnesia, were dissolved in an ounce of water, at the
temperature of 100°. The phosphate of soda and carbonate
of ammonia were then employed .to precipitate the magnesia in
the mode proposed by Dr Worzasron, that is, a solution of
the ammoniacal carbonate was first added, and afterwards a so-
lution of phosphate of soda, as long as any precipitation was
produced, taking care to preserve in the liquor a slight excess
of the ammonia. ‘The precipitate being washed and dried, af-
forded, after exposure tod a red heat for an hour, 5.4 grains of
phosphate of magnesia, equivalent to 2.15 of magnesia. The
clear liquor being evaporated, muriate of soda was obtained,
which, after exposure to a red heat, weighed 25.77 grains.
Phosphate of magnesia being composed of 39.7 of magnesia,
with 60.3 of phosphoric acid, 5.4 grains of it are equivalent to
6.4 grains of muriate of soda, and this deducted from the quan-
tity obtained 25.7, leaves 19.3 as the quantity originally dissol-
ved. ,

- A solution perfectly the same was prepared, and a solution

‘of carbonate of ammonia was added to it as before. A strong

solution of phosphoric acid was then dropped in, as long as
any precipitation was produced, observing the precaution of

_ having always an excess of ammoniacal carbonate in the li-

quor. ‘The precipitate being washed and dried, afforded, after
exposure to a red heat, 5.5 grains of phosphate of magnesia
equivalent to 2.19 of magnesia. The clear liquor being evapo-
rated, and the dry matter being exposed to a heat gradually
raised to redness, weighed, when cold, exactly 20 grains.
ba ever In

270 A GENERAL FORMULA FOR THE

In both experiments, the quantity of muriate of soda is ac-
curately obtained, or as nearly so as can be expected. They
correspond, too, as nearly as can be looked for, even in a repe-
tition of the same experiment, in the quantity of magnesia
which they indicate. To ascertain how far this corresponded
with the real quantity, I converted 10 grains of the crystallised
muriate of magnesia into sulphate by the addition of sulphuric
acid, and exposed it to a low red heat; the product weighed
G.4 grains, equivalent to 2.13 of magnesia. This may be re-
garded as a perfect coincidence, and as establishing the accu-
racy of the other results *.

It thus appears, that phosphoric acid with an excess of am-
monia may be employed to precipitate magnesia from its sa-
line combinations ; and in a process such as the present, it has
the advantage, that the muriate of ammonia formed, can be af-
terwards volatilised by heat, and the quantity of any residual
ingredient can of course be easily ascertained. Neutral phos-
phate of ammonia would also have this advantage ; but it does
not succeed, phosphate of magnesia not being sufficiently inso-
luble. On adding a solution of phosphate of ammonia to a so-
lution of sulphate of magnesia, the mixture became turbid in
a minute or two, and in a short time a precipitate in crystal-
line grains formed at the bottom and sides; but it was not
considerable, and did not increase. Phosphate of ammonia,
however, with an excess of ammonia, or with the previous ad-
dition of carbonate of ammonia, may be employed with the

same

* According to the result of this last experiment, 100 grains of crystallised
muriate of magnesia would give 64 of real sulphate of magnesia, composed of
21.3 of magnesia, and 42.7 of sulphuric acid. This quantity of sulphuric acid is
equivalent to 29.4 of muriatic acid. Hence 100 grains of this salt crystallised
(in which state its composition, I believe, has not been determined) consist. of
21.3 magnesia, 29.4 muriatic acid, and 49.3 of water..

ANALYSIS OF MINERAL WATERS. 271

same effect as phosphoric acid. In applying the phosphoric
acid to this purpose under any of these forms, it is necessary
to be careful that it be entirely free from any impregnation of
lime. n

There is one other advantage which this method has, that if
even a slight excess of phosphoric acid be added, the error it
can introduce must be extremely trivial ; for the effect of it
will be only to decompose a small portion of the original mu-
riate of soda; and as the difference is very inconsiderable in
the proportion in which phosphoric and muriatic acids com-
bine with soda, any difference of weight which may arise from
this substitution, to any extent to which it can be supposed to
happen, may be neglected as of no importance *..

To

* For the sake of comparison, and to ascertain the accuracy of different me-
thods, I submitted a similar solution of muriate of magnesia and muriate of soda
to analysis by sub-carbonate of ammonia. ‘To the saline liquor, heated to 100°,
a solution prepared by dissolving carbonate of ammonia in water of pure ammo-

“nia, was added, until it was in excess. A precipitation rather copious took
place; the precipitate being collected on a filtre, the clear liquor was evaporated
to dryness, and the saline matter was exposed to heat, while any vapours ex-
haled. Being redissolved, a small portion remained undissolved, and on again
adding sub-carbonate of ammonia to the clear liquor, precipitation took place,
rather less abundant than at first. ‘This was repeated for a third, and even for
a fourth time, after which the liquor was not rendered turbid. Being evapora-
ted, the muriate of soda obtained, after exposure to a red heat, weighed 20.5
grains.. The whole precipitate washed, being heated with sulphuric acid, af-
forded of dry sulphate of magnesia 4.8 grains, a quantity inferior to that ob-
tained by the other methods, evidently owing to the less perfect action of the
ammoniacal carbonate as a precipitant. A similar deficiency in the proportion
of magnesia was found in the analysis of sea-water by sub-carbonate of ammo-
nia, as has been already stated; while, on the other hand, in its analysis by
phosphate of soda and carbonate of ammonia, a larger quantity of muriate of so-
da was obtained than by the other methods, probably from the difficulty of
avoiding an excess of phosphate of soda in precipitating the magnesia.

272 A GENERAL FORMULA FOR THE

To apply this method, then, to the present formula; add to
the clear liquor poured off after the precipitation of the oxa-
late of lime, heated to 100°, and, if necessary, reduced by eva-
poration, a solution of carbonate of ammonia; and immediate-
ly drop in a strong solution of phosphoric acid, or phosphate
of ammonia, continuing this addition with fresh portions, if
necessary, of carbonate of ammonia, so as to preserve an ex-
cess of ammonia in the liquor as long as any precipitation is
produced. Let the precipitate be washed ; when dried by a heat
not exceeding 100°, it is the phosphate of ammonia and mag-
nesia containing .019 of this earth ; but it is better for the sake
of accuracy, to convert it into phosphate of magnesia by calci-
nation for an hour at a red heat: 100 grains, then, contain 40
of magnesia.

Evaporate the liquor remaining after. the preceding opera-
tions to dryness, and expose the dry -mass to heat as long as
any vapours exhale, raising it towards the end to redness.
The residual matter is muriate of soda, 100 grains of which
are equivalent to 53.3 of soda, and 46.7 of muriatic acid. It is
not, however, to be considered necessarily as the quantity of
muriate of soda contained in the water; for a portion of soda
may have been present above that combined with muriatic
acid, united, for example, with portions of sulphuric or carbo-
nic acid ; and, from the nature of the analysis, this, in the pro-
gress of it, or rather in the first step, that of the removal of
these acids by the muriate of barytes, would be combined with
muriatic acid. It does not, therefore, give the original quan-
tity of that acid; but it gives the quantity of Sopa, since no
portion of this base has been abstracted, and none introdu-
ced.

The quantity of muriatic acid may have been either greater
or Jess than that in the muriate of soda obtained. If the quan-

tity

ANALYSIS OF MINERAL WATERS. 273

tity of soda existing in the water exceeded what the propor-
tion of muriatic acid could neutralise, this excess of soda being
combined with sulphuric or carbonic acid, then, in the remo-
val of these acids by muriate of barytes, muriatic acid would
be substituted, which would remain in the state of muriate of
soda ; and if the quantity considered as an original ingredient
were estimated from the quantity of this salt obtained, it would
be stated too high. Or if, on the other hand, more muriatic
acid existed in the water than what the soda present could
neutralise, the excess being combined with the other bases,
lime or magnesia, then, as in the process by which these earths
are precipitated, this portion of the acid would be combined
with ammonia, and afterwards dissipated in the state of muri-
ate of ammonia, if the original quantity, were inferred from
the weight of the muriate of soda obtained, it would be stated
too low. .

To find the real quantity, therefore, another step is necessa-
ry. The quantities of bases, and of acids procured, (taking
the quantity of muriatic acid existing in the muriate of soda
obtained), being combined according to the known proportions
of their binary combinations, if any portion of muriatic acid
has been abstracted, the bases will be in excess, and the quan-
tity of this acid necessary to produce neutralization, will be
the quantity lost ; or, on the other hand, if any portion of mu-
riatic acid has been introduced, and remains beyond that ori-
ginally contained in the water, this quantity will be in excess
above what is necessary to produce neutralization. The simple
tule, therefore, is to combine the elements obtained by the
analysis, in binary combinations, according to the known pro-
portions in which they unite ; the excess or deficiency of mu-
riatic acid will then appear; and the amount of the excess
being subtracted from the quantity of muriatic acid contained

Vou. VIII. P. 1. Mm in

974 A GENERAL FORMULA FOR THE

in the muriate of soda obtained, or the amount of’ the deficit
being added to that quantity, the real quantity of Murzartic
Aci will be obtained *.

There is one deficiency, however, in this method. If any
error has been introduced in any previous step of the analysis,
either in the estimation of the bases or of the acids, this
error will be concealed by the kind of compensation that is
made for it, by thus adapting the proportion of muriatic acid,
to the results such as they are obtained ; and at the same time,
an incorrect estimate will be made of the quantity of muriatic
acid itself. When any error, therefore, can be supposed to ex-
ist, or, independent of this, to ensure perfect accuracy, it may
be proper to estimate directly the quantity of muriatic acid in
a given portion of the water, by abstracting any sulphuric or
carbonic acid by nitrate of barytes, and then precipitating the
muriatic acid by nitrate of silver or nitrate of lead. The real
quantity will thus be determined with perfect precision, and
the result will form a check on the other steps of the analysis,
as it will lead to the detection of any error in the estimate of
the other ingredients ; for when the quantity is thus found, the
quantities of these must bear that proportion to it which will
correspond with the state of neutralization.

Thus, by these methods, the different acids, and the differ-
ent bases are discovered, and their quantities determined. To
complete the analysis, it remains to infer the state of combina-
tion in which they exist. It will probably be admitted, that
this must be done on a different principle from that on which
the composition of mineral waters has hitherto been inferred.
The compounds which may be obtained by direct analysis,

cannot

* The analysis of sea-water in a preceding paper, will afford an illustration
of this (page 237.)

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2 ee, Roe

ANALYSIS OF MINERAL WATERS. 275

cannot be considered as being necessarily the real ingredients,
and to state them as such would often convey a wrong idea of
the real composition. There are two views according to which
the state of combination in a saline solution may be inferred,
and in conformity to which, therefore, the composition of a
mineral water may be assigned. It may be supposed, that the
acids and bases are in simultaneous combinations. Or if they
be in binary combinations, the most probable conclusion with
regard to this, as I have already endeavoured to shew, (p. 230.)
is, that the combinations are those which form the most soluble

- compounds, their separation in less soluble compounds, on

evaporation, arising from the influence of the force of cohe-
sion. In either of these cases, the propriety of first stating as
the results of analysis the quantities of acids and bases obtain-
ed, is obvious. On the one supposition, that of their existing
in simultaneous combination, it is all that is to be done. On
the other supposition, the statement affords the grounds on
which the proportions of the binary compounds are inferred.
And there can be no impropriety in adding the composition
conformable to the products of evaporation. The results of
the analysis of a mineral water may always be stated, then, in
these three modes : Ist, The quantities of the acids and bases:
2dly, The quantities of the binary compounds, as inferred from
the principle, that the most soluble compounds are the ingre-
dients ; which will have at the same time the advantage of ex-
hibiting the most active composition which can be assigned,

and hence of best accounting for any medicinal powers the wa-
ter may possess : And, 3dly, The quantities of the binary com-
pounds, such as they are obtained by evaporation, or any other
direct analytic operation. The results will thus be presented
under every point of view.

Mm 2 It

276 A GENERAL FORMULA FOR THE

It is obvious that the process I have described, adapted to
‘the most complicated composition which usually occurs, is to

be modified according to the ingredients. If no lime, for ex-
ample, is present, then the oxalate of ammonia is not employ-
ed; and in like manner with regard to the others. I have al-
so supposed the usual and obvious precautions to be observed,
such as not adding an excess of any of the precipitants, bring-
ing the products to a uniform state of dryness, &c. having
mentioned only any source of error less obvious, or peculiar to
the process itself.

With regard to other ingredients, either not saline, or more
rarely present, it will in general be preferable, when their pre-
sence has been indicated by the employment of tests, or by re-
sults occurring in the analysis itself, not to combine the inves-
tigation to discover them with the general process above de-
scribed, but to operate on separate portions of the water, and
to make the necessary allowance for their quantities in es-
timating the other ingredients. ‘The quantity of iron, for ex-
ample, in a given portion of the water, may be found by the
most appropriate method. Silica will be discovered by the
gelatinous consistence it gives on evaporation, and forming a
residue insoluble in acids, but dissolved by a solution of pot-
ash. Alumina may be discovered in the preliminary application
of tests, by the water giving a precipitate with carbonate of am-
monia, which is not soluble, or is only partially soluble in weak
distilled vinegar, but is dissolved by boiling in a solution of»
potash, or by its precipitation from the water sufficiently eva-
porated by succinate of soda; or in conducting the process it-
self, it will remain in solution after the precipitation of the
lime by the oxalic acid, and be detected by the turbid appear-
ance produced on the addition of the carbonate of ammonia
previous to the addition of the phosphoric acid to discover the

magnesia.

!
P
»

ANALYSIS OF MINERAL WATERS. 277

magnesia. Its quantity may then be estimated from its preci-
pitation by carbonate of ammonia, or by other methods usual-

_ly employed. Silica will also be precipitated in the same

stage of the process ; its separation from the alumina may be
effected by submitting the precipitates, thoroughly dried, to
the action of diluted sulphuric acid. Potash when present,
which is very seldom to be looked for, will remain at the end,
in the state of muriate of potash. Muriate of platina will de-
tect its presence, and the muriate of potash may be separated
by crystallization from the muriate of soda.

. Ture is another mode in which part of the analysis may
be conducted, which, although perhaps a little less accurate
than that which forms the preceding formula, is simple and
easy of execution, and which may hence occasionally be admit-
ted as a variation of the process ; the outline of which, there--
fore, I may briefly state. |

- The water being partially evaporated, and the sulphuric and
carbonic acids, if they are present, being removed by the addi-
tion of muriate of barytes, and the conversion of the whole
salts into muriates effected in the manner already described ;
the liquor may be evaporated to dryness, avoiding an excess
of heat, by which the muriate of magnesia, if present, might be
decomposed ; then add to the dry mass six times its weight of
rectified alcohol (of the specific gravity at least of .835); and
agitate them occasionally during twenty-four hours, without

applying heat. The muriates of lime and magnesia will thus

be'dissolved, while any muriate of soda will remain undissol<
ved.

278 A GENERAL FORMULA FOR THE

ved. ‘To remove the former more completely, when the solu-
tion is poured off, add to the residue about twice its weight of
the same alcohol, and allow them to stand for some hours, agi-
tating frequently. And when this liquor is poured off, wash
the undissolved matter with a small portion of alcohol, which
add to the former liquors.

Although muriate of soda by itself is insoluble, or nearly so,
in alcohol of this strength, yet when submitted to its action
along with muriate of lime or of magnesia, a little of it is dis-
solved. ‘To guard against error from this, therefore, evaporate
or distil the alcoholic solution to dryness, and submit the dry
mass, again, to the action of alcohol in smaller quantity than
before ; any muriate of soda which had been dissolved will
now remain undissolved, and may be added to the other por-
tion ; or at least any quantity of it dissolved must be extreme-
ly minute. A slight trace of muriate of lime or of magnesia
may adhere to the muriate of soda, but when a sufficient quan-
tity of alcohol has been employed, the quantity is scarcely ap-
preciable ; and the trivial errors from these two circumstances
counteract each other, and so far serve to give the result more
nearly accurate.

Evaporate the alcohol of the solution, or draw it off by dis-
tillation. To the solid matter add sulphuric acid, so as to ex-
pel the whole muriatic acid ; and expose the residue to a heat
approaching to redness, to remove any excess of sulphuric acid.
By lixiviation with a small portion of water, the sulphate of
magnesia will be dissolved, the sulphate of lime remaining un-
dissolved, and the quantities of each, after exposure to a low
red heat, will give the proportions of lime and magnesia. The
quantity of soda will be found from the weight of the muriate
of soda heated to redness ; and the quantities of the acids will

be determined in the same manner as in the general formula.
This

ANALYSIS OF MINERAL WATERS. . 279°

This method is equally proper to discover other ingredients
which are more rarely present in mineral waters. Thus, alu-
mina will remain in the state of sulphate of alumina along
with the sulphate of magnesia, and may be detected by preci-
pitation by bi-carbonate of ammonia. Silica will remain with
the muriate of soda after the action of the alcohol, and will be
obtained on dissolving that salt in water. And iron will be
discovered by the colour it will give to the concentrated li-
quors, or the dry residues, in one or other of the steps of the
operation. .

6

Tue general process I have described may be applied to the
analysis of earthy minerals. When they are of such a compo-
sition as to be dissolved entirely, or nearly so, by an acid, that
is, where they consist chiefly of lime, magnesia, and alumina,
its direct application is sufficiently obvious; where they re-
quire the previous action of an alkali from the predomi-
nance of siliceous earth, on this being separated, the excess of
alkali may be neutralised by muriatic acid ; and the remaining
- steps of the analysis may be prosecuted, with any modification
which the peculiar composition will require. As the quanti-
ties of the ingredients are capable of being estimated with so
much precision, it may be employed with more peculiar ad-
vantage where a small quantity only of the mineral can be sub-
mitted to analysis; and when it is employed, such a quantity
only, ten grains, for example, ought to be made the subject of
experiment.

END OF PART FIRST.

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XV. On the Effects of Compression and Dilatation in altering
the Polarising Structure of Doubly Refracting Crystals.
By Davin Brewster, LL. D. F. B.S. Lon. & Enry.

(Read November 17. 1816.)

Ta a paper which I had the honour of submitting to the So-
ciety, at the end of last session, I gave a detailed account of
the effects of mechanical compression and dilatation, in com-
municating to glass and other uncrystallised bodies, all the
properties of doubly refracting crystals. I had at that time at-
tempted, without success, to alter the polarising structure of
doubly refracting crystals, although I applied the force of

_ powerful screws to Topaz, Rock-crystal, and Calcareous spar.

All the specimens which I employed were crushed to pieces
by the pressure, but exhibited no traces of the coloured. rings:
when exposed to polarised light.

‘The cause of the failure of these experiments did not occur
to me, till I was. engaged in examining the phenomena pro-
duced in the direction of the resultant axes of regular crystals.
I then saw, that the pressure formerly applied, had actual-
ly developed a new polarising force, but that it had been

Vou, VIII. P. II. Nn applied

982 ON THE EFFECTS OF PRESSURE IN ALTERING THE

applied at such an angle with the axis, that the compound force
arising from the combination of the new force with the ordi-
nary polarising force of the crystal, produced tints far beyond
the limits of Newron’s scale. In order, therefore, to observe
the influence of the polarising force generated by pressure, it
became necessary either to use a crystallised plate. which was
so thin as to exhibit tints within the limits of Newron’s scale,
or to apply the force at right angles to the axis, and to transmit
the polarised light, either along the axis, or at such an angle
with it as corresponded to a tint below the fifth or sixth order.

I therefore took a plate of Caleareous spar, (one of the nega-
tive class of crystals), bounded by planes perpendicular to the
axis of double refraction, or to the short diagonal of the primitive
rhomb; and having exposed it to polarised light, I observed
the beautiful system of circular and highly coloured rings
which it produced. The force of a screw was now applied to
the sides of the plate, and the rings instantly began to lose
their circular shape, to swell and contract in different places,
and to bend into curves of contrary flexure at the points of
pressure. By continuing the pressure, the plate was broken to
pieces.;

Instead of oriniding ppb the te obtuse solid snipes of
the rhomboid of calcareous spar, 1 took a complete hoes
and cemented upon two of its parallel surfaces a prism of flint-
glass, whose refracting angle was 45°. When a polarised ray
was incident almost vertically upon one of the faces of the
prism, so as to be refracted parallel to the diagonal of the
rhomb, the system of coloured rings was distinctly seen. I now
pressed. together, by means of screws, the other four parallel
surfaces of the rhomboid, and observed in a very satisfactory
manner the change of form induced upon the circular system of
rings.

Similar

POLARISING STRUCTURE OF DOUBLY REFRACTING CRYSTALS. 283

Similar experiments were made with Quartz, a crystal of the
positive class, and with various other crystals, both with one and
two axes of double refraction ; and in every case the tints were
either raised or depressed in the scale of colours. The same
effects were obtained at various angles with the axis, either by
reducing the thickness of the plates, or by bringing the tints
within the limits of Newron’'s nd by the opposite action of
plates of sulphate of lime.

~We may therefore consider it as an established fact, that the
phenomena produced by the polarising forces of all crystals,
whether they have one or more axes, and whether their action
is positive or negative, are very considerably affected by sub-
jecting the crystals to compressing or dilating forces.

The effect which we have now described may arise from
two causes, either from an actual modification of the original
polarising force of the crystal, or from the developement of a
new force, which merely combines its effects with those of the
original force. The first of these cases is exemplified, when
we subject to pressure a plate: of glass along which heat is in
the act of being transmitted. The pressure which is thus ap-
plied, alters the state of aggregation into which the glass is
thrown by the passing heat, and produces a real modification
of its former polarising force. When, on the other hand, we
combine a plate of sulphate of lime with a plate of didisaduis
spar, the resulting tint arises merely from a @ombination of
the tints which these crystals produce: separately ; ; the po-
larising foree’ of the calcareous spar remaining mie same as be-
fore.

In order to determine whether pressure modifies the origi-
nal force, or creates a new one in doubly-refracting Feil
I cut the crystals into different shapes, and found that the ef-
fect produced by pressure varied with the external shape of

Nn 2 the

284 ON THE EFFECTS OF PRESSURE IN ALTERING THE

the specimen, in the same manner as in plates of glass. Hence
it follows, that since the polarising force of crystals is in no re-
spect influenced by their external shape, a new and moveable
polarising force is generated by pressure, which increases or di-
minishes the effect of the permanent force, according to the di-
rection in which it is anplied. The effect, therefore, of a cry-
stallised plate subjected to pressure, is the same as if we com-
bined it, when free from pressure, with a similar plate of the
same substance, destitute of any polarising force, and pressed
in a similar manner. The force residing in the ultimate par-
ticles of the crystal is unchangeable, and the pressure deve-
lopes the new force, by merely altering their state of aggrega-
tion.

With the aid of these views, we may now predict all the
changes which can be produced upon positive and negative
crystals, by mechanical compression and dilatation.

When the two parallel surfaces of a transparent solid are
brought nearer each other by pressure, the tint, in the direction
of a line perpendicular to these surfaces, which may be called
the axis of compression, is negative, and therefore the polarising
force produced by compression is negative, like that of calcare-
ous spar, &c. When the two surfaces are, on the other hand,
separated from each other by dilatation, the tint in the direc-
tion of the perpendicular, which may be called the awis of di-

latation, is negative, and consequently the polarising force pro-

duced by dilatation is positive, like that of ztrcon, &c.

Hence, if we take plates of crystals, and apply the forces to
parallel surfaces, we shall obtain the results contained in the
following Table :

- TABLE

a

POLARISING STRUCTURE OF DOUBLY REFRACTING CRYSTALS. 285

~Tasze, shewing the Effect of Compression and Dilatation
upon Positive and Negative Crystals.

Axis of Compression or | Axis of Compression or
‘Dilatation parallel to Dilatation perpendicu-
the Axis of the Crys- | lar to the Axis of the
tal. © Crystal.

Positive crystals, compressed, | Tints rise, Tints descend.
dilated, Tints descend,| Tints rise.

Negative crystals, compressed, | Tints descend, | Tints rise.
~ —— dilated, Tints rise, Tints descend.

Now, since every compression is accompanied with a dilatation
in a direction perpendicular to the axis of compression, and
vice versa, it is obvious from the Table, that these simultane-

_ ous changes in the state of aggregation of the particles, will act

in combination, that is, they will conspire in producing either
a positive or a negative polarisation.

The preceding results, which are deducible, a priori, from
the principles already established, I have confirmed by direct
experiments upon calcareous ‘spar, quartz, and various other
doubly-refracting crystals, cut into different shapes ; and I have
obtained analogous results, by the application of pressure to
crystals with two axes of extraordinary refraction.

If the axis of compression is perpendicular to the axis of
double refraction, the crystal is converted into a crystal with
two axes, the poles of the two resultant axes or diameters of
no polarisation being distinctly visible.

The

286 ON THE EFFECTS OF PRESSURE, &c.

The tints discovered by M. Bior along the axis of Rock
Crystal, and supposed to arise from a rotatory motion of the
particles of light, suffer no other change from pressure, than
that which they experience by being combined with the tints
produced by any other crystal.

When the state of aggregation of the particles of doubly-re-
fracting crystals, is altered by the agency of heat, their polar-
ising forces suffer analogous changes ; but these changes are less
perfectly developed than in glass, owing to the great conduct-
ing power of regularly crystallised bodies.

XVI.

ES a

XVI. Experiments on Muriatic Acid Gas, with Observations on

its Chemical Constitution, and on some other Subjects of
Chemical Theory. By Joun Murray, M. D.F.R.S.E.

(Read 15th Dec. 1817, and 12th Jan. 1818.)

PART J.

Sone years ago J proposed, as decisive of the question which
has been the subject of controversy on the nature of Oxymu-
riatic and Muriatic Acids, the experiment of procuring water
from muriate of ammonia, formed by the combination of dry.
ammoniacal and muriatic acid gases. Muriatic acid gas be-
ing the sole product of the mutual action of oxymuriatic gas

- and hydrogen, it foHows, that if oxymuriatic gas contain oxy-

gen, muriatic acid gas must contain combined water ; while, if
the former be a simple body, the latter must be the neal acid,
free from water. When muriatic acid gas is submitted to the
action of substances which combine with acids, water is obtain-
ed ; but though the most simple and direct conclusion from
this is, that the water is deposited from the muriatic acid gas,
the result may be accounted for on the opposite doctrine, by
the

288 EXPERIMENTS AND OBSERVATIONS

the supposition, that it is water formed by the combina-
tion of the hydrogen of the acid with the oxygen of the
base. Ammonia, however, containing no oxygen, if water
is obtained from its combination with muriatic acid gas, we
obtain a result which cannot be accounted for on this hypothe-
sis, but must be regarded as a proof of the presence of water in
the acid gas. And this, again, affords a proof equally conclu-
sive of the existence of oxygen in oxymuriatic gas.

The results of the experiment which I had brought forward,
were involved in much controversial discussion: And a brief
recapitulation of the objections that were urged to it, is neces-
sary, as an introduction to the experiments I have now to sub-
mit; and to the consideration of the present state of the ques-
tion.

The original experiment was performed by combining thir-
ty cubic inches of muriatic acid gas, with the same volume of
ammoniacal gas carefully dried. The salt formed was exposed
in a small retort with a receiver adapted to it, to a moderate
heat gradually raised. Moisture speedily condensed in the
neck of the retort, which increased and collected into small
globules *. ; Cy anew

This result was admitted by those who defended the new
doctrine, when the experiment was performed in the manner I
have described,—water being obtained, it was allowed “ in no
inconsiderable quantity.” But, to obviate the conclusion, it was
asserted, that this is water which has been absorbed by the salt
from the atmosphere. This was affirmed by, Sir Humpnry Davy,

who stated that the salt absorbs water in this manner to a very:

considerable extent; that it is only from the salt in this state
that water can be procured, and that when it is formed from
the

# Nicwoxson’s Journal, vol. xxxi. p. 126.

———_ ee eee

ON MURIATIC AcID Gas, &e. 289

the combination of the gases in a close vessel, and heated with-
out exposure to the air, not. the slightest trace of water ap-
pears, even when the experiment is performed on a sa
scale.

The reverse of this I was able to demonstrate by farther ex-
perimental investigations. It was shewn, that the salt absorbs
no moisture from the air in the common state of dryness and
temperature in which the experiment is performed: when
weighed immediately on its formation, in an exhausted vessel,
it gains no weight from exposure, but remains the same after
a number of hours ; and when exposed to the air in the freest
manner, it remains, after many days, perfectly dry. It was far-
ther shewn, that when the other circumstances of the experi-
ment are the same, it yields no larger portion of water when it
has been exposed to the air, than it does without this previous
exposure. And, lastly, it was proved, that when the salt has

been formed, and is heated without the air having been admit-

ted, water is obtained from it. This last result was even at
length admitted by those who had advanced the opposite as-
sertion, in an experiment performed with a view to determine
the fact. The quantity of water was indeed less than what is
procured in the other mode; but this was obviously owing to
the circumstances of the experiment being unfavourable to its
expulsion,—more particularly to the difficulty of applying a re-
gulated temperature to a thin crust of salt, so as to separate
the water without volatilising the salt itself,—and to the effect
arising from the whole internal surface of a large vessel being
encrusted with the salt, so that if the’ heat is locally applied,
the aqueous vapour expelled from one part is in a great mea-
sure condensed and absorbed at another, or if the heat is ap-
plied equally, is retained in the elastic form, and, as it is cool-

ed, is equally condensed.. Accordingly, when the experiment
Vou. VIII. P. II. Oo . was

290 EXPERIMENTS AND OBSERVATIONS

was repeated, obviating these sources of error as far as pos-
sible, the water obtained was. in larger quantity. And as no
fallacy belongs to the conducting the experiment in the more
favourable mode in which it was first performed, (the assertion
of the absorption of water from the air being altogether un-.
founded), the quantity procured in that mode is to be regarded
as the real result *.

The argument was inaintained; that the water might be deri-
ved from hygrometric vapour in the gases submitted to expe-
riment. This it was easy to refute. Dr Henry had shewn,
that ammonia after exposure to potash, and muriatic acid after
exposure to. muriate of lime, retain no trace of vapour what-
ever. And these precautions had been very carefully observed.
The assertion was brought forward, too, only to account for the
minute quantity of water obtained in that mode of conducting
the experiment which affords the least favourable result, and
were it even admitted to all the extent to which it can be sup-
posed to exist, is inadequate to. account for the larger en
obtained in the other.

That the entire quantity of water contained in the muriatic
acid gas, is not to be looked for, is evident from the nature of
the ammoniacal salt, particularly its volatility, whence the due
degree of heat to effect the separation of the water cannot be
applied. If the other muriates yield the greater part of their
water, only when raised nearly to a red heat, (which is the
case), it is not to be supposed that muriate of ammonia ‘shall
do so at a temperature so much lower, as that which it can su-
stain without volatilization. What is to be expected, is a cer-
tain portion of water, greater as the arrangements employed
are better adapted to obviate the peculiar difficulty attending

; ‘the

* Nicrotson’s Journal, vol. xxxik p..196, &c. ; vol. -xxxiv. p. 271.

1 ae

{> —*

4
;
|
|
;
:

ON MURIATIC ACID Gas, &c. - 29):

the experiment. There is a production of water in every form
of it; and there exists no just argument whence it can be in-
ferred, that the quantity is less than what ought to be ob-
tained. On the opposite doctrine, none whatever should ap-
pear.

To effect the more perfect separation of the water from the
muriate of ammonia, I had performed the additional experi-
ment of passing the salt formed from the combination of the
two gases, in vapour through ignited charcoal, on the principle
that by the interposition of the charcoal, the transmission of
the vapour would be impeded, and it would be exposed toa
more extensive surface, at which a high temperature would
operate, while some effect might also be obtained from the af-
finities exerted by the carbonaceous matter. To remove any
ambiguity from the effect of the charcoal, it was previously ex-
posed in an iron tube toa very intense heat, until all produc-
tion of elastic fluid had ceased ; and removed, while still warm,
into a tube of Wedgwood’s porcelain, containing the muriate
of ammonia, which was then placed across a furnace, so as to
be raised to a red heat. As soon as the vapour of the salt
passed through the ignited charcoal, gas was disengaged, which
was conveyed by a curved glass tube adapted to the porcelain
one, and received in a jar ovez quicksilver. Moisture was at
the same time pretty copiously deposited, condensing both in
the glass-tube in globules, and being brought in vapour with
the gas which it rendered opaque, and condensing on the sur-
face of the quicksilver within the jars. The elastic fluid con-
sisted of carburetted hydrogen, and carbenic acid, products
evidently of the decomposition by the ignited charcoal of a
portion of the liberated water. In this experiment, then, the
result was still more satisfactory than in the other. That no
ambiguity arose from any effect of the charcoal in affording

Oo 2 water,

992 EXPERIMENTS AND OBSERVATIONS

water, is evident from this, that the water appeared at the mo-
ment the salt began to pass in vapour, and at a temperature
far below that at which the charcoal had ceased to afford any gas.
In another variation of the experiment, muriate of ammonia
was passed in vapour, through an ignited porcelain-tube alone.
Water was obtained in larger quantity than when the salt had
been exposed to a heat short of its volatilization ; and even the
salt which had yielded water by that operation, afforded an ad-
ditional quantity in this mode,—a proof of the more perfect se-
paration of the water by the effect of a higher temperature *.

By all these results, then, 1 consider the existence of water
in muriate of ammonia, and of course in muriatic acid gas, as
demonstrated. .

Dr Une has lately laid before the Society the result of ano-
ther mode of conducting the experiment,—that of subliming
the muriate of ammonia\over some of the metals, at the tem-
perature of ignition. Water is thus stated to be obtained in
considerable quantity, with a production of hydrogen gas.

No objection appeared to Dr Urr’s experiment, except, per-
haps, that the salt operated on, was not that formed by the di-
rect combination of its constituent gases, but the common sal
ammoniac, in which water might be supposed to exist, either
as an essential, or an adventitious ingredient, as it is abundant-
ly supplied to it in the processes by which it is formed. I had
found, indeed, in some of my former experiments}, that sal
ammoniac yields no water when exposed to a heat sufficient to
sublime it, but affords it only when exposed to a red heat by
transmission of its vapour through an ignited tube,—that,
_ therefore, (owing no doubt to its previous sublimation,) it con-
- tains

* Nicuorson’s Journal, vol. xxxi. p. 129. + Id, vol. xxxiv. p. 274,

“ ON MURIATIC ACID Gas, &c. 293

tains apparently even less water than the salt formed by the
combination of the two gases. Still, objections entitled to less
consideration than this one, had been maintained in the course
of this controversy. I therefore thought it right to repeat the
experiment, with the necessary precaution to obviate it, and to
observe the actual result.

Thirty grains of muriate of ammonia, formed from the com-
bination of muriatic acid and ammoniacal gases, were put into
a glass tube with a slight curvature. Two hundred grains of
clean and dry iron filings were placed over it. The tube was
put'in a case of iron with sand, and placed across a small fur-
nace, so that the middle part, where the iron filings were, was
at'a red heat, the extremity, terminating in the mercurial

trough. The salt, from the heat reaching the closed extremi-

ty of the tube, soon passed in vapour through the ignited iron.
Gas issued from the extremity, and moisture appeared in the
cold part of the tube. A large quantity of gas was collected,
which had the odour quite strong of muriatic acid, and was in
part condensed by water; the residue burned with the flame of
hydrogen. The tube, for several inches, was studded with glo-
bules of water, and was bedimmed with vapour farther. I did
not prosecute the experiment, so as to ascertain the weight of
water produced, as' I had other experiments in view, which I
conceived might afford more conclusive results. But it proves
the point. it was designed to establish, that water is obtained’
from the salt formed by the combination of the gases, as well
as from the common sal ammoniac.

My: attention having been thus recalled to the subject, I have
again executed the experiment in its original and simplest:
form,—that of obtaining water from the salt by heat alone;
and to this I was led more particularly, as it had occurred to
me, that a more perfect abstraction of its water might be ef-

fected,

294 EXPERIMENTS AND OBSERVATIONS

fected, by conducting the experiment in an apparatus some-
what on the principle of the instrument invented by Dr Wot-
LAsToN, which he named the Cryophorus. In a retort of the
capacity of seven cubic inches, fitted with a stop-cock, and ex-
hausted, sixty cubic inches of ammoniacal gas were combined
with the requisite quantity of muriatic acid gas, each previous-
ly carefully dried,—the former by exposure to potash, the lat-
ter by-exposure to muriate of lime. . The stop-cock was then
detached from the retort ; the excess of ammoniacal gas was
removed by a caoutchouc bottle, and replaced by atmospheric
air; the salt was pushed down from the neck ; and it was con-
nected with another similar retort, the joining of the two be-
ing secured by cement. This last retort was also fitted with a
stop-cock adapted to a tubulature at its curvature,and heat be-
ing applied to it, a little of the included air was allowed to
escape. It was then placed in a mixture of muriate of lime and
ice, while the other, containing the muriate of ammonia, was pla-
ced in warm oil. The heat of this was raised to 420° ef Fahrenheit:
moisture condensed at the upper.part of the neck, when the
heat had.been raised to 220°, and continued for some time to
increase. It then diminished, from the continued application
of the heat, :carrying it forward. into the cold retort, and at the
end of the.experiment a considerable part of the body of this
was encrusted with.a thin film of ice. This result, therefore,
coincides entirely with what had been before obtained *.

Another

* A foreign chemist, who has continued to support the old doctrine of the na-
ture of muriatic acid, has observed, (Annals of Philosophy, vol. viii. p. 204.) that
the water of the muriatic acid gas cannot be supposed to be obtained by the
combination of the acid with ammonia, for no neutral ammoniacal salt, he adds,
can be obtained free from water, and the water of the acid gas becomes the wa-

ter

ON MURIATIC ACID GAs, &c. 295

Another form of experiment occurred to me still more di-
rect and simple, that of transmitting muriatic acid in its gase-
ous form over ignited metals. If water be obtained in this ex-
periment, it is a result which would prove subversive of the
new doctrine ; for muriatic acid gas is held to be the real acid,

free from water, and the only change which can happen, is that
ea. of

il ae i a te

ter essential to the salt. I did not think it necessary to make any reply to this
observation, founded entirely, as it appeared to me, ona mistaken assumption.

- But I may take this opportunity of remarking, that there is no necessary truth
in the supposition that, the ammoniacal salts must contain water which they can-
not yield. When acids combine with bases, the water of the acid does not ne-
cessarily remain in the compound. © On the contrary, it is capable of being dri-
ven off from the greater numberof them, by an elevated’ temperature ; and there
is no principle on which it can be inferred, that: ammonia should in this respect
be different from other bases. That it is incapable, as the same chemist remarks,
(Annals, vol. vii. p. 434.) of combining with a dry acid, so as to.form a neutral
compound, is of no weight ; for the same thing is true of other Bases, which yet,
when combined with such an acid by the aid of water, allow this water to escape
from the combination. He. himself observes, that well-burnt lime, free. from:
water, does not absorb dry: carbonic acid gas, but absorbs it rapidly if aqueous
vapour be admitted, though water is not retained in the composition of carbo-
nate of lime. And F have found, that dry magnesia does not absorb muriatic
acid gas; though with the aid of water it forms a combination from which the
water can be expelled: by heat.. That, ammoniacal salts exist without water, is.
evident from the combination of carbonic acid gas and ammoniacal gas, being
effected with the greatest facility ; ; and the circumstance that this compound is
aot neutral, is one not depending on the peculiarity of the ammonia, and its not
containing water, like other bases, but on that.of the carbonic acid, which, with
all the alkalis, e even where water is present, has.a tendency to form compounds.

with excess of base. The reason why the ammoniacal salts do not yield the
eombined water of their acids so conipletely as that. of other salts, is, that from
their volatility, or their susceptibility of decomposition, they do not bear that de-
gree of heat which is necessary to produce it. I cannot, therefore, but consider
the observation alluded to, as one altogether unfounded, and which ought not on
mere speculation to have been brought forward against a positive result.

Q

Sapefi

296 EXPERIMENTS AND OBSERVATIONS ©

of the-metal decomposing the acid, attracting its chlorine and
liberating its hydrogen. And the experiment is farther free
from the only resource which remained to the advocates of
that doctrine, in the case of water being obtained from mu-
riate of ammonia, that it might be derived from the decompo-
sition of the elements of ammonia, regerding it as an alkali
containing oxygen. If water were really obtained from the
combination of muriatic acid and ammoniacal gases, it would
rather indicate, it was said, the decomposition of nitrogen
than the existence of water as a constituent of muriatic acid.
No weight, I believe, is due to such an assumption, but if any
importance were attached to it, it is precluded if water is ob- _
tained from the action of metals on muriatic acid gas.

I have executed the experiment in several forms; and in all
with a more or less satisfactory result.

One hundred grains of iron filings, clean and dry, were
strewed for a length of five or six inches, in a glass-tube which
was placed in an iron case, across a small furnace, so as to ad-
mit of being raised to a red heat. This tube, of about two
feet in length, was connected with a wide tube eight inches
Jong, containing dry and warm muriate of lime; and this was
farther connected, at its other extremity, with a retort afford-
ing muriatic acid gas, from a mixture of super-sulphate of pot-
ash and muriate of soda. The open extremity of the long
tube, dipped by a slight curvature in quicksilyer. On the iron
being raised to ignition, and the transmission of the acid gas
being conducted slowly, elastic fluid escaped from the extre-
mity of the tube, which was found to be hydrogen, and though
no trace of moisture appeared in the anterior part of the tube,
it immediately condensed in that part which was cold, beyond
the iron filings. This accumulated in globules, and at length

run

ON MURIATIC aciD Gas, &c. 297

run into a small portion in the bottom ; the sides were bedew-
ed for a length of six inches, and a thin film of moisture ap-
peared beyond, nearly its whole length.

By the muriatic acid gas being extricated in the preceding
experiment from nearly dry materials, and by its previous
transmission over an-extensive surface of loose muriate of lime,
it was inferred, that it would be free from hygrometric vapour ;
and that it held no moisture, was apparent from no trace of it
appearing in the anterior portion of the tube. To obviate,
however, entirely, any ‘supposed fallacy from this source, the
experiment was performed in the following manner. One
hundred grains of clean and perfectly dry iron filings were put
into a long glass tube, which was placed, as before, across a
small furnace. Muriatic acid gas had been kept in contact
with dry muriate of lime for three days, in a jar with a stop~
cock adapted to it. This was connected, by a short tube with
a caoutchouc collar, with the tube containing the iron filings ;
and a little of the muriatic acid gas being passed through the
tube to expel the air, the temperature was raised to ignition,
The slow transmission of the gas was continued by the pres-
sure of the mercury in the quicksilver trough, and fresh quan-
tities, which had been equally with the other exposed to mu-
riate of lime, were added, as was necessary. Water almost im-

‘mediately appeared in the tube beyond the iron filings, it col-

lected in spherules, and continued to accumulate as the gas

continued to be transmitted for a length of about seven inches.

A portion of the gas which escaped from the extremity, was

_ clouded, and deposited a film of moisture on the sides of the

jar in which it was received over quicksilver. The quanti-
ty of gas transmitted amounted to about thirty-five. cubic
inches.

Vou. VIL P. U.. Pp There

298 EXPERIMENTS AND OBSERVATIONS

‘There are some difficulties in conducting the experiment in
the manner now described, from the consolidation of the me-
tallic matter, and the volatilization of the product. It was
also of some importance to vary the experiment. I therefore
performed it in another mode. Metals scarcely act on muria-
tic acid gas, at natural temperatures, but from such a degree
of heat as could be applied by a small lamp, both iron and zine
were acted on; the gas suffered diminution of volume, hydro-
gen was formed, and a sensible production of moisture took
place. The simplest mode of exhibiting this, is to introduce
iron or zinc filings, previously dry, and warm, into a retort
fitted with a stop-cock ; exhausting it ; then admitting dry mu-
riatic acid gas ; and applying heat, by a small lamp, to the filings
in the under part of the body of the retort. Moisture soon
appears at its curvature in small globules, and increases on
successive applications of the heat with the admission of the
requisite quantities of gas.

To conduct the experiment, however, on a larger scale, I em-
ployed a different apparatus. A tubulated retort, of the capaci-
ty of twenty-five cubic inches, was connected with a jar, con-
taining muriatic acid gas in contact with muriate of lime, on the
shelf of the mercurial trough, by a tube bent twice at right
angles, and fitted by: its shorter leg with a collar of caoutchoue
to a stop-cock at the top of the jar, its longer leg passing into
the tubulature of the retort, so as to terminate within an
inch of its bottom, and the joinings being rendered air-tight.
The retort is so placed, that heat can be applied by a lamp to
the bottom, and its neck dips, by a short curved tube, under
a jar filled with quicksilver, which, by the reverted posi-
tion of the retort, may be placed beside the other, on the shelf
of the trough. At the commencement of the experiment, the
metallic filings, previously dry and warm, having been put into
the retort, the atmospheric air is expelled by a moderate heat,

and

ae MELA

ON MURIATIC-ACID Gas, &e. 299

and'small portions of the muriatic acid gas are admitted, until the
retort is filled with the pure gas. The stop-cock is then clo-
sed, and heat is applied by a lamp to the bottom of the retort,
under a considerable pressure-of mercury ; any small portion of
gas, expelled at the extremity, being received. in the small jar.
The heat. can thus be successively cautiously applied, and this,
as the experiment proceeds, to a greater extent, in consequence
of the diminution of volume that takes place. [Fresh quantities
of muriatic acid gas are admitted from time to time from the
jar, and the stop-cock being closed when the heat is applied,
the hydrogen gas produced is expelled, with-any muriatic acid
gas not acted on. ,
In the principal experiment I alae zine filings were
used i in preference to iron, from the. consideration, that muri-
ate of zinc is less volatile than muriate of iron, and therefore
sl admit of a- higher heat being applied to expel any wa-
- One hundred grains of clean and dry,zine filings were in-

el an warm, into the retort ; the air was expelled, and
muriatic acid gas was admitted from the jar. On applying
heat: to the zinc, the retort, which was before perfectly dry, was
bedimmed with moisture at its curvature, and small spherules
collected at the top of the neck. These increased in size, and
extended farther as the experiment advanced. After.a certain
time, part of this disappeared in the:interval of cooling, being
absorbed by the deliquescent product ; but when the heat was
again applied, it was renewed, and this in increased quantity,
until at length, at the end of four days, during which heat had
been frequently applied, the whole tube of the retort, seven
inches in length, was studded with small globules of fluid.
When the heat had been raised high, a beautiful arborescent
crystallization appeared in a thin film on the body of the’re-
tort, but no part of ‘this reached the neck. The retort was
now. detached ; the gas it contained was withdrawn by a caout-
Pp2 chouc

300 EXPERIMENTS AND OBSERVATIONS

choue bottle ; a small receiver was adapted ; and a slight heat
having been applied, to expel a little of the air, the joining was
made close by cement. The receiver was surrounded with a
freezing mixture, and heat was applied by a choffer to the re-
tort, as far as: could be done, without raising dense vapours,
Globules of liquid, perfectly limpid, collected pretty copious-
ly towards the middle and lower part of the neck, and the re-
ceiver, on being removed from the freezing mixture, was co-
vered sntawinally with a film of moisture. ‘The globules in the
neck of the retort were absorbed by a slip of bibulous paper,
and the quantity was found to amount to 1.2 gr. The recei-
ver being dried carefully, and weighed, lost by the dissipation
of the moisture within, 0.4 grain. Distilled water, in which
the bibulous paper was immersed, was quite acid; it gave no
sensible turbidness on the addition of ammonia, or of carbo-
nate of soda, and held dissolved, therefore, merely pure muria-
tic acid. The mass in’ the retort was of a grey colour, with
metallic lustre, in loosely agg sregated laminae, somewhat flexi-
ble. It weighed 114.8 grains. Adding to this increase of
weight, which the zinc had gained, the weight of the water and
the hydrogen gas expelled, it gives a consumption of muriatic
acid gas of about 16.8 grains, equivalent to about 43 cubie
inches. Supposing the weight of water to be doubled, or near-
ly so, by saturation with muriatic acid, this gives the product
of water in the experiment, as equal to nearly one grain; or
about one-fifth of the whole quantity of combined water, which
muriatic acid gas is calculated to contain *.

™

® The action of the metals on the muriatic acid gas, taking place in the above
experiments at a heat comparatively moderate, it occurred to me, that they
might exert a similar action with no higher heat on the acid, in muriate of am-
: monia,

exqrs

ON MURIATIC ACID GAs, &c. 301

' In all the preceding experiments, water has been procured
from muriatic acid gas. It is obvious, that such a result can-
not be accounted for on the hypothesis, that-it is the real.acid
free from water, a compound merely of chlorine and hydrogen.
On the opposite doctrine, as muriatic acid in its gaseous: form.
is held to contain water, it may be supposed. to aa a portion
of it.
siltk may be cata however, in this, as it was in the ex-
periment of obtaining water from the muriate of ammonia by
heat, that the water produced is derived from hygrometric va-
pour in the gas. To obviate this, it is sufficient to recur to
the fact established by the experiments of Henry and Gay
Lussac, that muriatic acid gas contains no hygrometric vapour ;
and to the obvious result in the experiment, that no quantity
that can be assumed, would be adequate to account for the
quantity. ramen nibtaihied: The circumstances of the experi-
_ Ment,

monia, and that this might afford an easy mode of exhibiting the results. I ac-
cordingly found, that on mixing different metals with sal ammoniac in powdery,

- previously exposed to a subliming heat, and exposing the mixture to’ heat by a

lamp, so regulated as to be short of volatilization, the salt was decomposed, am-
moniacal gas was expelled, and moisture condensed in the neck of the retort ;
covering @ space of several inches with small, globules, and at length running
down. . The metals I employed were iron, zine, tin, and lead; 100, 150, or 200
grains of each metal, dry and warm, being mixed with 100 grains of the salt,,
likewise newly heated. To obviate any fallacy from common sal ammoniac be-
ing employed, I repeated the experiment with the salt formed from the combina-
tion of its two constituent gases, and obtained the same result. But although
this affords an easy mode of exhibiting the production of water, it is not favour-
able to obtaining a perfect result, the heated ammoniacal gas carrying. off a :con-
siderable post of the water deposited ; and accordingly, the quantity, instead.
of increasing as the experiment proceeds, at length diminishes, and the ammoni-
acal gas deposites a portion of water in passing through mercury, or in being con-
veyed through a cold tube.

302 EXPERIMENTS AND OBSERVATIONS

ment, too, are such as to preclude any such supposition ; and
this more peculiarly so, than in the experiment of obtaining’
water from the muriate of ammonia by heat; for in the present:
case, the acid gas is alone employed, while in the other there
isan additional equal volume of ammoniacal .gas, which may
be supposed to afford a double quantity of hygrometric vapour.:
In the latter, both the gases are condensed into a solid pro-»
duct, and any hygrometric vapour may be supposed to be li-
berated; but in the present experiment, there remains the hy-"
drogen gas, capable of containing hygrometric vapour, while.
the muriatic acid gas contains none ; and the quantity of it
thus transmitted over the ;humid surface, and expelled frem
the apparatus, must have carried off more vapour than the.
other, introduced at a lower temperature, could have convey-;
ed.._ These circumstances, independent of the quantity of wa-;
ter deposited, precluded the supposition of any deposition from, *
the condensation of hygrometric vapour. And there is no
other external source whence it can be derived. In this re-
‘spect nothing can be more satisfactory than the experiment
with the zinc in the apparatus described. The muriatic acid.
gas rises from dry mercury in contact with muriate of lime,’
passes through a narrow bent tube, thirty inches in length,
without exhibiting the slightest film of moisture, is received.
into the retort perfectly dry ; and when the action of the metal.
on it is excited by heat, humidity immediately becomes appa-:
rent in the curvature of the retort, and this even while the
gas is warm, and of course capable of containing more water
dissolved, than it could do in its former state ; and the quanti-.
ty increases as the experiment proceeds. No arrangement can
be supposed better adapted to prove, that any deposition of wa-
ter must be by separation from its existence in the gas in a
combined state. 3

‘cas But

' ON MURIATIC ACID GaAs, &c. 303

But though TI consider this conclusion as established, there

-is a considerable difficulty attending the theory of the experi-

ment. The result of water being obtained is actually different
from what is to be looked for, on the doctrine of muriatic acid
gas containing combined water ; and even when the fact is
established, the theory of it is not easily assigned. On that
doctrine, it must be held that in the action of metals:on muriatic
acid gas, the metal ‘attracts oxygen from: the water, the corre>
sponding hydrogen is evolved, and the oxide formed combines
with the- real acid. No water, therefore, ought to be deposi-
ted, for none is abstracted from the acid, but what is spent in:
the oxidation of the metal: This will be apparent, by attend-
ing to the proportions in a single example, from: the scale of
chemical equivalents: 100 grains of iron combine:with 29 of
oxygen, and in this state of oxidation unite with. 99 of real mu-
riatic acid. This quantity of acid exists in 131.8 of muriatic
acid gas, combined with 32.8 of water ; and this portion of wa-
ter contains 29 of oxygen with 3.8 of hydrogen... There is pre-
sent, therefore, exactly the quantity of oxygen.which. the me-

tal requires to combine with the acid; and no. water remains

above this: Or it may be idleagnated: under another point of
view. Muriatic acid gas is composed of oxymuriatic gas and
hydrogen. A: metal acting on it must attract the oxymuriatic

-acid,—that is, the muriatie acid-and oxygen, and liberate the

hydrogen. No water, therefore, aught to appear, more, on
this theory, than: on the other; but the real products in both
must be a dry muriate, or chloride, and hydrogen gas. In the
action of ignited metals on muriate of ammonia, it. is equally
evident,'on the same principle, that no water ought to be ob-
tained. . How, then, is the production of water to be account-
ed for ?
~-Though the water obtained in. these experiments cannot be
derived from hygrometric vapour in the gas, there.is another
view

304 EXPERIMENTS AND OBSERVATIONS

view under which it may be regarded as present, as an adven-
titious ingredient. The acid having a strong attraction to
water, may be supposed, in the processes in which it is usually
prepared, to retain a portion not strictly essential to its con-
stitution as muriatic acid gas, but still chemically combined,—
that is, combined with it with such an attraction as to be libe-
rated only when it passes into other combinations, and it may
be this portion which is obtained in the action of metals on
the gas ; the other portion, that essential to the acid, being suf-
ficient to produce the requisite oxidation of the metal.

The question with regard to the existence of water in this
state, Gay Lussac and Tuxnanp' have already determined.
From an extensive series of experiments, they found reason to
‘conclude, that muriatic acid gas, in whatever mode it is pre-
_ pared, is uniformly the same. From the quantity of hydrogen
gas which combines with oxymuriatic gas in its formation, it
follows, that it contains 0.25 of water, essential to its constitu-
tion. But the gas obtained by the usual processes, afforded,
they found, exactly 0.25 of water, when transmitted over. oxide
of lead, or combined with oxide of silver ; and the same com-
pounds are formed, as by the action of oxymuriatic acid on sil-
ver and lead in their metallic state. They prepared muriatic
acid gas, by heating fused muriate of silver with charcoal mo-
derately calcined. It contained just the same quantity of wa-
ter as muriatic acid obtained from humid materials, as it af-
forded the same quantity of hydrogen from the action of po-
tassium. And instead of being capable of receiving the small-
est additional portion of water, a single drop of water being in-
troduced into three quarts of it, did not disappear, nor even
diminish, but, en the contrary, increased in volume *, These

; facts

(6h SS eee ta ee,

* Recherches Physico-chimiques, t. ii. p. 133.

a

-ON MURIATIC AcID Gas, &c. 305

facts establish the conclusion, that. muriatic acid gas can re-
-ceive no additional-portion of water, but that which is essential
to it, and hence preclude the solution of the difficulty under
consideration by the opposite assumption. And it is to be re-
marked, that should even such a portion of water exist in the

| -gas, it cannot be supposed that the acid should carry this with

it into its saline combinations, and retain it so, that it should
not be expelled by heat. It cannot be supposed: to exist, there-
fore, in muriate of ammonia thus heated, and of course cannot
account for the water obtained. by. the action of the metals on
this salt..

When it is proved, that no extrinsic water exists in muriatic
acid gas, there remain apparently only two modes on which the
production of water can be explained,—either, that the metal
may require less-oxygen’ than is supposed:in combining with
the acid, so. that. a portion of water will remain undecomposed,
to be deposited:: or, that the oxide attracts more real acid, so
as to liberate a larger proportion of water.. The-first of these
suppositions is improbable, from the consideration of the law
which regulates:the combination of metallic oxides with acids,
—that the quantity of acid is proportional to the quantity. of
oxygen,. so that if an oxide were formed. in these cases, at-a
lower degree of oxidation, it would only combine with a pro-
portionally smaller quantity of acid, and the quantity of. water. .
detached from the combination: would be the same.

No improbability is attached to the second ‘supposition ; and
it has even some support from the consideration, that many
metallic saline compounds, form with. an: excess:of acid; and
that: it is difficult, with regard to a number of them, to procure
them neutral. Metallic muriates, with excess:of acid, seem in
particular to be established with facility. And although an ex-
cess of metal be present in the action exerted on. muriatic

Vor. VIE. P. I Qq acid

806 EXPERIMENTS AND OBSERVATIONS

acid gas, this may not prevent the formation of a super-muriate,
more especially as the excess is in the metallic form, and ex-
erts no direct action, therefore, on the real acid.

To ascertain if a super-muriate were formed in these cases,
the product obtained from the action of the muriatic acid on
the metal was raised to a heat as high as could be applied with-
out volatilization, so that no loosely adhering acid might re-
main, and the air in the retort was repeatedly drawn out by a
caoutchouc bottle. The solution from the residue both of iron
and zinc was very sensibly acid. Some fallacy. however, at-
tends this, from the circumstance, that the liquid state is ne-
cessary to admit of the indications of acidity, and in adding wa-
ter to produce this, a change occurs in the state of combina-
tion, in a number of the metallic muriates ; a super-muriate be-
ing formed, which remains in solution, and a sub-muriate being
precipitated, so that the acidity of the entire compound cannot
justly be inferred from that of the solution. I found, accord-
ingly, that on adding water to the product from the action of
the acid gas on zinc, this change occurs ; a little of a white pre-
cipitate being thrown down, while the liquor remained acid.
But the fallacy can be obviated, by adding only as much water
as produces fluidity, without subverting the combination. Por-
tions, therefore, of the residue were exposed to a humid atmo-
sphere, until by deliquescence, liquors were formed transpa-
rent, without any precipitation ; and these were strongly acid,
reddening litmus paper when it was perfectly dry and warm.
I farther found, that the product of the solution of zinc in li-
quid muriatic acid, when digested with an excess of metal, and
evaporated to dryness, afforded by deliquescence a liquor sen-
sibly acid. And in both cases, even when the solid product
was retained liquid by heat, acidity was indicated by litmus pa-
per. Lastly, What is still less liable to objection, the residue —

in

y
4
z
,
4
b
i
4

ON MURIATIC ACID Gas, &c. 307

in the experiment of heating the muriate of ammonia with the
different metals, afforded similar indications of acidity.

These results appear to establish the production of a super-
muriate in the action of these metals on the acid, and this ac-
counts for the appearance of a portion of water, since, suppo-
sing water to exist in muriatic acid gas, the quantity combined
with that proportion of acid which would establish a neutral
compound, is the quantity required to oxidate the metal to
form that compound ; and if any additional portion of acid en-
ter into union, the water of this must be liberated, or be at
least capable of being expelled.

It was of importance, in relation to this question, to ascer=
tain the quantity of hydrogen obtained from a given quantity.
of muriatic acid gas; for, if the whole water essential to the
acid is decomposed by the action of the metal, half the volume
of hydrogen ought to be obtained,—muriatic acid gas being
composed of equal volumes of oxymuriatic gas and hydrogen
gas. I made this repeatedly the subject of experiment, by heat-
ing zinc and iron in muriatic acid gas. There are difficulties.
in determining the proportion with perfect precision; but the
quantity of hydrogen always appeared to be less than the half;
and on an average, about twelve measures were obtained, when
thirty measures of the other had been consumed, a result con-
formable to the liberation of a portion of the combined water
of the gas.

Whether the production of water in these experiments is sa-
tisfactorily accounted for, on the cause now assigned, may be
subject of farther investigation. In the sequel, I shall have to:
notice another principle, on which perhaps it may fall to be
explained. Whether accounted for or not, it is obvious, that
the fact itself is not invalidated by the theoretical difficulty ;
and also, that in relation to the argument with regard to the na-

Qq2 ture

308 EXPERIMENTS AND OBSERVATIONS, Cc.

ture of muriatic and oxymuriatic acids, it remains equally con-
clusive. In the doctrine of the undecomposed nature of chlo-
rine, muriatic acid gas contains neither water nor oxygen, and
the metal employed certainly contains none. These are the only

substances brought into action, and it is impossible that water |

should be a product of their operation. On the opposite doc-
trine, water is held to exist in muriatic acid gas to the amount
of one-fourth of its weight ; and it is conceivable, that by some
exertion of affinities, a portion of it may be liberated. If we
were unable to explain the modus operandi, this would remain
a difficulty no doubt, but not, as in the opposite system, an im-
possible result.

It is to be admitted, indeed, that in none of these cases, is .

the entire quantity of water which must be supposed to exist
in muriatic acid gas obtained ; and so far the proof is deficient.

But neither from the nature of the experiments is this to be.

looked for ; and I give more weight to the argument, from ha-
ving always found certain portions of water to be procured,
while, on the opposite doctrine, there should be none. In
those cases where supposing water to be present in muriatic
acid gas, it ought to be obtained in the full quantity, it uni-
formly is so, though the proof from these is rendered ambigu-
ous, by the result being capable of being explained on a differ-
ent hypothesis.

PART

—~— ae

.

{ 309 ]

PART II.

OBSERVATIONS ON THE CHEMICAL CONSTITUTION OF MURIATIC ACID
GAS, AND ON SOME OTHER SUBJECTS OF CHEMICAL THEORY.

ApmirtTine water to be procured from muriatic acid gas in
those forms of experiment, direct or indirect, in which the
agency of no other substance that can afford it, is introduced,
the conclusion seems necessarily to follow, which forms the ba-
sis of one of the two systems under which the relations of oxy-
muriatic and muriatic acids have of late years been explained,
—that oxymuriatic acid is.a compound of muriatic acid with
oxygen; and that muriatic acid in its gaseous state, contains
combined water. This doctrine, accordingly, may be main-
tained, and may even perhaps be just. It is not, therefore,
from the consideration of any deficiency in its support, that I
depart from it in the following observations, but that I consi-
der the view I have to propose as perhaps more probable, or at
least as, on the whole, according better with the present state
of chemical theory. In a science such as Chemistry, the prin-
ciples of which rest, rather on probable evidence, than on de-
monstration, it is of importance to. present a -subject in every
point of view under which it may be surveyed ; and this must
serve as an apology for the speculations I have now to offer.

There

310 OBSERVATIONS ON MURIATIC ACID,

There are, I believe, only two arguments to which any
weight is due in support of the opinion that chlorine is a
simple substance, which by combination with hydrogen forms
muriatic acid. One is drawn from the analogy resting on the
general fact, sufficiently established, that acidity is in different
cases the result of the agency of hydrogen ; the other, from the
analogy in the chemical relations of chlorine and iodine.

Sulphur forms with hydrogen a compound unequivocally
acid. The compound radical of prussic acid Cyanogen, disco-
vered by the able researches of Gay Lussac, likewise acquires
acidity when it-receives hydrogen. . Acidity, therefore, is a
property not exclusively connected with oxygen; it is also
communicated by hydrogen; and when chlorine with hydro-
gen gas, forms muriatic acid gas, the agency exerted may be
considered as similar to that arising in other cases, of the pro-
duction of an acid from the action of hydrogen.

This is confirmed by the relations of iodine. It, too, forms
an acid by combination with hydrogen; and the chemical
agencies of iodine are in several other respects similar to those
of chlorine. When the one, therefore, is considered as a
simple body, (and there is no absolute proof that iodine is a

compound,) the other is, with probability, placed in the same

class. And certain analogies existing between sulphur and io-
dine, serve to connect and confirm these views. Each of them
forms an acid with hydrogen; each of them also forms an acid
with oxygen. But chlorine exhibits precisely the same points
of resemblance: with hydrogen, it forms muriatic acid;
with oxygen, it forms chloric acid. Its chemical relations, with
regard to acidity, being thus similar, seem to require the same

explanation to account for them.
These facts lead undoubtedly to views of chemical theory,
different from those which had before been established; and on
which

———

AND ON SOME SUBJECTS OF CHEMICAL THEORY. 311

which the old doctrine with regard to the nature of muriatic
and oxymuriatic acids rests. It may be well, therefore, to in-
quire how far they may modify the conclusions to be drawn,
admitting even that oxymuriatic acid contains oxygen, and that
_ Mnuriatic sabia gas affords water.

When water is obtained from muriatic avid gas, it does not
necessarily follow, that it has pre-existed in the state of water.
It is equally possible, a priori, that its elements may be pre-
sent in simultaneous combination with the acid, or its radical,
—that the acid is a ternary compound of a radical with oxy-
gen and hydrogen ; and that it is decomposed in those proces-
ses by which water is procured, the hydrogen, with the requisite
proportion of oxygen, combining to form water ; and its radical,
with any excess of oxygen, remaining in union with the sub-
‘stance by which the change has been effected.

If this view were adopted with regard to muriatic acid, the
same view might, on the same grounds, be applied to the
other acids which appear to contain water in intimate combi-
nation, and: in a definite proportion. And such an acid, the
radical and precise constitution of which are known, may be
best adapted to illustrate the hypothesis.

Sulphuric acid affords water when it is submitted to the ac-
tion of an alkaline base ; and the quantity of this water appears
to be definite, amounting to 18.5 in 100 of the strongest acid
which can be procured in an insulated state ; 100 parts of this
acid, therefore, are considered as composed of 81.5 of real acid,
(consisting of 32.6 of sulphur, and 48.9 of oxygen,) with 18.5
of water. But if, instead of this view of its constitution, it be
considered as a ternary compound of sulphur, oxygen, and hy-
drogen, its composition will be 32.6 of sulphur, 65.2 of oxy-
gen, and 2.2 of hydrogen. In those processes by which water
is obtained from it ;—in the action, for example, of an alkaline

base,

312 OBSERVATIONS ON MURIATIC ACID,

base, and subsequent exposure to heat, the composition is sub-
verted by the affinities exerted; the hydrogen unites with the
requisite proportion of oxygen, forming water, and the remain-
ing oxygen with the sulphur unite with the base. In the ac-
tion of a metal on the acid, there is the same result ; only by
the attraction of the metal to oxygen, the whole of that ele-
ment is retained, and the hydrogen is disengaged.

Mauriatic acid gas, then, according to this doctrine, is the
real acid, a ternary compound of a radical (at present un-
known) with oxygen and hydrogen, exactly as sulphuric acid in
its highest state of concentration, is the real acid, a ternary
compound of sulphur, oxygen, and hydrogen. When it is sub-
mitted to an alkaline base, the action exerted causes its decom-
position ; its hydrogen, and part of its oxygen, combine to form
water, and its radical, with its remaining oxygen, unite with
the base, forming a neutral compound, analogous to what
other acids of similar constitution form. When a similar re-
sult is obtained from the action of a metal, its whole oxy-
gen must be considered. as retained, and its hydrogen is libe-
rated.

Nitric acid in its highest state of concentration, is not a de-
finite compound of real acid with about a fourth of its weight
of water; but a ternary compound of nitrogen, oxygen, and
hydrogen. Phosphoric acid is a triple compound of phospho-
rus, oxygen, and hydrogen ; and phosphorous acid is the proper
binary compound of phosphorus and oxygen. The oxalic, tar-
taric, and other vegetable acids, are admitted to be ternary
compounds of carbon, oxygen, and hydrogen, and are there-
fore in strict conformity to the doctrine now illustrated.

A relation of the elements of bodies to acidity is thus dis-
covered, different from what has hitherto been proposed.
When a series of compounds exists, which have certain com-

mon

AND ON SOME SUBJECTS OF CHEMICAL THEORY. $13

mon characteristic properties, and when these compounds all
contain a common element, we conclude with justice, that
these properties: are derived more peculiarly from the action of
this element. On this ground Lavorsrer inferred, by an ample
induction, that oxygen is a principle of acidity. Berrnotuer
brought into view the conclusion, that it is not exclusively so,
from the examples of prussic acid and sulphuretted hydrogen.
In the latter, acidity appeared to be produced by the action of
hydrogen. The discovery by Gay Lussac, of the compound
radical cyanogen, and its.conversion into prussic acid by the addi-
tion of hydrogen, confirmed this conclusion ; and the discovery
of the relations of iodine still farther established it. And now,
if the preceding views are just, the system must be still farther
modified.. While each of these conclusions is just to a certain
extent, each of them requires to be limited in some of the
eases to which they are applied; and. while acidity is. some-
times exclusively connected with oxygen, sometimes with hy-
drogen,, the principle must also be admitted, that it is more
frequently the result of their combined operation..

There appears even: sufficient reason to infer, that from the
united action of these elements, a higher degree of acidity is.
acquired than from the action of either alone. Sulphur affords.
a striking example: of this.. With hydrogen it forms a weak:
acid. With oxygen it also forms an acid, which, though of su-
_ perior energy, still does not display much power. With hy-
drogen and oxygen it seems to receive the acidifying influence:
of both, and its acidity is proportionally exalted.

Nitrogen with hydrogen forms a compound altogether desti-
tute of acidity, and possessed even of qualities’ the reverse.
With oxygen in two definite proportions, it forms oxides;
and it is doubtful, if in any proportion, it can establish with
oxygen an insulated acid.. But with oxygen and hydrogen in

Vou. VIII. P: IL Rr ~~ union

314 OBSERVATIONS ON MURIATIC ACID,

union it forms nitric acid, a compound more permanent, and
of energetic action.

Carbon with hydrogen forms compounds which retain in-
flammability without any acid quality; with oxygen it forms
first an inflammable oxide, and with a larger proportion a weak
acid. But, combined with both hydrogen and oxygen, in dif-
ferent proportions, it forms in the vegetable acids compounds
having a high acidity. These acids, therefore, are not to be re-
garded, according to the theory of Lavoisizr, as composed of a
compound base of carbon and hydrogen, acidified by oxygen,
but of a simple base, carbon, acidified by the joint action of
oxygen and hydrogen.

Mnuriatic acid itself presents the same result. Oxymuriatic:
acid must be considered, according to this doctrine, as a com-
pound of an unknown radical, (Murion, if the term may be al-
lowed), with oxygen, analogous in this respect to sulphurous
acid, except that in the latter there is an excess of base, in the
former an excess of oxygen: And oxymuriatic acid, with the
addition of hydrogen, forms the ternary compound muriatic
acid, as sulphurous acid with the same addition forms hydro-
sulphuric acid, with a deposition of the excess of sulphur. There
is, accordingly, the strictest analogy between muriatic acid and
those other acids, the sulphuric, nitric, &c. which contain both
oxygen and hydrogen; while there is none, as Berzetius re-
marked, between it and those, such as the prussic acid or sul-
phuretted hydrogen, which contain merely hydrogen. This prin-
ciple solves the difficulty which has always presented itself in
the relation of muriatic and oxymuriatic acids on LavoisrEr’s
theory of acidity,—that the latter, though it has received an
addition of oxygen, is inferior in acid power to the former.
It is so precisely as the binary sulphurous acid is one of less
energy of action than the ternary hydro-sulphuric acid, or as
the carbonic is less powerful than the oxalic acid. The pro-

per

AND ON SOME SUBJECTS OF CHEMICAL THEORY. 315

per analogy is that of the oxymuriatic with the sulphurous
acid, and the muriatic with the sulphuric ; and under this point
of view there is no anomaly, but strict conformity. And thus
also is accounted for, what is at variance with the hypothesis
of Gay Lussac, the total want of analogy between chlorine and
sulphur, which he classes together, except in the single cir-
cumstance of acidity being communicated to both by hydro-
gen; while there exists a close analogy between sulphurous
acid and oxymuriatic acid, in their most essential properties,—
their gaseous form, their specific gravity, their suffocating
odour, their power of destroying vegetable colours, their solu-
bility in water; their remaining combined with it in congela-
tion ; their acidity, their combining weights, and their being
attracted to the positive pole of the voltaic series ; and any de-
viation from this analogy evidently arises from the excess of
oxyen in oxymuriatic acid *.

It is obvious, that it would be in vain to seek for the disco-
very of real muriatic acid in its insulated form. It exists no
more than real sulphuric or real nitric acid. The oxygen and
sulphur, or oxygen and nitrogen in union with a salifiable base
in the sulphates and nitrates, may not be in direct combina-

Rr2 tion,

* It is curious with regard to the most important of these analogies, that of
the equivalent or combining weights, that oxymuriatic acid stands next to sul-
phurous acid; the former in Dr Wottasron’s scale being 44, while the latter
will be found to he 40. The acidity of oxymuriatic acid is fully established by
the most unequivocal acid property, that of combining with alkalis, and forming
neutral compounds. The saline nature of these compounds had been shewn by
Bertuoittet; that with lime has been demonstrated by Mr Daxton, who also
pointed out the probability from the results, by double decomposition, that the
acid combines in a similar manner with other salifiable bases; and the existence
of these compounds has been established by Mr Witson.

316 OBSERVATIONS ON MURIATIC ACID,

tion, nor capable of existing as a separate binary compound.
The insulated binary compound of the radical of muriatic acid
with oxygen is oxymuriatic acid, as the binary compound of
sulphur and oxygen is sulphurous acid, and of nitrogen and
oxygen, nitrous and nitric oxides,

Iodine, the discovery of which and its relations, is for a
time given predominance to the new doctrine of chlorine, con-
forms sufficiently to these views. Some have considered it as
a body belonging to the same class as chlorine ; others regard
it as more seaippond to sulphur. It has little analogy to
either, except in stad property of forming acids with oxygen |
and with hydrogen. It differs remarkably from chlorine in its
comparative inertness, its solidity, specific gravity, and great
weight of its equivalent quantity. And it differs from sulphur
in its want of inflammability, its solubility in water, and its be-
ing attracted to the positive pole of the voltaic series. All
these analogies are preserved, and its relations connected, by
considering it as an oxide, which, both from its specific gravity,
the colour of its compounds, and the great weight of its equi-.
valent quantity, has probably a metallic base ; and which ac~
quires acidity by an addition of hydrogen on the one hand,
and on the other by the addition of oxygen, or of oxygen and
hydrogen. In these respects, and in many of its chemical pro-
perties and relations, a considerable analogy exists between it
and oxide of arsenic or oxide of tellurium. Or if it were to be
classed as a simple substance, (on the ground of its not having
been decomposed,)—which forms an acid with hydrogen,
and another with oxygen and hydrogen; it does not in these
respects offer any deviation compared with other acidifiable
bases, or afford an argument of much weight in support of the
undecomposed nature of chlorine.

The

AND ON SOME SUBJECTS OF CHEMICAL THEORY. 3lT

The doctrine I have illustrated, affords a satisfactory expla-
nation of the properties of the compounds fermed by oxymu-
riatic acid with certain inflammables, particularly with sulphur
and phosphorus. These undoubtedly present an anomaly in
the other views that have been given ef their constitution. In
the old doctrine, they are considered as compounds ef two real
acids ;—one of muriatic, with phosphorous or phosphoric acid ;
the other of muriatic, with sulphurous or sulphuric acid. But
they have none of the properties which would be looked for in
such a combination; they have no acidity, or if any appear in
one of the compounds with phosphorus, it is to a very limited
and doubtful extent ; and they are substances even which have
little energy of chemical action. In the. new doctrine they are
cable as compounds of chlorine with their bases, sulphur
and phosphorus. Of course, as these bases form powerful acids
with oxygen, and as chlorine is considered as an element of
similar agency as oxygen, communicating similar powers, and
conferring acidity even on hydrogen, they might, with not less
reason than on the other doctrine, be expected to be acids of
the greatest strength. The view I have stated accounts for their
characters. They are ternary compounds, of the radical of mu-
riatic acid with the particular inflammable,—sulphur, or phos-
phorus, with oxygen. The oxygen is not in sufficient quantity
to communicate acidity, or, in one of the combinations of phos-
phorus, does so only to a very slight extent. But when water
is added, a sufficient proportion of oxygen is supplied to pro-
duce this result, and the acidity is exalted by the correspond-
‘ing hydrogen entering into the combination. ' What has been
called Phosgene Gas, procured under certain circumstances
from the action of oxymuriatic gas and carbonic oxide, may
be regarded as of a similar nature, the agency of a small por-
tion of w water or of hydrogen being probably essential to its for-
. mation,

318 OBSERVATIONS ON. MURIATIC ACID,

mation, a circumstance which serves to account for the discor-
dant results with regard to its production *.

It deserves remark, that while there runs through the whole
series of acidifiable bases in relation to their combinations with
oxygen and hydrogen, a general analogy, there is also some
deviation, and something with regard to each that is specific.
Sulphur affords the most perfect example of their agency. It
forms an acid with hydrogen ; it forms another with oxygen ;
and a third, still more powerful, from the joint action of oxy-
gen and hydrogen. Carbon forms an acid with oxygen ; it also
forms a series of acids of greater strength with oxygen and hy-
drogen ; it acquires no acidity, however, from hydrogen alone ;
and with an inferior proportion of oxygen it forms an oxide.
Phosphorus bears a strict analogy to sulphur, except that its
combination with hydrogen does not give rise to acidity, a cir-
cumstance in which it resembles carbon. Nitrogen is peculiar
in forming two oxides with different definite proportions of
oxygen; it is doubtful if it forms a free acid with oxygen
alone ; but it conforms to the general law, and forms a powerful
acid with oxygen and hydrogen. Assuming the existence of a
simple radical of muriatic acid, it resembles sulphur, phospho-
rus and carbon, in forming an acid with oxygen, and one still

more

* The difficulty of entirely excluding water and hydrogen from the consti-
tuents of this gas is sufficiently apparent. And the fact, that it cannot be form-
ed from them by the action of the electric spark, but only by the continued ac-
tion of solar light, is favourable to the above opinion. ‘The conversion of car-
bonic oxide into carbonic acid, by the joint action of oxymuriatic gas and hydro-
gen, an experiment which I performed when the new hypothesis with regard to
the nature of chlorine was brought forward, and which. was attempted to be in~

validated by some singular controversial methods, I consider as depending pro-

bably on the same principle.

a cored,
ee

Pe cts

AND ON SOME SUBJECTS OF CHEMICAL THEORY. 319

more powerful with oxygen and hydrogen ; but it differs in the
peculiarity, that. the proportion of oxygen to the base in the
binary combination is considerably larger than in the ternary,
so that the addition of hydrogen converts the one into the
other; and also in its combining apparently with more nume-
rous proportions of oxygen than any of the other acidifiable
bases,—two circumstances which, as well as the difficulty of
effecting its decomposition, probably depend on the same
cause, the strength of its attraction to oxygen. The fluoric are
similar to the muriatic compounds, except that the binary com-
pound of the radical with oxygen cannot be obtained in an in-
sulated form, and that its combinations with oxygen are less
numerous. ‘The relations of iodine or its radical are similar to
those of the radical of muriatic acid, or perhaps rather to sul-
phur, except that its binary compound with oxygen does not
appear to have acidity, in which it approaches to the metals.
The metals usually combine with oxygen so as to form oxides}
some of them also form acids with oxygen, or with oxygen and

hydrogen ; and these last usually also combine with hydrogen

alone. This fact, of some of the metals forming acids, is so far
an anomaly, since their compounds with oxygen rather form
alkalis, and no other substances give rise to both results; the
greater number of the substances, too, which form saad with
oxygen or hydrogen, are evidently, from the smallness of their
combining quantities, not of a metallic nature. Still the con-
nection between the two classes is in some measure establish-
ed on the one hand, by nitrogen, which with hydrogen forms
an alkali, and on the other by iodine, which has properties and
relations common to both.

In some cases it is probable, that there is a variation in the
proportions of these ternary combinations, giving rise to a di-

versity of products, which exist only in combination with those _
bodies

320 OBSERVATIONS ON MURIATIC ACID,

bodies by which their formation is determined, and, being mo-
dified by any process causing their evolution, are not easily ob-
served. It is doubtful if the same base in any case forms dif-
ferent acids by combination with oxygen in different propor-
tions, or by combination with hydrogen in different propor-
tions. But the example of the vegetable acids seems to shew
that this may occur in the united action of oxygen and hydro-
gen; carbon acidified by different proportions of ‘these ele-
ments, constituting the composition of these acids. Other ba-
ses may present similar results. The radical of muriatic acid
may unite with other proportions of oxygen and hydrogen than
those which form muriatic acid; and this might afford a solu-
tion of the theoretical difficulty of the production of water in
the experiments in the first part of this memoir, independent
of the explanation of it from the formation of a super-muriate.
A compound may be formed with less oxygen and hydrogen
than what exist in muriatic acid, in combination with the me-
tal acted on, and thus a portion of water may be liberated.
Nor will it be easy to establish this by any difference in the
product, as it can scarcely be submitted to any examination,
but by processes which change the result. The chloric acid
which, according to Gay Lussac, cannot exist insulated with-
out water, may be in like manner a ternary compound of these
elements in other proportions. Prosecuting the same analogy,
the glacial or fuming oil of vitriol may be, not what has lately
been asserted, real sulphuric acid, (for probably no such sub-
stance as that to which this term has been applied, can be ob-
tained insulated), but a compound of sulphur with oxygen and
hydrogen, in proportions different from those which constitute
common oil of vitriol. Nitrous acid, if it cannot be formed
without water, may be a compound of nitrogen with a smaller

proportion

— or

AND ON SOME SUBJECTS OF CHEMICAL THEORY. 321

proportion of oxygen and hydrogen, than nitric acid. And
some of the acids lately described, of which phosphorus is
the base, may arise from variations of proportions of this_
kind.

The view which I have now illustrated, I must add, is not to
be regarded as mere speculation. The evidence in support of
it, is just as conclusive as that from which the opposite opinion
is inferred. The obtaining water from a compound is no ne-
cessary proof that water pre-existed in it; and conversely, the
causing water to enter into combination in a compound, is no
necessary proof that it remains in the state of water in the
product. In many cases we draw the reverse conclusions, con-
sidering water as being formed where it is obtained, and as de-
composed where it is communicated. And in the case of its re-
lation to acids, it will be found that there is no strict evidence
of its existing as water in combination with what is considered
as the real acid; and of course the conclusion is equally open
to be drawn, that it exists in these combinations in the state
of its elements, and that when obtained, it is a product of a
change of composition.

It is even more probable, a priori, that the ultimate elements
should act on each other where energetic affinities are evident-
ly exerted, than the immediate principles, and the relations of
these elements will determine the combinations, and the pro-
portions. And by admitting this view, we avoid the anomaly
which is presented in ascribing to the agency of water effects
so different from those to which it usually gives rise. In ge-
neral, water operates on bodies simply as a solvent, overcoming
cohesion in solids, diluting liquids, or absorbing gases, without
otherwise modifying their properties, or communicating to
them any important chemical powers. But in the particular
cases now referred to, it is supposed to produce the effects of

Vou. VILL P. II. Ss. the

322 OBSERVATIONS ON MURIATIC ACID;

the most energetic chemical agent ; it enters into combination
in proportions strictly definite, is retained by the most power-
ful affinities; communicates new and characteristic properties ;
and is essential even to the existence of these compounds, in
an insulated form. Berzextius and Gay Lussac have stated,
that it is to be considered as a base necessary to retain the ele-
ments of the acid combined, though without neutralising the
acid properties,—an opinion which in itself, and still more with
this condition, is certainly sufficiently incongruous. And both
theories admit equally of incongruity in the supposed presence
and energetic action of water in acids. The old doctrine ad-
mits its influence in sulphuric, nitric, phosphoric, and muriatic
acids, though at variance with its principle, that oxygen is the
element which confers acidity, or at least having no conformi-
ty to that principle, nor receiving explanation from it. The
new doctrine refuses to admit it with regard to muriatic acid,
but admits it in all the others,—an exception which serves only
to render the system more objectionable by the violation of
analogy; while the admission with regard to the others is
equally incapable of being accounted for on any principle it af-
fords. By considering oxygen and hydrogen as elements
conferring acidity, a satisfactory solution is afforded of the ef-
fects produced in these cases by their joint operation; and in-
dependent of this, it is much more probable, a@ priori, that such
effects should arise from the action of elements so powerful,
than from the agency of water, which, in its general relations,
exerts such feeble powers. Lastly, The principle on which the
presence of combined water in these acids has been supposed.
to depend, —that of the strong attraction of the acid to water,
seems altogether fallacious; for on this principle sulphurous
acid should also contain combined water, and sulphuretted hy-
drogen, and even carbonic acid, might be expected to retain a

small .

oer Re

AND ON SOME SUBJECTS OF CHEMICAL THEORY. 323

small portion. The whole evidently depends on difference of
constitution. Sulphurous acid, sulphuretted hydrogen, and
carbonic acid, are binary compounds, and therefore yield no
water, nor retain any in intimate combination; and in the
others, the proportion of water supposed to exist will be found
to have no relation to the attraction of the acid to water, so far
as this can be inferred, as is evident from the example of phos-
phoric acid affording as much as sulphuric or nitric ; but to the
relations of its elements, and more particularly of its oxygen,
to the radical. This last fact affords nearly a demonstration, that
the constitution is that of simultaneous combination of the ele-
ments, and not that of water and acid.

That water may also exist in immediate combination with
acids, without being resolved into its elements, is sufficiently
possible; and it probably is in this state, in those cases, in
which there are no indications of an intimate combination, or
definite proportion. It may then be considered as in solution
similar to that in which it holds salts dissolved, or, what is a
closer analogy, similar to that in which it holds dissolved the
vegetable acids, which are admitted to be ternary compounds

-of carbon, hydrogen, and oxygen. The opposite view applies

only to that portion of water considered as essential to the
body in an insulated state, and in which it is combined in a de-
finite proportion, observing in its relations, or the relations of
its elements, equivalent proportions to other bodies.
In the last place, Considering this opinion in relation to the

_ two opposite views which have been maintained with regard to

the constitution of oxymuriatic and muriatic acids, while it has
all the evidence in its favour from which the existence of wa-
ter in muriatic acid gas is inferred, and all the analogies by
which this is confirmed ; it has the support which the doctrine
of the undecompounded nature of chlorine derives from the re-

Ss2 lations

324 OBSERVATIONS ON MURIATIC ACID,

lations of sulphur, iodine, and cyanogen; and from the indue-
tion that hydrogen, as well as oxygen, communicates acidity.
It avoids, at the same time, the improbability which attends
that doctrine, in its leading principle, that muriatic acid con-
tains no combined water, though other powerful acids are held
to contain it, and though it affords water by the very same pro-
cesses by which they yield it; and in the still greater violation
of analogy, (the most extraordinary perhaps ever admitted in
chemical reasoning), involved in the conclusion, that the com-
pounds which this acid forms with salifiable bases, though the
same in all generic properties with those formed by other acids,
are not of similar constitution, and are not even ofa saline nature.
It unites the advantages, therefore, of both doctrines, and con-
nects under one system facts which are otherwise insulated,
and partial generalisations, which, instead of having any rela-
tion, seem opposed to each other.

The same general view, I have still to add, may be farther
extended. Alkalinity, as well as acidity, is the result appa-
rently of the action of oxygen; the fixed alkalis, the earths,
and the metallic oxides, which all contain it as a common ele-
ment, forming a series in which it is difficult to draw any well
defined line of distinction. Ammonia alone remains an excep-
tion: it contains no-oxygen, and yet possesses in a very mark-
ed degree all the alkaline properties,—an anomaly so great, as
to have led almost every chemist to infer that oxygen must ex-
ist as an element in one or other of its constituent principles ;
and as nitrogen is the one apparently least elementary, it has
been supposed to be a compound containing oxygen. ‘The re-
sult may be accounted for, however, on a very different prin-
ciple. As hydrogen, in some cases, give rise, as well as oxy-
gen does, to acidity, so it may in other cases give rise to alka-
linity. Under this point of view, ammonia is a compound of

which

ee

q
J
y
:
:

wie

AND ON SOME SUBJECTS OF CHEMICAL THEORY. $825

which nitrogen is the base, deriving its alkaline power from
hydrogen ; it stands, therefore, in the same relation to the other

alkalis, that sulphuretted hydrogen does to the acids. And

thus the whole speculation with regard to the imaginary me-
tallic base Ammonium, and the existence of oxygen in ammo-
nia, and in nitrogen, falls to the ground, while the anomaly pre-
sented by this alkali is removed. If the claim of the lately
discovered principle in opium, Morphia as it has been named,
to the distinction of an alkali be established, as from its origin
it must probably have a compound base, it may, if it contain

hydrogen, bear the same relation to the other alkalis, that prus-

sic acid does to the acids; or if it contain oxygen, it will be
analogous to the vegetable acids.

The fixed alkalis, and the alkaline earths, are considered as
containing water in intimate combination, in a definite propor-
tion ; and it is doubtful if they can be obtained free from it in an

_ insulated state, retaining at the same time their alkaline pro-

perties. It is obvious, however, that the elements of water
may exist in combination with the base: that potash, for ex-
ample, is not a compound of an oxide of potassium with water,
but of potassium, oxygen and hydrogen. Hence when, on add-
ing water to peroxide of potassium, potash is produced, and
oxyen gas is disengaged ; this is not owing, as has been suppo-
sed, to the excess of oxygen in the peroxide being expelled,
and the water taking its place; but to the water being decom-
posed, and a portion of its hydrogen entering into the combi-
nation; to form the alkali, while the corresponding oxygen is
liberated. If hydrogen were brought to act on peroxide of
potassium, the alkali would in like manner be formed. With

.the peroxide of barium, this very change, from the action of hy-
_ drogen, takes place ; the hydrogen, according to the usual ex-

planation, combining with its oxygen, and forming water, which
unites

326 OBSERVATIONS ON MURIATIC ACID,

unites with the real earth, forming the hydrate ;—in other
words, and according to the strict expression of the fact, the
hydrogen entering into the composition, and forming the ba-
rytes ;—a result perfectly analogous to the formation of muri-
atic acid from oxymuriatic gas by the agency of hydrogen.

The evidence in support of this doctrine, it is evident, is of
the same kind as that with regard to the doctrine applied to
the acids. There is the same superior probability in favour of
the conclusion, that the elements of water, rather than water
itself, exist in these compounds, from the consideration, that
modifications of properties so important, are more likely to
arise from the agency of these elements, than from any action
which water can exert. And that water does not exist in them,
in consequence of the strength of attraction which the real al-
kali, as it has been considered, exerts towards it, is evident
from this, that on the same principle ammonia ought to con-
tain combined water in its insulated form, which is not the
case. The combination of water, therefore, or rather of its
principles, in these compounds, depends on relations subsist-
ing among the ultimate elements, not on an affinity exerted by
the alkali itself; and this adds confirmation to the conclusion,
that these elements are in ternary union.

Their superior alkaline energy, compared with the common
metallic oxides, may obviously arise from the joint action of
the hydrogen and oxygen, in the same manner that the acidity
of the ternary, compared with the binary acils, is increased by
a similar constitution. Thus the class of alkalis will exhibit
the same relations as the class of acids. Some are compounds
of a base with oxygen: such are the greater number of the me-
tallic oxides, and several, probably, of the earths. Ammonia is
a compound of a base with hydrogen. Potash, soda, barytes,
strontites, and, probably, lime, are compounds of bases with

oxygen

AND ON SOME SUBJECTS OF CHEMICAL THEORY. 327

oxygen and hydrogen ; and these last, like the analogous order
among the acids possess the highest power. Many of the me-
tallic oxides, however, in the state in which they combine with
the greatest facility with the acids, are hydrates,—that is, sup-
posed compounds of the oxide with water, but probably ter-
nary compounds of the metal with oxygen and hydrogen; and
their facility of combination, may depend on this constitution.
The same principle explains the necessity, not otherwise easi-
ly accounted for, of the presence of water, to enable some of
the earths, as barytes, to combine with acids.

There are two views under which the neutral’ salts may be
considered in the preceding theory. It has been shown, that
when water is obtained in the action of a salifiable base, whe-
ther alkali, earth, or metallic oxide, there is reason to infer that
this water is formed by the hydrogen and part of the oxygen
of the acid entering into binary combinations ; and when water
is obtained from an alkali by the action of an acid, there is the
same reason to believe, that it is formed by the combination of
the hydrogen of the alkali with a portion of its oxygen. In
these cases it may be supposed, that the radical of the acid
combines with its remaining oxygen, forming a binary com-
pound, which may still be considered as an acid; and that the
radical of the alkali combines with its remaining oxygen, form-
ing a binary compound, which may be regarded as an alkali;
and these two compounds may unite with each other, forming
the neutral salt. This is conformable nearly to the common
doctrine. But there is another point of view under which the
subject may also be considered. A ternary combination, into
which oxygen and hydrogen enter, gives rise apparently to a
higher state of acidity, and to a greater degree of alkaline ener-
gy than is acquired from a mere binary combination into which
‘oxygen enters. It is doubtful, therefore, if such binary com-

pounds

328 OBSERVATIONS ON MURIATIC ACID, &c.

pounds were formed, if they would constitute either acid or al-
kali. And there is at least no proof of their formation. In all
these cases, while the hydrogen present combines with the re-
quisite proportion of oxygen forming water, the radical of the
acid, and the radical of the base, may enter into union with
the remaining oxygen, and form a ternary compound. And
where hydrogen is not present, such a combination may be at
once established.

It is not easy to determine which of these opinions is just.
The reason above stated, renders the latter, perhaps, more pro-
bable ; and the view which leads to the conclusion, that in the
constitution of the acids and alkalis, the three elements, when
present, are in simultaneous combination, leads also to a
similar conclusion with regard to the constitution of the neu-
tral salts. If this be adopted, neutralisation is not the satura-
tion of acid with alkali, and the subversion of the properties of
the one by the opposed action of those of the other ; but is the
change of composition of both, and the quiescence of the ele-
ments, in that proportion in which their affinities are in a state
of equilibrium without any excess. The compounds, therefore,
have little activity ; and energy of action is restored only by
the reproduction of substances, which, by their mutual attrac-
tions, tend to the same state of quiescence.

All these results display more fully the extensive relations
of the two elements, oxygen and hydrogen. They do not act
merely in opposition, as had been imagined, but more fre-
quently in union, producing similar effects. Hydrogen is of
nearly equal importance with Oxygen, and the principal details
of chemistry, consist in their modified action on inflammable
and metallic bodies.

XVII.

SS

XVII. Experiments on the Relation between Muriatic Acid and
Chlorine ; to which is subjoined the Description of a
New Instrument, for the Analysis of Gases by Explo-
sion. By ANprew Ure, M. D. Professor of the An-
dersonian Institution, and Member of the Geological
Society.

(Read Nov. 17. 1817.)

PART IL.

ia Chloridic Theory, though more limited in its application
to chemical phenomena, than the Antiphlogistic, may justly
be regarded as of scarcely inferior importance. If established,
it leads to the adoption of entirely new views concerning com-

- bustion and many of its. products ; it removes the muriates, a
set. of apparently well characterised saline bodies, from the
class of salts altogether ; and it has given birth, by analogy, to
two new genera of compounds, in which iodine and fluorine,
like chlorine, act a corresponding part with. oxygen, in the sys-
tem of Lavoisier.

This new era in chemical’ science, unquestionably origina=
ted from the masterly researches of Sir Humpury Davy on
Oxymuriatie Acid Gas; a substance which, after resisting the
most powerful means of decomposition which his sagacity could
invent, or his ingenuity apply, he declared to be, according to
the true logic of chemistry, an elementary body, and not a

Vou. VIII. P. ID. Te compound.

830 EXPERIMENTS ON THE RELATION

compound of muriatic acid and oxygen, as was previously ima-
gined, and as its name seemed to denote. He accordingly as-
signed to it the term Chlorine, descriptive of its colour ; a name
now generally used.

Chlorine when combined with an equal volume of hydrogen,
forms Muriatic Acid Gas, the Hydrochloric of Gay Lussac.
This muriatic acid gas, hygrometrically dry, unites with its own
bulk of dry ammoniacal gas, to constitute the dry pulverulent
solid called Sal Ammoniac. Hence this saline body is ulti-
mately composed of chlorine and hydrogen, for its acid; and
of azote and hydrogen, for its base. By comparing the weights
of muriatic acid and ammoniacal gases, in equal volumes, we
obtain the proportion of 67.8 muriatic acid gas, to 32.2 ammo-
nia, for the composition of 100 parts by weight of the solid
salt. If we saturate liquid muriatic acid with gaseous ammo-
nia, or with the base of the ammoniacal carbonate, and evapo-
rate carefully to dryness, we find the resulting salt to have pre-
cisely the same constitution, namely, in 100 parts, 51 of dry
muriatic acid, equivalent to 67.8 of the acid gas, and the re-
mainder 32.2 ammonia. This concurrence of results, whatever
way the salt may be obtained, is fully demonstrated in my re-
searches on the ammoniacal salts, (Annals of Philosophy for
September 1817), and proves it to be a substance of very uni-
form and determinate composition.

Those chemists who consider chlorine to be oxymuriatic
acid, must suppose, when a volume of it weighing 44.13 unites
with an equal volume of hydrogen, weighing 1.32, that, in the
resulting hydrochloric or muriatic acid gas = 45.45, this hy-
drogen exists combined with 10.00 of oxygen, its saturating
quantity, forming 11.32 of constituent water. In this view,
uriatic acid gas, like gaseous, sulphuric, and nitric acids, con-
tains water as an essential element. There seems to be no

violation

BETWEEN MURIATIC ACID AND CHLORINE. 331

violation of chemical analogy in this supposition. The quan-
a oa! ¢ . 11.32 :
tity will be represented by the fraction sins being nearly one-

fourth.

If chlorine, however, be a simple body, which forms with
hydrogen, muriatic acid gas, then sal ammoniac is rightly na-
med Hydrochlorate of Ammonia. And since ammonia itself
results from three volumes of hydrogen and one of azote, con-
densed into two volumes, that saline body can contain neither
water, nor its indispensable element oxygen.

On the other hand, if chlorine be oxymuriatic acid, then the
fourth part of water existing in the resulting muriatic acid gas,
must necessarily enter into the sal ammoniac as an essential
constituent ; for the whole ponderable matter of that gas, as
well as of the ammonia, passes into the salt. This water being
as indispensable an ingredient of sal ammoniac as it is of oil of
vitriol ; heat alone can no more separate it from the former,.
than it can from the latter compound.

Moreover, if we decompose sal ammoniac by the agency of
any body containing oxygen, an evident source of fallacy exists
relative to the watery product, which may be referred by the
supporters of the chloridic theory, not to the salt itself, but to
the hydrogen of the hydrochloric acid, united with the oxygen
of the decomposing substance. This ambiguous interpretation,
is experimentally illustrated, in my paper on the Ammoniacal
Salts.

If, however, we shall decompose that. equivocal salt, by means
of a substance, which certainly contains no oxygen; and if we

still obtain water in nearly the above proportions, then this re-

sult is no longer equivocal, nor will it admit of two interpreta-
tions. We must thenceforth be: compelled to recognise in mu-

‘ viatic acid gas, as in the other acid vapours, waTer as an ingre-

ite 2 dient

$382 EXPERIMENTS ON THE RELATION

dient essential to its constitution ; and to acknowledge that
chlorine consists of a base united to oxygen, or is in fact oxy-
genated muriatic acid, as Lavoisier and Bertuo.zer taught, and
as the whole chemical world believed, till their faith was late-
ly shaken or subverted, by the predominating genius of Sir
Humpury Davy.

With the view of deciding the above important controversy,
I performed the following experiments.

Of sal ammoniac, kept for some time in a platina capsule at
a subliming heat, to remove every particle of adhering mois-
ture, a known quantity was put into a glass tube, and made to
slide down to the one end, which had been hermetically sealed.
Over it a given weight of bright metallic lamine, cut into slen-
der segments, was lightly pressed. The salt occupied in gene-
ral about one inch of the tube; the Jamine four or five inches.
Silver, copper, and turnings of iron made with a dry tool, were
employed in successive experiments. The open extremity of
the tube was drawn out to a point, and recurved, so as to pass
under a vessel inverted on the mercurial pneumatic trough.
Between this and the portion containing the metal, there was
a length of six or more inches of tube, which was kept cool.
In one variation of the experiment, a tube of Reaumur’s por-
celain was used for containing the materials, to which was
firmly luted by a collar of caoutchouc, a glass tube, with a
little globe blown in its middle, and its loose end plunged, as
usual, into the mercurial trough. .

When tubes of crystal glass were employed, the part con-
taining the materials was lodged in a semicylindrical case of
iron, which traversed a small charcoal furnace, five or six
inches in diameter. The metallic laminz being raised to full
ignition in day-light, the case and tube were slightly moved

forward,

BETWEEN MURIATIC ACID AND CHLORINE. $33

forward, in order to bring a little of the salt within the sphere
of the heat. Great nicety was required in the advancement of
the sealed extremity ; for the glass tube being perfectly soften-
ed in its middle, too sudden volatilisation of the salt never
failed, by inflating and bursting it, to spoil the experiment.

- This accident frequently happened. On the other hand, if the
central part of the tube was exposed to merely a dull red, the
experiment would not succeed with silver and copper. At
this temperature they did not decompose the sal ammoniac.
When, however, the above-mentioned precautions were obser-
ved, dew could be perceived to settle speedily on the cool por-
tion of the tube. This dew became more and more visible as
the sublimation advanced, till, finally collecting into distinct
drops, it trickled down the sides in strize, and formed a fila-
ment along the bottom. ‘To obtain good results of this kind,
four or five hours must be devoted to one experiment, in
which 20 grains of salt, and from 60 to 100 of metal, are em-
ployed. More rapid transmission of the salts effects mere sub-
limation. Bubbles of gas come over, which, with silver and
copper laminz, are found to be a mixture of ammonia and hy-
drogen. In this case, the liquid condensed, is water of ammo-
nia.

The metallic laminz are evidently heavier than before their
introduction ; but the increase of their weight could not be ex-
actly ascertained, because a portion of the silver or copper is
impressed on the inner surface of the tube, giving it a very
beautiful iridescent and metallic lustre, similar to the colours
of the diamond beetle, viewed in a microscope. The silver la-
minz, have for the most part exchanged their native brilliant
white, for a dull-brown or greyish hue}; and instead of being
eminently tough and ductile, have become more brittle than
any substance with which I am acquainted. The slightest

touch

334 EXPERIMENTS ON THE RELATION

touch of the finger breaks them across. Digested in pure ni-
tric acid somewhat dilute, the segments only partially dissolve,
bits of muriate of silver, of their own shape, being left in the
liquid. .

The ignited copper turnings, after experiencing the action of
sal ammoniac, are found to have lost also their original lustre,
and have acquired a dull brown colour. Digested in water, a
liquid muriate is obtained, which gives the characteristic brown
precipitate with prussiate of potash.

The most considerable of my experiments with turnings was
made with the tube of Reaumur’s porcelain, which, as it con-
tains no oxide of lead, is not liable to any ambiguity on this.
score, and being capable of sustaining a very high heat with-
out fusion, permitted me to obtain very satisfactory results in-
deed.

Thirty grains of recently heated sal ammoniac being put
down to the sealed end, 200 grains of bright turnings of very
pure soft iron were introduced over it, so as to occupy six
inches of the tube. The glass tube above described, was at-
tached by the elastic gum collar. The part holding the iron
being brought to bright ignition, the sealed end of the tube
was advanced by degrees almost imperceptible. As soon as
the salt began to exhale, moisture began to condense in the
glass tube, though none ever appeared prior to heating the sal
ammoniac. The evolution of gas was much more copious:
than in any of the experiments with the other metals. When
allowed to escape through the quicksilver into the air, it exhi-
bited the dense cloud, and had the odour of muriatic acid.
Received into a tube over mercury, and then exposed to the
action of water, ;4, parts of the volume were absorbed, which
on trial were found to be pure muriatic acid. The remainder
was a mixture of azote and hydrogen, in the proportions very

nearly

Bid
ve

BETWEEN MURIATIC ACID AND CHLORINE. 335

nearly that are known to constitute ammonia, I analysed this
mixed gas, by explosion with half its volume of pure oxygen,
in a peculiar apparatus, which I shall describe in the sequel.
On firing 100 measures with the electric spark, ‘76.2 disappear-
ed, 2 of which, = 50.8, are hydrogen. Before explosion, the
hundred volumes consisted of 662 ammoniacal gaseous matter,
+ 331 oxygen. Of these 662 parts, 50.8, are hydrogen, and
15.86 azote ; or in the 100, 76.2 4+ 23.8. But, by Gay Lus-
sac, 1 volume of azote unites with 3 volumes of hydrogen to
form ammonia. Hence 23.8 measures of azote should have
been accompanied with only 71.4 of hydrogen, instead of 76.2
actually obtained. This excess of hydrogen is due to the de-
composition of a little of the watery product, in the formation
of the muriate of iron. That muriate of iron is formed, is pro-
ved by many circumstances. First, the disappearance of the
acid in the gaseous products. Sal ammoniac being decompo-
sed with its ultimate gases, will consist of two measures of
those constituting the alkali + one measure of the muriatic.
Hence 100 volumes should contain 333 of this acid gas; but
they actually contained only about 5. Therefore about 28
measures, which form the difference, were condensed with the
iron. Secondly, the iron turnings had increased in weight ;
they deliquesced speedily on exposure to the atmosphere, and,
digested in water, they yielded an acerb-tasted solution of mu-
riate of iron, giving with prussiate of potash a copious blue |
precipitate.

The quantity of muriate produced in the experiment, will
depend on the proportion of turnings which have been but
moderately heated; for the ammonia, in its passage over the
strongly ignited iron, may be conceived to separate the oxy-
gen, and thus prevent the formation of muriate.

Water

336: EXPERIMENTS ON THE RELATION

Water impregnated with muriatic acid equal in weight to
nearly one-sixth of the sal ammoniac decomposed, is uniform-
ly obtained by the above process. Scarcely a particle of am-
monia seems to escape entire decomposition. The evolved
muriatic acid, amounting to -£,; of the whole gaseous products,
must carry off with it a portion of its constituent water.
Hence we ought to find a little less water here condensed,
than, by my experiments on the ammoniacal salts above refer-
red to, sal ammoniac, viewed as a muriate, is shewn to con-
tain.

It seems evidently to follow, from this experimental detail,
that chlorine is oxygenated muriatic acid. Since dry sal am-
moniac consists of ammonia and muriatic acid gases, both hy-.
grometrically dry ; and since water is obtained in its decompo-
sition by pure metals; this water must have existed in the ga-
seous acid ; for all experiments concur.in proving ammonia it-.
self to contain nothing but azote and hydrogen. And, finally,
since muriatic acid gas is a compound of chlorine and hydro-
gen, the water derived from the resulting muriatic acid, de-
monstrates the presence of oxygen in the chlorine, or, in other
words, that it is really oxymuriatic acid *.

All the experimental phenomena hitherto adduced in the
ehloridic controversy, were susceptible of explanation on both
the old and new doctrine. Thus, the hydrogen which remains
after tin is subjected at a high temperature to muriatic acid

gas,,

* If the Chloridic Theory be still retained, then the production of water in
the above circumstances can be ascribed only to the decomposition of azote into
oxygen and hydrogen, as has been already indicated in my paper on the Ammo-
niacal Salts. It is possible that this alternative may eventually be found the true
one; yet in the present state of our knowledge, such an inference would be il-
logical.

cade S ee

BETWEEN MURIATIC ACID AND CHLORINE. 337

gas, could be regarded with Davy, as resulting from a metallic
analysis of hydrochloric acid ; or it might be derived from the

_combined water of muriatic acid, of which the oxygen became

fixed in the muriate of tin. When chlorine also at high heats
was made to act on earths or common metallic oxides, the
evolved oxygen, could be referred with equal probability either
to the solid or to the gas.

And though we ignite by the strongest voltaic power, char-
coal or other combustibles in chlorine, still we shall not be
able to convert it into muriatic acid gas, for want of the essen-
tial constituent water ; no more than we can, without the same
water, obtain oil of vitriol. Present water to chlorine, then
light alone will separate its oxygen, and leave muriatic acid.
Such, indeed, is the affinity existing between the muriatic
acid basis and water, that those muriates which of themselves
resist decomposition at a red heat, when exposed at that tem-
perature to the vapour of water, are speedily resolved into ga-
seous muriatic acid, and. their peculiar bases.

By restoring the theory of Lavoisier and BerrHo.ier, we
get rid of those mysterious and almost incomprehensible trans-
formations which a drop of water has been lately conceived to
produce on some of the muriates. Dried sea-salt, for example,
when viewed as a compound of chlorine and sodium, is no
sooner moistened, than. a portion of water resolves itself into
oxygen and hydrogen, whence result soda and hydrochloric
acid, and a solution of muriate of soda. Expel the drop of
water, we have a chloride of sodium once more; and we may
repeat this invisible change for an indefinite number of times
by the addition or subtraction of a little moisture. Thus we
must consider dry salt and moist salt to be bodies widely and
essentially different, the former containing neither alkali nor

Vou. VIII. P. Il. Uu acid,

338 EXPERIMENTS ON THE RELATION

acid, while the latter contains both. This supposition, which
the chloridic theory compels us to make, must surely be rec-
koned somewhat violent.

Description of an Apparatus for the Analysis of Gaseous Matter
by Explosion.

The analysis of combustible gases, and supporters of com-
bustion, reciprocally, by explosion, with the electric spark,
furnishes, when it can be applied, one of the speediest and

most elegant methods of chemical research. The risk of fai- -

lure to which the chemist is exposed, in operating with the
simple tube, from the ejection of the mercury, and escape or
introduction of air; or of injury from the bursting of the glass,
by the forcible expansion of some gaseous mixtures, has given
rise to several modifications of apparatus.

Votra’s mechanism, which is employed very much at Paris,
is complex and expensive *, while it is hardly applicable to ex-
periments over mercury. Mr Perpys’s ingenious contrivance,
in which the glass-tube is connected with a metallic spring, to
diminish the shock of explosion, is liable also to some of the
above objections.

A very simple form of instrument occurred to me about two
years ago, in which the atmospheric air, the most elastic and
economical of all springs, is employed to receive and deaden
the recoil. Having frequently used it since that time, I can

now

* The price of the apparatus is about three guineas.

PS et SE ag ~~

diameter of from 32; to 34; of an bali Its legs

9 inches long. ‘The open extremity is slightly

BETWEEN MURIATIC ACID AND CHLORINE. 339

now recommend it to the chemical world, as possessing every
requisite advantage of convenience, enamine safety and pre-
cision.

It is represented on the margin.
It consists of a gine ephon, having an interior

’

are of nearly eat ieeeth, each being from 6 to

funnel-shaped ; the other is hermetically sealed ;
and has inserted near it, by the blow-pipe, two
platina wires. The outer.end of the one wire is
incurvated across, so as nearly to touch the edge:
of the aperture ; that of the other is formed into.
a little hook, to allow a small spherical button.
to be attached to it, when the electrical spark is to be transmit-
ted *. The two legs of the syphon are from } to-} inch asun-
der.

The sealed leg is graduated, by can ai successively.
equal weights of mercury from a measure glass-tube. Seven
ounces Troy and.66 grains, occupy the space of a cubic inch ;
and 34+ grains represent. +4; part.of that volume. The other

Jeg may be graduated also, though. this.is not necessary. The
instrument is then finished.

To use it, we first fill the whole he with mercury or
water, which a little practice will render easy.. We then intro-
duce into the open leg, plunged into a pneumatic trough, any
convenient quantity of the gases, from a glass-measure tube
containing them previously mixed in determinate proportions.
Applying a finger to the orifice, we next remove it from the

trough in which it stands, like a simple tube; and by a little

dexterity,

* In the figure, the ball should have been represented pendent from a hook.

340 EXPERIMENTS ON THE RELATION

dexterity, we transfer the gas into the sealed leg of the syphon.
When we conceive enough to have been passed up, we remove
the finger, and next bring the mercury to a level in both legs,
either by the addition of a few drops, or by the displacement
of a portion, by thrusting down into it a small cylinder of
wood. We now ascertain, by careful inspection, the volume
of included gas. Applying the fore-finger again to the orifice,
so as also to touch the end of the platina wire, we then ap-
proach the pendent ball or button to the electrical. machine,
and transmit the spark. Even when the included gas is consi-
derable in quantity, and of a strongly explosive power, we feel
at the instant nothing but a slight push or pressure on the tip
of the finger. After explosion, when condensation of volume
ensues, the finger will feel pressed down to the orifice by the
superincumbent atmosphere. On gradually sliding the finger
to one side, and admitting the air, the mercurial column in the
sealed leg will rise more or less above that in the other. We
then pour in this liquid metal, till the equilibrium be again re-
stored, when we read off as before, wi:hout any reduction, the
true resulting volume of gas.

As we ought always to leave two inches or more of air be-
tween the finger and the mercury, this atmospheric column
serves as a perfect recoil spring, enabling us to explode very
large quantities without any inconvenience or danger. The
manipulation is also, after a little practice, as easy as that of
the single tube. But a peculiar advantage of this detachable
instrument, is to enable us to keep our pneumatic troughs and
electrical machine at any distance which convenience may re-
quire ; even in different chambers, which, in the case of wet
weather, or a damp apartment, may be found necessary to en-
sure electrical excitation. In the immediate vicinity of the
water pneumatic cistern, we know how often the electric spark

refuses

or ae

BETWEEN MURIATIC ACID AND CHLORINE. 341

refuses to issue from a good electrophorus, or even little ma-
chine. Besides, no discharging rod or communicating-wire is
here required. Holding the eudiometer in the left hand, we
turn the handle of the machine, or lift the electrophorus plate
with the right, and approaching the little ball, the explosion
ensues. The electrician is well aware, that a spark so small as
to excite no unpleasant feeling in the finger, is capable, when
drawn off by a smooth ball, of inflaming combustible gas.
Even this trifling circumstance may be obviated, by hanging
on a’slender wire, instead of applying the finger.

We may analyse the residual gaseous matter, by introducing
either a liquid or a solid re-agent. We first fill the open leg
nearly to the brim with quicksilver, and then place over it the
substance whose action on the gas we wish to try. If liquid,
it may be passed round into the sealed leg among the gas ; but
if solid, fused potash for example, the gas must be brought
round into the open leg, its orifice having been previously clo-

sed with a cork or. stopper. After a proper interval, the gas

being transferred back into the graduated tube, the change of
its volume may be accurately determined. With this eudio-
meter, and a small mercurial pneumatic cistern, we may per-
form pneumatic analyses on a very considerable scale.

It may be desirable in some cases, to have ready access to the
graduated leg, in order to dry it speedily. This advantage is
obtained, by closing the end of the syphon, not hermetically,
but with a little brass cap screwed on, traversed vertically by a
platina wire insulated in a bit of thermometer tube. . After
the apparatus has been charged with gas for explosion, we con-
nect the spherical button with the top of the wire.

With the above instrument I have exploded half a cubic
inch of hydrogen mixed with a quarter of a cubic inch of oxy-

gen ;

842 EXPERIMENTS ON THE RELATION

gen; as also, a bulk nearly equal of an olefiant gas explosive
mixture, without any unpleasant concussion or noise ; so com-
pletely does the air-chamber abate the expansive violence, as
~ well as the loudness of the report. Projection of the mercury,
or displacement of the gas, is obviously impossible.. .

PART |

Hil ee a >

[ 343 ]

PART IL

(Read Jan. 19. 1818. )

EXPERIMENTS MADE WITH THE VIEW OF DETERMINING THE RELA~
TION BETWEEN MURIATIC ACID AND CHLORINE.

To the inferences which I have ventured to draw, from the
experimental results detailed in the preceding part of this pa-
per, two objections may be offered.

First, That the aqueous product obtained in the decomposi-
tion of dry sal ammoniac, by ignited metallic laminze, may pos-
sibly be derived from the azote of the ammonia, supposing azote
not to be a distinct elementary substance, but a peculiar oxide
of hydrogen. This notion occurred to me at an early period,
in consequence of the anomalous, and unaccountable disap-
pearance, of a portion of ammonia, and the concomitant pro-
duction of water, as described in my experimental researches
on the ammoniacal salts. ‘To determine how far this view was
correct in the present instance, I made the following experi-
ment: Into a tube of green glass, sealed at one end, I put
30 gr. of desiccated sal ammoniac. Over it 200 gr. of pure
iron turnings were placed, which occupied 5 inches of the.
tube. The open end of this was connected by a collar of
caoutchouc, with a narrow tube of crystal glass, having a small

: sphere

344 EXPERIMENTS ON THE RELATION

sphere blown in its middle, and its other extremity iia
into pure water, in a glass pneumatic cistern.

When the part ar the green glass tube where the turnings
Jay, was brought to ignition very visible in day-light, it was
moved forward with its supporting semi-cylinder of iron, by
imperceptible degrees. Thus the salt was exhaled from the
bottom, so slowly, that its vapour, in traversing the numerous
convolutions of the iron laminz, was almost entirely decompo-
sed into its constituent gases. The muriatic acid gas was (as
formerly stated) partly condensed into muriate of iron, partly
into liquid acid in the bulb, and partly into the water in the
glass cistern.

Of permanent gaseous matter 106 cubic inches were collec-
ted, after the whole salt had been sublimed from the bottom of
the tube. One hundred cubic inches of these were found by
explosion with oxygen in my eudiometer, to consist of 77 hy-
drogen + 23 azote. Hence the total product of 106 cubic
inches was composed of 81.62 hydrogen, and 24.38 azote.

Now 20 grains of sal ammoniac contain 9.66 gr. of ammo-
nia. And since 18.178 gr. of this alkaline gas occupy the vo-
lume of 100 cubic inches, but are resolvable into double that
volume, or 200 cubic inches of constituent gases; therefore
9.66 gr. of ammonia will give by their entire decomposition
106.28 cubic inches of gaseous products. Of these, one-fourth
according to M. Gay Lussac’s theory of volumes, is azote, and
three-fourths hydrogen ; or 26.57 of the former, and 79.71 of
the latter.

Hence we see that the total bulk of evolved gases, coincides
very nearly with the quantity known to exist in the ammonia.
The azote, therefore, is not concerned in the production of the
water. The deficiency of about two cubic inches of this gas,
may be fairly ascribed to a small portion of the salt having

escaped

ae Sere

Se ee eee eee

BETWEEN MURIATIC ACID AND. CHLORINE. 345

escaped decomposition. The excess in the proportion of hy-

drogen, is due to the decomposition of the water of the muria-
tic acid, in the formation of the muriate of iron. The muria-
tic acid was precipitated from the dissolved and filtered muri-
ate of iron, as well as from the liquid of the bulb, and of the
trough, by nitrate of silver, and the muriate of silver corre-
sponded very nearly with the quantity which 30 grains of sal
ammoniac ought to afford. Of ignited red oxide of iron, treat-
ed with nitric acid, there was obtained 8.8 grains. These are
equivalent, as we shall find in the sequel, to 19.06 gr. of the
peculiar white muriate of iron formed in this process.

Having thus, I presume, given a satisfactory answer to the.
first objection, I shall proceed to the second. This may be ur-
ged by those who conceive that common sal ammoniac tho-
roughly desiccated by heat, and the salt resulting from the
combination of the acid, and alkaline gases, in a dry state, are
not identical in their composition.

Though the very numerous experiments which I had. for-
merly made on the ammoniacal salts, had entirely satisfied me
that well dried muriate of ammonia is uniform in its composi-
tion, in whatever way prepared ; yet I deemed it a duty I ow-
ed to those who might entertain doubts on the subject, to make
the analysis by ignited iron, of sal ammoniac formed from dry
gaseous matter.

Accordingly, muriatic acid gas was evolved without heat
from dry muriate of soda, and concentrated sulphuric acid ; and
ammoniacal gas, from a mixture of dry lime and dry sal am-
moniac. Each gas being shewly generated, and slowly passed
along a tube of thin ies) three feet long, surrounded with pa-
per, kept moist with ether, was brought! into contact with the
other, in a small glass globe, furnished with two tubulures.

Thirty-five grains of a brilliant white and very light pulveru-
Vox. VIII. P. I. Xx lent

346 EXPERIMENTS ON THE RELATION

lent matter, like magnesia, were obtained. These being heat-
ed for some time in a platina capsule, on a sand bath, to a
temperature just under sublimation, lost exactly half a grain.
The salt was found perfectly neutral by litmus paper.

Twenty grains of this hot and dry salt, were pressed down
to the sealed end of a green glass tube ; and 120 grains of pure
iron turnings being put over them, the former arrangement of
furnace, communicating tube, and mercurial trough, was adopt-
ed. After some hours of careful igneous decomposition, about
three grains of liquid were obtained. A similar portion of
muriatic acid gas, to what is formerly stated, was evolved,
along with the gaseous elements of ammonia. Thus I conceive
the second objection to be done away.

To place the identity of the two differently prepared salts,
in the clearest light, I shall state one additional experiment.
I took 5 gr. of that made by gaseous combination, and 5 gr. of
the common kind, both well dried, and dissolving them in wa-
ter, precipitated the whole of their acid, by nitrate of silver.
The gently ignited muriate of silver, obtained from each, was
almost exactly equal; the minute fractional difference, being
an excess on the side of the ordinary sal ammoniac. Hence
we see, that the latter contains as much acid, and consequent-
ly as little of the base or ammoniacal hydrate, (as we may now
term it), as the former.

Doctor Murray, in the able critique which he has given, in
his valuable System of Chemistry, on the chloridic hypothesis,
adduces some experiments of his own, which he conceives
establish the opposite, or oxymuriatic doctrine. They consist-
ed in procuring by heat a visible portion of aqueous. matter,
from the saline compound of ammoniacal and muriatic acid

gases,

BETWEEN MURIATIC ACID AND CHLORINE. 347

gases, both dried previous to their union. He heated the salt
by itself, or passed it through hot charcoal. ‘

I have exposed the above salt, as well as ordinary sal ammo-
niac, to very numerous and diversified trials of the same kind,
but never could obtain in similar circumstances, any satisfac-
tory product of water. Nor can I imagine on what principle
this profound and ingenious chemist should have expected to
obtain water from such sal ammoniac, by the agency of heat,
or of heated charcoal. The water present in muriatic acid gas,
by the old theory, which he espoused, is evidently combined,
not hygrometric water ; and ammoniacal gas certainly contains
none of that liquid. Mains when the two dried gases unite to
form a solid salt, their whole ponderable matter is condensed
or fixed in it ; and whatever existed in both these components,
has become a permanent and essential constituent of the com-
pound. One hundred cubic inches of muriatic acid gas, weigh-
ing 38.04 gr., unite to 100 cubic inches of ammoniacal gas,
weighing 18.17 gr. ; together affording exactly 56.21 gr. of sal
ammoniac. ‘

Now, whatever water existed in the acid gas, is indissolubly
attached to the very existence of the salt, and will always sub-
lime along with it, when heat is applied. Nay, though by a.
very intense heat, we resolve the solid into its ultimate ele-
mentary constituents, we shall recover nothing but hydrogen,
azote, and muriatic acid gases, each as hygrometrically dry as
before. It would, indeed, to my apprehension, be as reason-
able to hope, to extract, by the agency of heat, the combined
water of concentrated oil of vitriol. We shall only vaporize
or distil; the water rising infallibly with the oxygen and sul-
phur ; as it rises with the sal ammoniac, being essential to its
first formation, and future existence. In both these instances,
it is solely by fixing the acid with a base, in some salt, which

x2 requires

348 ‘EXPERIMENTS ON THE RELATION

requires no water of composition, that we can ever expect to
obtain the combined or latent water of sulphuric acid, or of
muriate of ammonia. By this general principle, all my efforts
have been directed.

I shall now endeavour to demonstrate, by particular experi-
ments, the accuracy of these views.

1, Sal ammoniac was put down to the sealed end of a glass-
tube; ‘over it was placed a few inches of river sand, which, af-
ter having been digested with muriatic acid, had been well
edulcorated with water, and ignited, in a platina crucible. On
passing the vapour of the salt, through the ignited sand, liquid
of a reddish-brown colour was copiously condensed in the pro-
jecting and cool part of the tube. This liquid was acidulous
muriate of iron. I naturally ascribed the origin of this to the
red oxide of iron, still contained in the sand after the above
operations.

2. To verify this idea, 1 then took ‘pounded flints, and ob-
tained from the same quantity of salt, in various repetitions of
the process, a very small quantity of blue liquid, which seemed
to be an ammoniacal solution of copper, by its colour and
smell.

3. I next had recourse to quartz nearly pure. The quanti-
ty of liquid obtained in the same circumstances, was now very
inconsiderable indeed ; and I conceived it might be ascribed to
some interspersed particles of mica and felspar, whose alu-
mina might fix a little of the dry acid, and leave water of am-
monia.

4, When pure rock-crystal was employed, the aqueous pro-
duct became almost evanescent. The salt sublimed through
the ignited quartz powder, without any apparent decomposi-
tion.

5. When

0 Eee

BETWEEN MURIATIC ACID AND CHLORINE. 349 ©

5. When strongly calcined charcoal was employed, I obtain-
ed no traces of water at all. It will, moreover, be readily

‘granted by every chemist, that, from the equivocal nature of

common charcoal, as prepared with greater or less care, and
from the uncertainty of expelling the whole gaseous matter,
and moisture it so greedily imbibes, no important inference
can be drawn from any results in which it is concerned *.

The traces of moisture which Dr ‘Murray observed in his
experiments, must have been the adhering or hygrometric wa-

‘ter‘of the sal ammoniac. He has indeed assigned some hypo-

thetical reasons, why sal ammoniac owght not to attract mois-
ture from the air. I shall confront them with the results of
experiments

* If mere heat can separate the combined water of sal ammoniac, then the
salt, which, after passing through ignited quartz, has concreted on the verge of
ignition, being nearly anhydrous, will, in an equal weight, contain more acid
than before transmission. It will in fact bear the same relation to common sal
ammoniac, that ignited sulphate of soda does to the crystallised salt. Having
transmitted, in the state of vapour, the salt condensed from the dry gases,
through ignited quartz, I took 10 gr. of the cake, consolidated just beyond: the
quartz ; and dissolving them in water, decomposed by nitrate of silver, when I
obtained 27 gr- of dry muriate of silver, being the quantity precisely equivalent

to 10 gr. of ordinary muriate of ammonia. (See Wott. Scale of Chem. Equiv.)

Hence it is evident, that ignited sal ammoniac has undergone no change in its
constitution. There was obtained one-tenth of a grain of liquid in that experi-
ment, in which 20 gr. of salt had been passed through the quartz; but this,
though colourless rock-crystal, betrayed the presence of iron in its composition.
For, the liquid stained the paper on which it was withdrawn, of a yellow colour;
and the sublimed salt had, faintly, the same hue. ‘The resulting muriate of sil-
ver partook, a little, of the brown tinge, of peroxide of iron. I therefore ascrib-
ed the produetion of liquid to the action of the oxide of iron on the bydepgen of.
the ammonia,

$50 EXPERIMENTS ON THE RELATION

experiments very carefully conducted ; and we shall find, that
though this salt, is not, perhaps in strict chemical language,
deliquescent, yet it is capable of absorbing or attracting from
the atmosphere a very notable portion of water. This, how-
ever, may be totally expelled, by keeping the salt for a short
time in a temperature of from 200° to 300° of Fahrenheit,
when it resumes exactly its pristine weight.

Pulverised sal ammoniac was desiccated in a platina capsule,
at a heat somewhat below that of its sublimation. It was then
found to weigh 49 gr. I placed the capsule on a shelf in my
apartment. On re-weighing it, at the end of two days, the
salt was found to have become heavier by 3.1 gr.; which
amounts to more than six parts in the hundred. Sal ammo-
niac from gaseous combination exhibits the same phenome-
non; and probably, from the extreme comminution of the
powder, to a still greater degree. It even becomes pasty. The
quantity of this adhering or hygrometric water, will vary no
doubt with the weather or climate, as is the case with muriate
of soda *.

It may be said, Since our sole object in decomposing sal am-
moniac, by metallic lamina, is to obtain from its acid consti-
tuent the water which it is supposed intimately to contain, and
to carry into that salt ; why not employ directly dry muriatic
acid gas, in such researches? My only answer is, that in de-
siccated sal ammoniac, we conveniently find the acid in a state

hygrometrically

* In clear frosty weather, or in a very dry apartment, where muriate of lime
would crystallise, the ammoniacal salt acquires weight very slowly. Fifty grains
of that from gaseous combination, just heated in a platina capsule, to near its
subliming temperature, being put into the scale of a sensible balance, became
heavier by half a grain in two minutes ; after which, in the above circumstances,
no further absorption of moisture was perceptible for an hour. The experiments
detailed in the text were made, when the air was considerably loaded with mois-
ture.

wae:

- BETWEEN MURIATIC ACID AND CHLORINE. 351

hygrometrically dry. Unwilling, however, to shelter myself
behind such an apology, I have thrice made the experiment
with this acid gas, and have obtained each time a most satis-
factory result.

Pure iron turnings were introduced into a green glass tube
about 4 feet long; and they were made to occupy about 6

_ Inches of it, near one end. To this was luted, the tube of com-

munication with the mercurial trough. The part containing
the turnings, rested on the semicylinder of iron, within the fur-
nace. To the other end, which was about 3 feet from the furnace,
the beak of a tubulated retort was luted. Into this, which con-
tained dry muriate of soda, and which was furnished with a sy-
phon-tube of safety, concentrated sulphuric acid was slowly drop-
ped. ‘The projecting green glass tube, with the neck of the re-
tort, altogether about four feet long, were surrounded with pa-
per kept moist with ether, as was also the tube of communica-
tion, on the other side, with its bulb. As soon as I found that
the gas escaping in the pneumatic trough was muriatic acid,
free from admixture with common air, the charcoal furnace
was kindled. The heat being gradually raised to bright igni-
tion, whilst the acid gas was slowly disengaged, in the cold
retort, I found at the end of a short period, that liquid was
condensing i in the bulb, though no traces of moisture ever ap-
peared within the long tube, between the retort and the fur-
nace. The moisture seta 2 in a very slow, but regular pro-
gression. At the end of three hours the quantity had become
considerable. In one case, it amounted to nearly 6 grains. It
was liquid muriatic acid. During the whole process, hydrogen
and muriatic acid gases escaped through. the mercury, in the

proportion, by volume, of 13 of the former to 1 of the latter.
This acid gas, as it issues hot from the furnace, i is very apt
to take up the deposited moisture, unless we screen the tube
from

352 "XPERIMENTS ON THE RELATION

from the fire, and attend diligently to the application of the
ether. Dry muriatic acid gas, and common air, do not affect
iron in the cold, at least during a period equal to their joint
application in the present case, as [have found by experiment ina
graduated glass-tube over quicksilver ; and as the whole atmo-
spheric air was expelled, before the application of heat, the ef-
fect is solely due to the acid gas, as, indeed, its progressive in-
crease, with the duration of the process, sufficiently attest.
The oxygen of the atmosphere could have no influence on the
result *. '

There was found within the tube, near the end farthest from
the retort, on the verge of the ignited part, a white pulverulent
matter, glistening like snow, and the adjoining laminz of iron,
were encrusted with the same substance, in spangling crystal- .
line plates.

This powder dissolves readily in water. Into recently boil-
ed water, when a little of it was put, and a small fragment of
crystallised prussiate of potash was added, a greyish cloud ap-
peared, speedily becoming blue. Tincture of galls dropped
into a similar solution, gave the characteristic purple tinge of
iron. Thirteen parts of it by weight, being ignited in a small
platina tray, evolved copiously a dark-brown smoke, smelling
of muriatic acid, and left 6 parts, which were red oxide of iron.
But 13 of green muriate, by Dr Wot.asron’s scale, are equiva-
lent to 8 of red oxide. Does the above muriate contain the

atomic

* M. Gay Lussac, in his Recherches Physico-chimiques, describes a similar
experiment, but without the production of water. If the utmost precautions be
not taken, to keep the condensing tube at a very low temperature, the expanded
and heated acid gas will readily carry off the moisture, as I found in one experi-
ment. The neglect of these precautions will account for the difference of
M. Gay Lussac’s result.

BETWEEN MURIATIC ACID AND CHLORINE. 3538

atomic protoxide of iron, hitherto unknown? This question
must be answered by future researches.

I tried to determine the proportion of muriatic acid in the
above muriate of iron, by nitrate of silver. The quantity on
which I operated was, however, too small to permit me, to
place much confidence in the result. But one circumstance
arrested my attention. A portion of revived silver was found
at the bottom of the glass capsule, on pouring off the prep
tated muriate.

On the general principle of research, above stated, the pro-

duct of water or liquid, will be proportionate to the quantity

of muriatic acid gas, condensed into muriate of iron. Hence,
to obtain large results, it is proper to have a considerable por-
tion of iron laminze, placed just at, or a little beyond, the limit
of ignition.

_ From the whole of the preceding experiments, we may legi-
timately conclude, that muriatic acid gas hygrometrically dry,
contains much combined water. And since that gas results
from the union of chlorine and hydrogen in equal volumes,
each likewise hygrometrically dry, the above water must be
formed in consequence of the hydrogen finding oxygen in the
chlorine, for its saturation. Chlorine is therefore Sara
tic, or Oxygenated muriatic acid.

My experimental examination of iodine, has further led me
to conclude, that this curious substance is not entitled to rank
in the same class. with chlorine, but with sulphur. The details.
will form the subject of a separate memoir.

Vou. VIII, P. II. Yy XVIII.

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XVIII. On the Laws which regulate the Distribution of the
Polarising Force in Plates, Tubes, and Cylinders of
Glass, that have received the Polarising Structure.
By Davin Brewster, LL. D. F. B.S. Lonp, & Eni.

( Read June 17. 1816.)

I. the Philosophical Transactions for 1816, I have described
at great length the various. phenomena which are exhibited by
glass and other substances to which the property of double re-
fraction has been communicated by heat, by rapid cooling, by
evaporation, or by mechanical compression and dilatation. In
pursuing the same subject, I have observed many singular facts
respecting the developement of new axes, by a:change in the
form and condition of the plates; and by submitting the phe-
nomena to accurate measurement,. I have succeeded in deter-
mining the laws which regulate the distribution of the polari-
‘sing force. A brief account of these results will form the sub-
ject of the following paper..

1. On Plates of Glass with One Axis of Polarisation:

If we take a plate of glass perfectly circular, and communi-
cate to it the polarising structure, either transiently, by the
transmission of heat from its circumference to its centre, or
permanently, by cooling it rapidly, when it has been made red
hot, we shall find that it will exhibit, when exposed to pola-
rised light, a system of rings traversed by a black rectangular
cross. This system of rings is precisely the same, both in ap-
pearance and in the character of its tints, as the system seen

: yA a along

354 ON THE DISTRIBUTION OF THE POLARISING FORCE

along the axis of Ice, Quartz, &c. and other crystals of the po-
sitive class.

If the circular plate of glass, on the contrary, receive the po-
larising structure transiently, by heating it uniformly in boil-
ing oil, and allowing it to cool rapidly, it will exhibit a similar
system of rings ; but this system has a negative polarisation,
like the rings formed by Calcareous spar, Beryl, &c. and other
crystals of the negative class.

This opposition in the character of the two plates may be finely
observed, by combining them together. ‘The resulting system
of rings, when two positive or two negative plates are combined,
will be the same as that which would have been produced by a
plate equal to the sum of their thicknesses ; but when the one
is positive, and the other negative, the resulting system will be
that which would be produced by a plate equal to the differ-
ence of their thicknesses. Hence, when the negative system is
exactly equal to the positive system, they will destroy each
others effects, and the compound plate will have no action
whatever upon polarised light.

By comparing the value of the tints with their distances from
the centre of the plate, I have found, that they vary as the ©
squares of their distances from the axis. Hence if T is the
tint which corresponds to any distance D, the tint ¢ correspon-
ding to any other distance d, will be found by the formula

“Te
wt

2. On Plates of Glass with Two Aves of Polarisation.

When a plate of glass deviates from the circular form, and is
either elliptical or rectangular, it has two axes of polarisation,
one of which is perpendicular to the plane of the plate, and
the other at right angles to it, and lying in the plane of the
plate. When the plate has received the polarising structure

transiently, by the transmission of heat, or permanently, by
being

IN PLATES, TUBES, AND CYLINDERS OF GLASS. 355

being cooled rapidly from a red-heat, the axis perpendicular
to the plane of the plate (which is always the principal axis),
is positive ; but when the polarising structure is communicated
by heating the plate in boiling oil, and then cooling it rapidly,
the principal axis is negative.

By measuring carefully the distances of the tints from the
centre of the plate, I have found the following formula, dedu-
ced from the supposition of two axes, perfectly correct, viz.

t= Toa » where D is the distance of either of the black

fringes or Jines of no polarisation from the centre of the plate.
The term Se represents the influence of the principal axis,
and would have given us the tint ¢ if that axis had existed
alone. But as the axis in the plane of the plate produces an
uniform tint T in every part of the plate, which acts in oppo-
sition to the other tint; the tint ¢ must be equal to the differ-
2
ence of these tints, or to T— age
In examining the relative intensities of the two axes in rec-
tangular plates of considerable length, and in elliptical plates,
in which the conjugate axis is very small when compared with
the transverse axis, I have found that D, or half the distance
between the black fringes, is a function of the breadth of the
plate, that is, if B is the breadth of the plate 2D: B= 10: 16.02,
and D=.312B*. As the excentricity of the elliptical plate
diminishes, the value of D diminishes, or the polarising force
of the axis in the plane of the plate diminishes ; and when the
conjugate and transverse axes are equal, D is equal to 0, or the
axis in the plane of the plate is destroyed. In elliptical plates,
the black fringes which are seen when the transverse axis is
inclined 45° to the plane of primitive polarisation, are convex
towards the transverse axis, and their curvature is such, that
they

356 ON THE DISTRIBUTION OF THE POLARISING FORCE

they cut perpendicularly every similar ellipse drawn within the:
plate. Hence, when the ellipse is nearly a circle, the distance
of the fringes will be almost nothing, and each of the fringes

will form two straight lines at right angles to one another, as

in elliptical plates, when the transverse or the conjugate axis is

in the plane of primitive polarisation.

The lines of equal tint at the angles of rectangular plates of
glass, are highly deserving of attention. They are produced.
by the external fringes, and the maximum tint at the angles
is always less than at the edges, and generally higher than the
maximum tint in the middle of the plate. When the external
fringes are two in number, viz. ab, ab’, de, d’e’, as shown
in Plate VII. Fig. 1. ; the outermost, ab, a’b’, terminates at c¢, e,
and the other, de, d’e’, branches off at e, e’, so as to form |
the ellipsis efe’e. The tint increases from this elliptical line
to its centre 0, but decreases from o to p, and from o to q.
When the glass plate is a perfect square, the curve efe’e is a
circle *. In a plate whose maximum tint, in the middle, was a
Blue of the 2d order ; the tint at o was a Pink of the 2d order ;
and that at p and g a White of the 1st order.

3. On the Lines of Equal Tint formed by the Transverse
_ Combination of Plates of Glass.

In the Philosophical Transactions for 1816, I have repre-
sented the Jsochromatic lines, or lines of equal tint, form-
ed by the transverse combination of plates of glass, when
the principal axes are both negative, or both positive + ;
when the principal axis in one is negative, and in the
other positive |; when the two plates receive their structure
by bending || ; and when a bent plate is combined with a plate
formed by heat §. In these various cases, the lines of equal

tint
ee SS ane. = San La ee
* See Phil. Trans. 1916, Plate IV. fig. 29. + Id..Plate II. fig. 3, 4.

+ Id. Plate If. fig. 8. || Td. Plate IX. fig. 9. § Id. Plate IX. fig. 10.

PLATE VI.

Engraved bor the Royal Scotety Tran. Vol. Vill Page 356.

|

ee

Engraved. by Wik D.Lizars E dint

¢
%

IN PLATES, TUBES, AND CYLINDERS OF GLASS. 357

tint will be found to be Hyperbolas, Circles, Ellipses, Straight
Lines and Parabolas.
Let us now suppose,
T T’= the maximum tints of the two plates.
B B’= the breadths of the plates.

x =the distance from the centre of the plate of
any. point where the resulting tint is required.
y = the distance of the same point from the centre

of the other plate.
t ¢ = the tint produced by each plate separately at
the distances « and y, and

¢ = the resulting tint.
.
Then, substituting .312 B instead of its equal D, we have
: Tax 2 q’ 2
i Pe al fue dy eet
312 Be?“ 312 B®’

But, since the Bie eye tint + arising from the combination
is equal to the difference of the two tints, we have

Pgh Lig*
312 B2 + —— 312 312 B® 9 and

me yh ws =") T .312 B? x’
sige ak (= TT" 312 Be

z— T’—T—

Consequently, the lines of equal tint are Hyperbolas. When
feed yl and.B = B, the Sik ae are equilateral, and

of = .312 B? +a%.

When a plate whose Same axis is negative, is crossed
with a plate whose principal axis is positive *, the resulting
tint

* Phil. Trans. 1816, vol. II. fig. 8.

358 ON THE DISTRIBUTION OF THE POLARISING FORCE

tint will be the sum of the ee tints. Hence, in this case
we have

urate Ulam
3128? 312 B?

V+T—- Tots Be
oo ve —
y? = .312B TY ) “7-319 BE *

The lines of equal tint will therefore be El/ipses, as shewn in
Plate VIL. Fig.2. when either the maximum tints, or the breadths.
of the combined plates are not equal.

But, when T = T’ and B = By, we have

—-T+T —

, and

ye =.312 B? (2 eet —a",

Consequently, the lines are in this ease Circles, as shewn in
Phil. Trans. 1816, Plate IT. Fig. 8.

When the two combined plates receive their structure by
bending, the tints do not vary, as the squares of their distances.
from the centre, but simply as their distances. Hence, T being
the maximum tint at the edge of the plate, and B B’ the

breadths of the plate as formerly, we have = :Toa:t; and

Pp

a :T’=y:t, which give

c= a and ’ = ay. Consequently,

a 2Te + 2Ty
LS +r a » and
Be TR

I= oP — TR |
Hence, the lines of equal tint will be Straight lines.
The

i

IN PLATES, TUBES, AND CYLINDERS OF GLASS. 361

. The angle ¢, which the straight lines of equal tint form with
the edges of the plate, will be found by the formula,
iE B
Tang. sS Oi = Py
When x:y=B: By, and when similar sides of the plates

cross each other, we shall have += 0, that. is, the line of no-
polarisation will be the diagonal of the parallelogram formed
by the sides of the two plates *.

When B= By’, and T =T, then

Br
Y= op and.

the straight lines of equal tint will be inclined 45° to the edges
of the plates, for - = 1, which is the tangent of 45°.

When a plate of glass with two axes is combined with a
plate of bent glass +, we have
ay op

a Bs 2 aR a)
v= .312B(1— 7 + ape),
when the concave side of the bent plate crosses a plate with
two axes, in which the principal axis is negative ; or,,
2 2 :

2
1 Ae Gio: |, aie Be OO
2— 312 B a _ 2Ty
Po we Ge ee,

when the convex side of the bent plate crosses a plate with
two axes, in which the principal axis is positive, and vice
versa. Hence, it follows, that the lines of equal tint are here
Parabolas.

Vou. VIII. P. IT. ZZ When

* See Phil. T'rans. 1816, Plate IX. fig. 9. + Id. Plate IX. Fig. 10.

362 ON THE DISTRIBUTION OF THE POLAR!SING FORCE

When T = T’ the line of no-polarisation is a complete para-
bola, passing through the angles of the parallelogram, and ha-
ving its vertex at the very edge of the bent plate. The curves
within it will also be complete parabolas, but all those without
it will be only parabolic segments.

4. On the Distribution of the Polarising Force in Tubes and
Cylinders of Glass.

We have already seen, that circular plates, or cylinders of
glass, have one negative axis, like Quartz ; but when the cylin-
der has the form of a tube, like AB, Plate VII. Fig. 3. the pola-
rising force is distributed in a very remarkable manner. A
black circular fringe mp no forms the line of no-polarisation,
and the coloured fringes are placed on each side of this dark
ring, and concentric with it. The structure on the outside of
mp no is negative like Calcareous spar ; and the structure on the
‘inside positive, like Quartz, &c.; and the effect is exactly the
same as if a plate of glass had been bent into a circular form,
and kept in that position by force.

The breadth of the positive annulus ao is always less than
that of the negative annulus Ao, the former decreasing, and
the latter increasing, as the bore of the tube diminishes ; and
when the bore becomes extremely small, as in Fig. 4. the posi-
tive structure is also extremely small, and sometimes can
scarcely be seen without the aid of a microscope.

In comparing the values of the tints with their distances
from the line m pn o, I have found that they vary as the distan-
ces, in the same manner as in bent glass. Hence it is obvious,
that the glass is in a state of compression within the black
ring mpno, and in a state of dilatation without that ring, and
that the particles are held in a state of violent constraint, en-
tirely different from that position of equilibrium in which they

are placed in plates of glass with one or two axes.
With

IN PLATES, TUBES, AND CYLINDERS OF GLASS. 363

With the view of confirming these results, I took a file with
a very sharp edge, and cut the tube entirely through by a notch
EF, Fig. 5. By this operation the particles were freed from
the state of violence in which they were held, and assumed
the very same arrangement which they never fail to take in
rectangular plates of glass. By exposing the tube, thus divi-
ded, to polarised light, it exhibited the appearance shewn in
Fig. 5. where mp no, m’p’n’o’, are two dark fringes having a
negative structure on the outer side of each, and a positive
structure between them, as in plates of glass with two axes. I
obtained the same result with a tube of a very large bore, ha-
ving its exterior diameter 0.875 of an inch, and its interior dia-
meter 0.816 ; so that the thickness of the glass was only 0.059
of an inch. When the tube is cut into two or more pieces, each
piece has the same structure as a plate of glass with two axes.
By a number of measurements, I have found that the diameter
op, Fig. 3. of the black fringe or circle of no-polarisation, is
a geometrical mean between the interior and exterior diame-

ters of the tube, that is, op = »/ AB xab,

If a tube of glass is brought to a red heat, and then cool-
ed by inserting in its bore a cylinder of iron, or any other
conducting body, the structure will then be the same as is re-

presented in Fig. 5.
If a solid cylinder of glass which has only one structure, is

- perforated in its centre, it will exhibit the appearance in Fig. 3.,

and if it is divided by a notch, it will acquire the structure
shewn in Fig. 5.

When polarised light is transmitted through a Jong cylinder
of unannealed glass, in a line perpendicular to its axis, after
it is immersed in a fluid of the same refractive power, it exhi-
bits the same phenomena as rectangular plates of glass, having
a positive axis perpendicular to its length, and a negative axis
perpendicular to the positive one; but in the cylinder, the ex-

Zz 2 ternal

364 ON THE DISTRIBUTION OF THE POLARISING FORCE

ternal tints do not rise so high, from the diminution in the
thickness of the glass.

The same phenomena are exhibited by a glass-tube AD,
Fig. 6. similarly placed. In this case, however, the maximum
tint does not appear along the line mm, the axis of the tube;
but it is seen both in the lines 6d and dd, equidistant from
mm. This effect is obviously occasioned by the greater thick-
ness of the glass in these directions ; for a and cd are each
greater than Ao-+pm, and the difference is sufficiently great
to overbalance the diminution of the tints at a greater distance
from the principal axis.

In examining very carefully the structure of glass tubes,
when exposed to polarised light, it will be found that they are
as it were divided into different elementary concentric tubes ;
and that in some cases there is an actual separation between
them. Hence, there arises a remarkable singularity in the
progression of the tints. Instead of shading into one another
by imperceptible gradations, each elementary tube has an uni-
form tint of its own, as is represented in Fig. 7. where the
tube AB is divided into four tubes 1,1; 2,2; 3,3; 4,4; the
tube 4,4 is in every part of it a white of the first order ; the
tube 3,3 is every where equally dark, being the black cir-
cular fringe mpno of Fig. 3.; the tubes 2,2 and 4,4 are
a white of the first order; and the tube 1,1 is a yellow of the
first order. Hence it follows, that in tubes which possess this
peculiarity of structure, each elementary tube is uniformly
dense throughout, and that the variation of density takes place
by leaps.

If a portion of a glass tube perfectly annealed, is exposed to
pressure, it exhibits the tints shown in Fig. 8. when the line
mn, joining the points of pressure, is parallel or perpendicular
to the plane of primitive polarisation ; and the tints shown in
Fig. 9. when the same line is inclined 45°to that plane.

5, On

—— Or

IN PLATES, TUBES, AND CYLINDERS OF GLASS. 365

5. On the Conversion of Plates of Glass with One Axis into
Plates with Two Axes.

From the different experiments which I have described,
both in this and in other papers, it appears, that in almost
every case where polarising forces are developed, two negative
structures are separated by a positive structure, or two positive
structures by a negative structure, both of which are simulta-
neously produced, like the two opposite polarities in electrici-
ty and magnetism. When the two structures are disposed in
a different manner, or when only one structure is developed,
the regular arrangement of the polarising forces may be effec-
ted by a slight change in the form or in the mechanical condi-
tion of the plate.

If we take a piece of unannealed glass perfectly circular, we
have only one axis, or one structure, as shewn in Fig. 10., where
AB, CD is the black cross, which preserves the same appearance
by turning the plate round its centre. But if we grind the
smallest quantity from any two opposite sides CB, AD, so as to
induce a slight degree of ellipticity, a new axis is created; the
tint which it produces appears at the centre of the plate, and the
system of rings has the form shewn in Fig. 8., where the inter-
nal structure within the black fringes AD, CB, is negative, and
the two external structures without AD, CB, positive.

If, on the contrary, we now grind a small quantity from
the sides AC, BD, so as to reconvert the elliptical plate into a
circular plate, we shall find that the new axis which was gene-
rated by the change of form, has entirely disappeared, so that
the plate exhibits the figure shewn in Fig. 10.

This singular experiment, in which one of the axes may be
extinguished and revived at pleasure, is worthy of the most

attentive

66 ON THE DISTRIBUTION OF THE POLARISING FORCE

ts

attentive consideration. If the polarising forces depend solely
on the mechanical condition of the particles of the glass, then
it necessarily follows, that the central parts of the glass, which
were in a state of variable expansion when it had a circular
shape, are in a state of variable compression when the glass has
received an elliptical form, and we are presented with a new
law relative to the equilibrium of the cohesive forces in solids
of variable density. But if the variation of density is merely
the means of developing a new agent in the same manner as
heat excites electricity in the tourmaline, or as pressure excites
it in calcareous spar, then we cannot avoid regarding this agent
in the same light as the electrical and magnetical fluid which
are decomposed by certain mechanical operations, and distri-
bute themselves according to regular laws.

But whatever be the origin of the polarising forces, it be-
comes a matter of great importance to discover the law of their
distribution, when they are not controuled by opposite actions,
and to apply this law to the explanation of the phenomena
which they develope when they are either modified or extin-
guished by the external form of the body in which they re-
side.

Those who have studied the papers to which I have already
referred, cannot have failed to remark, that when the polari-
sing forces are unconstrained in their developement, a negative
structure is generated in the middle of the plate, when a posi-
tive structure is generated at one or both of its edges ; and that
the intensity of the negative, is to the intensity of either of the
positive structures, as 10 to 16.02.

In order to apply this principle to a circular plate, let KLHFG,
Tig. 12. be a plate of this description, whose centre is O. Then
if this plate were a part of the rectangular plate ABDC, mn, op
would be the lines of no-polarisation which separate the internal

negative

IN PLATES, TUBES, AND CYLINDERS OF GLASS. 367

negative structure from the two external positive structures.
The tint at a, or any part of the line bc, would be
Te

—— 32 BE but if the circular plate were part of a plate si-

milar to, and at right angles to ABCD, the tint at a, or any
part of the line EOF, would be equal to T; and as this tint is
‘rectangular to the other tint at a, the resulting tint will be
equal to the difference of these tints, or to

ete Td ae

| ee ada Beale He
In like manner, it may be shewn, that in every point of the
2

circular plate, the tint is represented by ae which is the

experimental expression for it already found. In plates,
therefore, that have only a positive structure, the negative
structure still exists, but is overpowered by opposite ac-
tions.

We are now prepared to understand how the negative struc-
ture re-appears, as shewn in Fig. 11., by giving an elliptical form
- to the plate. For, the maximum negative tint produced at O,
in the direction gh, is no longer counterbalanced by the tint
in the direction ef; and therefore the difference of these tints
appears at O, with a negative character. As the points e, f re-
move from O, oras the ellipticity increases, the tint at O gradual-
ly rises till it becomes equal to T, or a times the tint at
g, when the action of the edges at e and f has no longer any
influence at O. The very same results are obtained by the

conversion of a sphere into a spheroid, and they are explicable
upon the same principles.

The

’

368 ON THE DISTRIBUTION OF THE POLARISING FORCE

The distribution of the polarising force at the angles of
square or rectangular plates, characterises. a very remarkable
state of equilibrium among the cohesive forces ;. and this state
of equilibrium is not am accidental result of the mode in which
the heat either enters or leaves the angles of the glass plate,
for the very same distribution takes place when a new angle is
formed, by cutting the plate into two parts.*. In all these
eases, the lines of equal tint are the lines of equal density.

As the two kinds of polarising forces seem to be co-existent
in every part of a glass plate, and as each of them, when it ap-
pears to exist alone, is merely the resultant of two opposite
forces, it is easy to assign a reason for the singular phenome-
na which are exhibited, by dividing a plate of glass into two
parts. The two forces which reside in every part of the glass
cannot be in equilibrio, unless a negative structure is placed
between two positive structures ; and therefore each half of the
elass plate, or each portion of it of the same shape as the whole
plate, must acquire the same property as ‘the plate itself, or
have the forces distributed in the same manner. This view of
the distribution of the polarising forces is analogous to Cov-
romx’s theory of the construction of the magnet. Every ele-
mentary portion of the magnet has a north and south pole, and
therefore wherever it is broken, the fragment must have a
north and south pole, like the magnet of which it formed a.

part.

6. On,

* See Phil. Trans. 1816, p. 82.

IN PLATES, TUBES, AND CYLINDERS OF GLASS. 369

4

6. On the Intensity and Distribution of the Polarising Force in
Plates of Bent Glass.

. In order to ascertain the intensity of the polarising force, as
produced by different degrees of flexure, I placed together two
similar plates A B, C D, Fig. 13, and separated their extremi-
ties by two pieces of glass A C, B D, of equal thickness. After
pressing them into contact at M and N, I observed the maxi-
mum tints which they exhibited at these points, as given in the
following Table.

Length of Plates, Distance of Extre- Thickness of Breadth of the Maximum

or AB. mities, or A C. the Glass. Plate. Tint.
16 inches 0.16 0.133. 0.35 4
13 0.16 0.133 0.35 9
12 0.048 0.207 0:967 10.6

6 0.054 0.133. . 0.35 10.5

With the view of ascertaining the tints which they yielded be-
fore they broke, I took plates, whose thickness was 0.1383 of an
inch, and breadth 0.33. One of these broke when the tint was
10.4, another when the tint was 12, and a third when it had reached
13.55. In the phenomena of bent glass, the polarising force is
distributed in such a manner, that the lines of equal tint are
the lines of equal compression or dilatation, and the tint at the
edge is every where inversely proportional to the radius of cur-
vature.

In order to compare the effects produced by the application of
the same force to plates of. different thicknesses, I placed them
as in Fig.13. The thickness of A B was 133, and its tint 3.4.

Vox. VIII. P, Il. 3A ...- The

370 ON THE DISTRIBUTION OF THE POLARISING FORCE

The thickness of CD was .230, and its tint 10.2. But
133? : 230? = 3.4:10:2; so that the tints and the elasticities
were, in this case, inversely as the squares of the thicknesses.

‘The preceding experiment furnishes us with the principle of
anew instrument, which may be called a Teinometer, for ascer-
taining the elasticities of bodies. The-tints of AB and CD are
obviously measures of the elasticities of the two plates ; so that
the elasticities of plates of glass of different dimensions, or form-
ed of different materials, may be readily determined. The power
of the instrument however, is not limited to glass; for, by
using a glass plate AB as a standard, the other plate CD may
be a plate of metal, or any other opaque substance, whose elas-
ticity it is required to ascertain. The tint of AB, when op-
posed by a plate of equal elasticity, is known by experiment ;
and therefore, the tint which it affords, when opposed by a si-
milar plate, of a substance possessing a‘greater or a less elasti-
city than itself, is a measure of this elasticity. Although I
‘consider the variation of the-tint as an excellent means of de-
termining the degree of curvature, yet the principle o exhibiting
‘ the relative elasticities of two plates, by the application of the
same force, may be employed in an instrument entirely me-
chanical, in which the sagitta of the inflected plate is actually
measured, as in the ingenious machine invented by S’Gravzs-
ANDE.

The chromatic Teinometer is represented in Figs. 14, 15.
and 16. where AB is the standard plate, of well annealed
glass, having its edges highly polished. Along this plate,
there are moved two brass pieces, Sabc, S'a' b'c’, which-can
be fixed in any position, by means of the screws S,S. The
plate CD, where elasticity is to be measured, rests with its lower
edge upon the projection bc, Fig. 15. and with one of its faces
against ab. It is then pressed into contact with the plate AB,

and

IN PLATES, TUBES, AND CYLINDERS OF GLASS. 371

and kept in this position by the wooden holdfast H; the
brass: pieces Sac, S’a'b'c’, having been previously placed at
such a distance from each other, that the two plates will meet
at H, without breaking, or without any permanent change of
form. . The apparatus ER, for observing the tint, is shewn sepa-_
rately in Fig..16. It consists of an eye-piece E, to which is at--
tached a reflector R, made of several plates of the thinnest.
glass, about 14 long and an inch broad, and placed close to each
other. The eye-piece E consists of two tubes, one of which is
moveable within. the other. The moveable tube contains an
achromatic prism, mn, of calcareous-spar, with a convex lens,
op, about an inch in focal length, placed either above or below
it. When.this apparatus is set upon the edge of AB, by means
of the forked arms e, f; the reflector R is turned round, till the
plane of reflection is cut at an-angle of 45°, by the plane of the
plate AB, and is placed at such an.angle, that the light which it
reflects through the edge of the plate AB, and up the tube, is
completely polarised. The moveable tube is then turned round,
till the tints appear on the edge of one of the images of the
glass plate. In order to avoid the confusion arising from two
images, the achromatic prism may be constructed in such a.
manner that only one of the images is visible.

3A 2 XIX

OD TEI Da ES

ee EEE

XIX, Remarks, illustrative of the Scope and Influence of the
Philosophical Writings of Lord Bacon. By Macvey
Napier, Esq, F. R. S. Lond. & Edin. and F. A. 8. Edin.

(Read February 16. 1818.)

Tur obligations of Experimental Physics to the labours of
Lord Bacon, have been largely acknowledged by the genera-
lity of those who have treated of the History of Modern Sci-
ence; insomuch, that the title of Father of Experimental
Philosophy has been oftener conferred upon him than upon
any other of its benefactors. There are some, however, who
seem to think, that there is no good ground for honouring him
with this title, either on account of the merits or the effects of
his writings. They do not indeed deny, that his views as to
the proper objects and method of philosophizing were exten-
sive and just ; but they contend, that he had no peculiar merit
in having stated these views; that all that he taught was vir-
tually and more effectually taught by the discoveries of some
of his contemporaries ; and that, in fact, there are no traces of
his agency to be found in the discoveries that followed *.
These opinions, though they are to be met with in respect-
able

“#¢¢ Atqui Veruamuus ille, qui Germanz Philosophie Restitutor, quin etiam, si
Superis placet, Parens a Bruxero aliisque habetur, quid aliud in Anglia presti-
tit,

374 - ON THE SCOPE AND INFLUENCE OF THE

able books, and in the conversation of intelligent men, seem
to involve no small portion both of error and misconcep-
tion. It cannot be denied, indeed, that at the time when
Bacon wrote, there was a growing tendency to abandon the
ancient systems, and that some successful essays had been made
in that course of inquiry which he recommended ; but, on the
other hand, it appears to me equally clear, that his labours for
the advancement of Science were of such peculiar importance,
and attended with such extensive effects, as to entitle him to a
pre-eminent station among its early reformers and promoters.
It is the object of this paper to offer some remarks, and to
collect some proofs, in support of these views; but, as much
has been already written in illustration of the merits, and but
little in illustration of the effects produced by his philosophical
writings, I shall content myself, at present, with a slight indi-
cation of their general scope, and shall devote the greater part
of my paper to the proofs of their influence. Upon the latter
point, indeed, there seems to exist more of doubt and of mis-
apprehension than upon any other connected with his philo-
sophy*.

In

tit, nisi, ut, qua ratione philosophari deberemus, eo tempore admoneret, quo Ga-
ritzus eadem ipsa ratione philosophari jam in Italia coeperat, ac ceteris, ut idem
facerent, non modo verbis, verum et rebus ipsis gravissimus auctor esset ?°—Fa-
sroni, Vite Italorum doctrina excellentium qui secults xvii. et xvili. floruerunt, vol. i.
p- 223.

——“ C’est Gauiter,” says a French Philosopher of the present day, “* quia
montré Vart de V’interroger par ’expérience. Ona souvent attribué cette gloirea
Bacon; mais ceux qui lui en font honneur, ont été (a notre avis) un peu pro-
digues d’un bien qu'il ne leur appartenait peut-étre pas de dispenser.” —Biogra-
phie Universelle, Tom. xvi. p. 329, Art. Gauiteo; written by M. Brot.

* There cannot be a stronger proof of the misapprehensions alluded to, than

what is furnished in the following passage,’of the interesting article above
mentioned.

SS Eee sy

(ae
Vo

| ne Lay

PHILOSOPHICAL WRITINGS OF LORD BACON. 375

In order to clear the way for this inquiry, I shall begin with
a few remarks-on a late estimate of Bacon’s Philosophy, evi-
dently intended, not merely to depreciate, but to vilify it ; in-
somuch, that it stands remarkably at variance with almost all
that has been hitherto published on that subject. The esti-
mate alluded to is the more worthy of notice, that it has ob-
tained a place in a Literary Journal of great respectability, and
which is supposed by many to speak the sentiments of the

' English Universities in matters of philosophy.

It is pretty well known, I presume, that Bacon’s writings have
been recently commented upon by two of our most eminent
philosophers ; by the one, in reference to their connection with
the Philosophy of the Mind *; and by the other, in reference
to their more apparent object, the explaining the method by
which to extend our knowledge of the Material World +.
Both of them represent Bacon as the first who clearly and fully
pointed out the legitimate rules and ends of philosophical in-

quiry ;

mentioned. ‘¢ Si Bacon a eu tant de part aux découvertes qui se sont faites
aprés lui dans Jes sciences, qu’on nous montre donc un seul fait, un seul résul-
tat de son invention, qui soit de quelque utilité aujourd’hui: ou, si ses prin-
cipes généraux sont tellement feconds, qwils aient pu, comme on l’assure, lui faire
pressentir un grand nombre de decouvertes modernes, il est présumable qu’on
n’ a pas encore épuisé tout ce que contient son Livre; et dans ce cas, ceux qui
disent que nous lui devons tant de choses, devraient essayer d’en tirer d’avance
quelques-unes des découvertes dont la methode de Gatitez nous enrichit tous
les jours.”—Biog. Universelle, in loc. cit.

* See Mr Srewart’s Dissertation on the Progress of Metaphysical, Ethical, and
Political Philosophy, prefixed to the Supplement to the Encyclopedia Britannica.

+ See Professor Prayratr’s Dissertation on the Progress of Mathematical tee
Physical Science, prefixed to the same work.

876 ON THE SCOPE AND INFLUENCE OF THE

quiry ; and both consider his writings as fixing a new and
important era in the history of Modern Science. The obser-
vations made by the former upon these points, have been exa-
mined at considerable length in an able article of the Journal
referred to; and the following passage contains the sum of
what is there advanced in regard to the general scope and cha-
racter of Bacon’s Philosophy. “ The topic on which Mr
“ Srewarr chiefly dwells, while panegyrizing the Philosophy
“ of Bacon, is the respect which it pays to the limits, the laws,
“ and resources of the human understanding ; and this is sure-
“ ly the most extraordinary topic of any which he has select-
“ ed. There is scarcely a page in the Novum Organum, that
“ does not furnish a contradiction to it.—So little, indeed,
“ can Bacon be considered as having risen in any great de-
“ gree above the age in which -he lived, with respect to his
“ views as to the proper aim of philosophy, or the proper
“ limits of the human understanding, that he even goes
“ so far as to give us formal receipts for the making of
“ gold, and performing other prodigies, which he tells us he
“ judges very possible. With the exception of the disciples of
“ Raymonp Lutty and Jorpano Bruno, the extravagant spe-
“ culations in which Bacon wished to embark philosophy, had

“ been long abandoned by sober inquirers *.”
It

* Quarterly Review, No. xxxiii. p. 50.—The writer of this article seems to have
been anxious to find some great names to countenance what he has advanced in
regard to the very inferior merits of Bacon’s philosophical writings. What his
success has been in this endeavour, the following extract will shew.

« IT remember, said Sir Josuva Reynoxps, that Mr Burke, speaking of Ba-
eon’s Essays, said, he thought them the best of his works. Dr Jounson was
of opinion, that their excellence and their value consisted in their being obser-

vations of a strong mind operating upon life; and in consequence you find
there

a

Sp ee aren *

.
‘

PHILOSOPHICAL WRITINGS OF LORD BACON. 377

It is to be wished, that this writer had explained to us, to
what delusion it has been owing, that so many enlightened
persons have, for more than a century and a half, concurred
in extolling Bacon, for his endeavours to withdraw philoso-
phy from “ extravagant speculation,’ and to give it a di-
rection and a method, calculated to improve the condition,
as well as the knowledge, of mankind. Have they all been
in error, and must Bacon be branded with the imputation
of ignorance of the business of philosophy, and the limits of
the understanding, merely because he has speculated upon
the possibility of making gold? Is this circumstance enough
to establish an affinity between the general aims of his philo-
sophy and the extravagant pursuits of the Alchymists? A
very few words will suffice upon this point.

Wor. ViIlb-P. 11. 3B There

there what you seldom find in other works.”"—Account of Sir Josuua Rey-
wotps, prefixed to Marowe’s edition of his Discourses.

“ We are glad,” the Reviewer adds, “‘ to be able to defend our opinions con-
cerning the inferior merits of Bacon’s philosophical writings, compared with his
other works, from the charge of singularity or presumption, by eet our-
selves under the authority of such names as Burke and Jounson.”

It is very observable, that, so far as Dr Jonnson’s authority is concerned, he
does not appear, in the conversation referred to, to have made any compa-
rison whatever between Bacon’s Essays and his other works: he only made a re-
mark descriptive of the Essays, in which every one who has perused them will rea-
dily concur ; and besides, the Reviewer ought to have known, that Jounson has,
in one of his papers in the Adventurer, represented Bacon as the only Modern
worthy of being compared, in a philosophical point of view, with Newron ;
thereby showing, that he must have held the philosophical works of the former
in the highest possible degree of estimation. Great as the excellence of the
Essays undoubtedly is, it is difficult to believe, that such a man as Burke could
deliberately rate them as of higher merit than the De Augmentis Scientiarum
and Novum Organum. There is need of some better evidence, surely, that he
had formed a deliberate opinion to that effect, than what is furnished by the
scrap of conversation which forms the Reviewer's only document of proof.

378 . ON THE SCOPE AND INFLUENCE OF THE

There can be no doubt, that Bacon did believe in the possi-
bility of discovering the means of converting other substances
into gold; a belief, which was far from being so complete-
ly abandoned by all “ sober inquirers,” as this writer imagines ;
for it was entertained by Boyz, and some other experimen-
talists, and not greatly discouraged even by Newron, at a
period when experimental philosophy was much farther ad-
vanced *. There was no man of his day more thoroughly ap-
prised than Bacon was, of the follies of the Alchymists, or who
has mentioned them in terms of stronger ridicule and reproba-
tion +. He nowhere holds out the making of gold as a prime
object of philosophical inquiry ; on the contrary, he point-
edly censures the Alchymists, with whom he has been so ab-
surdly classed, for directing their main views to such an ob-
ject {. The belief which he entertained as to the possibility
of making gold, had a very different foundation from that
upon which it rested among this fantastical fraternity. With
him, the belief in question formed part of his general belief,
that the essences of all material substances were capable of be-
ing discovered by the inductive process. It was a belief which
flowed from his lofty notions of the yet untried resources of
experimental science. There was then no sufficient stock of
experience to authorise any one to lay it down as an esta-
blished principle, that the knowledge of these essences is

placed

* There is a curious letter upon this subject from Newron to Mr Otpen-
pore, Secretary of the Royal Society, printed in the account of Boyxe, in the
Historical Dictionary. His remarks apply wholly to a particular process of trans-
rautation, and not to the impossibility of the thing itself. See General Historical
and Critical Dictionary, vol. iii. p. 558.

+ See Novum Organum, Lib. i. Aph. 85. 87.
* Ibid. Lib. i. Aph. 70.

PHILOSOPHICAL WRITINGS OF LORD BACON. 879

placed beyond. the reach of scientific discovery. It is not very
surprising, therefore, that Bacon should believe, that a series
of skilfully conducted experiments might ultimately lead to
the detection of the nature or essence of gold; and that
having thus discovered its constituent nature, it would then
be possible to superinduce it upon any other substance. There
is nothing in all this that any way impeaches his respect
to the “ laws and limits of the human understanding.” He
recommended no inquiry upon any other principles than
those of Induction; and he proposed no object to philoso-
phy, which any thing but experience could shew to be unat-
tainable.

But we are farther told, that there is “ scarcely a page in
* the Novum Organum” which does not afford proofs of Ba-
con’s ignorance of the laws and limits of the understanding ;
and that his miscellaneous philosophical pieces seem to have
been written in express contempt of them *. Had this writer |
contented himself with stating, that there are many things in
Bacon’s miscellaneous pieces, which show that he was not ex-
empt from credulity, that his understanding, resplendent as
it was, bore some stains of the scurf and seum of an ignorant
age; or had he only stated that Bacon’s metaphysical notions

‘are sometimes vague and unsound, and his use of language

fanciful and uncertain. his observations might have been: allow-
ed to pass unnoticed, as neither new nor objectionable. But
when he goes so far as to charge the Novum Organum as every
where manifesting a total ignorance of the fundamental condi-
tions of philosophical reasoning, the only respectful conclusion,
I must say, that can be adopted in regard to such an asser-

3B2 . tion

* Quarterly Review, No. =xxiii. p. 50.

380 ON THE SCOPE AND INFLUENCE OF THE

tion is, that it has proceeded from a very imperfect acquain-
- tance with the work in question. For my own part, I confess
myself wholly unable to conceive, how any man of ordinary:
judgment could read the Novum Organum with ordinary atten-
tion, without carrying away an impression directly the reverse
of that of Bacon’s ignorance and disregard of the laws and li-
mits of the human understanding. ‘The first sentence of the
work contains an emphatic declaration of homage to these ve-
ry laws: Homo Nature minister et interpres, tantum facit et in-
telligit, quantum, de Nature ordine, re vel mente observaverit ;
nec amplius scit, aut potest. The grand lesson which it every
where inculcates is, that all false philosophy had sprung from
the too high notions hitherto entertained, of the powers of the
mind ; these notions having led to the disregard or contempt
of the only means by which true knowledge can be obtained.
Causa vero, et radix, fere omnium malorum in scientia ea una
est, quod dum mentis humane vires falso miramur et extolli-
mus, vera ejus aucilia non queramus. Bacon saw more clearly
than any preceding inquirer, the folly of supposing the mind ca-
pable of explaining the constitution of Nature by means of prin-
ciples of its own invention, and reasonings a priori ; and his
main aim in the Novum Organum was, to withdraw philoso-
phy from such airy speculations, and to employ it in a way more -
suitable to its purposes, and the limited nature of our faculties.
Employed in this way, that, namely, of inductive inquiry, he
showed that philosophy would greatly extend the compass of
our knowledge, and multiply the instruments of our power.
It is not, therefore, without good reason, that Mr Srewarr pa-
negyrizes the author of the Novum Organum, for his know-
ledge of “ the laws, limits and resources of the human un-
derstanding,” and for the general soundness of his views as to
the ends and rules of philosophical investigation.

The

oe

PHILOSOPHICAL WRITINGS OF LORD BACON. 381

ay

The truth is, that this writer is, after all, ‘constrained. to
make an admission, which of itself sufficiently proves the
groundlessness of his general censure of Bacon’s philoso-
phy. ‘“ That the rules of investigation which it lays down,
“ are wise and salutary with reference to physics, we are
“ happy,” says he, “ to admit*.” Now, the Novum Or-
ganum is almost wholly occupied with the exposition and
illustration of these very rules; and yet it is branded by
this writer with the imputation of manifesting disrespect “ in
“ every page” to the laws and limits of the understand-
ing, and a total ignorance of the purposes of science. It
would prove a rather perplexing task, I should imagine, to
show how any one could methodize a set of “ wise and sa-
“ Jutary rules of investigation with reference to: physics,”
who, yet, had no sound views of the nature. and: objects
of philosophical inquiry. There must either, in short, be
something in the nature of physics to take that great branch
of knowledge out of the general category. of philosophy, or it
must be absurd to say, that Bacon could unfold the true prin-
ciples of physical investigation, he being at the same time ig-
norant of the nature and aim of genuine science. His rules
with respect to physical inquiry were “ wise and salutary,”
precisely because they were conformable to the laws and limits
of the human understanding ; because “ he saw well,” to use
his own words, “ that the supposition of the too great suffi-
** eiency of man’s mind had lost the means thereof +.”

It is besides to be observed, that there is no ground whatever
for the limitation of the wisdom and utility of Bacon’s logical
precepts to the physical sciences alone. He who admits that

they,

* Quarterly Review, No. xxxiii. p. 52.

+ Filum Labyrinthi, Works, vol. i. p.. 400. 4to edit.

382 ON THE SCOPE AND INFLUENCE OF THE

they are “ wise and salutary with reference to physics,” must

goa step farther, and admit that they are also wise and salu-
tary with reference to inquiries regarding the mind. The ob-
ject of philosophy, and the principles of philosophizing are the
same, whether the investigation relates to the laws of matter
or the laws of mind ; and thus the logic of the Novum Organum
cannot be useful with reference to the one, without having the
same character with reference to the other. It is upon this
ground that Bacon himself represents his logic as equally ap-
plicable to the advancement of the moral and metaphysical as
of the physical sciences. ‘“ Atque quemadmodum vulgaris Lo-
“ gica, que regit res per Sy/logismum, non tantum ad naturales,
** sed ad omnes scientias pertinet; ita et nostra, que procedit
“ per Jnductionem, omnia complectitur *.”

In adverting to the question as to the influence of Bacon’s
philosophical writings upon the subsequent progress of phy-
sical science, this writer observes, that it presents a “ point
*“ as to which it is very difficult to form an explicit opi-
* nion. But this,’ says he, “ is sufficiently clear, that if Ba-
* con’ is to be allowed any considerable share in the honours
“ which modern experimentalists have acquired, he may, in
“ many respects, be compared to the husbandman in Aisop’s
“ fable; who, when he died, told his sons that he had left
“ them gold buried under ground in his vineyard; and they
“ digged all over the ground, and yet they found none; but by
“ yeason of their stirring and digging the mould about the
“ roots of their vines, they had a great vintage the following
“ year.” It would, if I do not mistake the matter, be as diffi-
cult to explain, how this simile could assist any one to form a
correct opinion upon the point in question, as to explain how

Bacon

* Novum Organum, Lib. i. Aph 127.

PHILOSOPHICAL WRITINGS OF LORD BACON. —- 883

Bacon could deliver a wise system of rules for the advance-
ment.of physics, without having any just notions of the true
nature of philosophical inquiry. ‘The object to which Bacon
directed the attention of his followers, was the very object he
was desirous they should accomplish,—the regeneration of
philosophy by means of a well-regulated use of observation
and experiment. The benefits, if any, which accrued to man-
kind from his. directions, were obtained precisely in the way,
and were precisely of the kind, which he pointed out and pro-
mised. Thus, the case of A‘sor’s husbandman is so far from
furnishing an illustration of Bacon’s connection with the ad-
vancement of physics, that there is evidently no ground what-
ever for such a parallel; and the writer who institutes it only
proves, that he has altogether mistaken the true bearings of the
question. But, before proceeding to state the proofs ‘of this
connection, it will be proper to show somewhat more fully,
that Bacon’s philosophical merit was of the highest kind, om
that. it was wholly unshared by any other person.

Bacon’s grand distinction, then, considered as an improver
of physics, lies in this, that he was the first who clearly and
fully pointed out the rules and safeguards of right reasoning
in physical inquiries. Many other philosophers, both an-
cient and modern, had referred to observation and: experi-
ment in a cursory way, as furnishing the materials of physi-
cal knowledge; but no one, before him, had attempted to
systematize the true method of discovery ; or to prove, that
the Inductive, is the only method by which the genuine of-
fice of philosophy can be exercised, and its genuine ends ac-
complished. It has sometimes been stated, that Ga itro
was, at least in an equal degree with Bacon, the father of the
Inductive Logic; but it would be more correct to say, that his

discoveries

7

384 ON THE SCOPE AND INFLUENCE OF THE

discoveries furnished some fortunate illustrations of its princi-
ples. To explain these principles was no object of his; nor
does he manifest any great anxiety to recommend their adoption,
with a view to the general improvement of science. The Ari-
stotelian disputant, in his celebrated Dialogues, is made fre-
quently to appeal to observation and experiment; but the in-
terlocutor through whom Gatitro himself speaks, nowhere

takes occasion to distinguish between the flimsy inductions of

the Stagyrite, in regard to the subjects in dispute, and those
which he himself had instituted ; or to hint at the very differ-
ent complexion which philosophy must assume, according as
the one kind or the other is resorted to. Thus, though Gaut-
LEO wasa great discoverer, it cannot be said that he had any
distinction from having taught the principles of the art by
which discoveries are made. That distinction belongs wholly
to Bacon. ‘No man,” says one of the most eminent of our
earlier philosophers, “ except the incomparable Veruiam, has
“ had any thoughts of an art for directing the mind in physi-
“ cal inquiries *.”

Some late writers have, elite advanced an opinion, that
this: distinction does not belong exclusively to any of the
moderns +. ‘“ It is an error,” we are told, “ to represent Bacon
“ as professing his principle of induction to be a discovery.
“ The method of induction, which is the art of discovery, was
“ so. far from being unknown to Anistot.e, that it was often
“ faithfully pursued by that great observer. What Bacon aim-
“ ed at; he accomplished; which was, not to discover new
“ principles, but to excite a new spirit, and to render observa-

“ tion

* Hooxe.—Posthumous Works, p. 6.

+ See some admirable remarks on this subject, in the second volume of Mr
Srewart’s Philosophy of the Mind, Chap. 4. sect. 2.—On the induction of Arts-
TOTLE compared with that of Bacon.

See: tS an ee ee ee

PHILOSOPHICAL WRITINGS OF LORD BACON. 385

** tion and experiment the predominant character of philoso-
phy *.” Itis withconsiderable diffidence that I dissent from
any statement made on the subject of Bacon’s philosophy by the
author of the splendid and instructive essay here referred to.
But I must be permitted to express some surprise, that Ae should
represent Bacon’s aims and labours as having been professedly
limited to the revival of a method of discovery which had
been well known to, and successfully practised by Anistorue.
Nothing can be more certain, than that Bacon rests the whole
hopes of his philosophy, upon the novelty of his logical pre-
cepts +; and that he uniformly represents the ancient philo-
sophers, particularly Arisrorie, as having been wholly re-
gardless of the inductive method in their physical inquiries.
Bacon does not, indeed, say, that the ancient philosophers ne-
ver employed themselves in observing Nature ; but.he main-
tains, that there is a wide difference between observation as
it was employed by them, and the art of observing for the
purposes of philosophical discovery. “ Alia enim est ratio
“ naturalis historize, que propter se confecta est ; alia ejus, quee
“ collecta est, ad informandum intellectum in ordine ad con-
“ dendam philosophiam }.” Bacon does not accuse AristTo-
Tir of having always reasoned without any reference to facts;
but he contends, that Aristorte has nowhere stated the rules
for aiding and regulating the understanding in the process of
discovery by means of facts ; and that the use which he has
made of them in his philosophy, is very different from the use
which is made of them in the philosophy of induction. “ Ille
“ enim prius decreverat, neque experientiam ad constituenda
Vou. VIII. P. IL 3C “ decreta

* Edinburgh Review, No. liti. p. 186.
+ Novum Organ. Lib. i. Aph. 82. 95. 97. 125.
+ Ibid. Lib. i. Aph. 98. :

386 ON THE SCOPE AND INFLUENCE OF THE

“ decreta et axiomata rite consuluit ; sed postquam pro arbi-
“ trio suo decrevisset, experientiam ad sua placita tortam cir-
“ cumducit, et captivam *.” It should always be recollected,
that Bacon’s call was not merely for observation and experi-
ment ; but for observation and experiment conducted accord-
ing to certain forms and rules ; which forms and rules were first
delineated by him, and constitute the body of the Inductive
Logic. There may be nothing im this logic that can be called
a discovery in the strict sense of the word ; but the statement
of its precepts, was certainly a grand and important step to-
wards the advancementofv2n uine science. ut
It would require a complete analysis of the Novum Organum.
to furnish an adequate idea of the value of Bacon’s services in
this important department of philosophy ; but the fundamental
rules of his method may be comprehended in a few sentences.
They seem all to be founded upon the following principles :
first, That it is the business of philosophy to. discover the laws.
or causes that operate in Nature, in order thereby to explain.
appearances, and produce new effects}: next, That we are
incapable of discovering these laws or causes in any other
way than by attending to the circumstances in which they
operate: and, lastly, That the mind is naturally disposed
to run into general conclusions, and to form systems, be-
fore

* Novum Organum, Lib. i, Aph. 63.

+ Novum Organ. Lib. i. Aph. 117. Throughout the whole of the first book,
the object of science is represented to. be the discovery of Axioms ; by which term
Bacon eyidently means those general laws or truths which form the basis of our
physical reasonings. Newron, as Mr Srewanrt observes, has, after Bacon’s ex-
ample, applied the term Axtom to the laws of motion, and to. the statement of
certain general truths in Catoptrics and Dioptrics. See Philosophy of the Mind,
vol. ii. Chap. 4. They who are engaged in the study of the Novum Organum,
will derive much valuable information and assistance from the perusal of this
part of Mr Srewarr’s work.

PHILOSOPHICAL WRITINGS OF LORD BACON, 387

fore having made all the inquiries necessary to truth. In confor-
mity with these principles, he shows, that all sound philoso-
phy must proceed from facts; that the facts in every case
must be carefully collected and compared ; and that in all our
reasonings about them, the natural tendency of the mind to
generalize must be carefully repressed. The spurious method
of induction is that which proceeds suddenly from particulars
scantily collected or ill examined to the most general conclu-
sions. The érue method is that which lays a wide basis in ob-
servations and experiments, and which generalizes slowly ; ad-
vancing gradually from particulars to generals, from what is
less general to what is more general, till the inquiry énds in
truths that appear to be universal *.

_ Nothing could be more encouraging or animating, than Ba-
con’s recommendations of this plan of inquiry. Though
he held that the noblest end of philosophy is the discove-
ry of truth}, he taught that there is a correspondence be-
tween this and another end, also of great dignity,—the im-
provement of the outward accommodations of human life. He
showed, that, when the principles of science should really be
derived from the knowledge of Nature, their discovery would
prove beneficial to man, as well in respect to the increase of his
power as of his knowledge ; because the ptinciples so discovered
would lead to new inventions in the useful arts, and to new rules
for the improvement of all the operative parts of knowledge.
He endeavoured to stimulate the spirit of inquiry, by represent-
ing the field of scientific discovery, as yet almost wholly uncul-

B.C 2). tivated

* Nov. Organ. Lib. i. Aph. 100, 101, 102, 103, 104, 105.

+ Ibid. Aph. 124. 129. He takes some pains here and elsewhere to guard
against the supposition that he valued science only as it was calculated to aug-
ment the outward accommodations of life.

388 ON THE SCOPE AND INFLUENCE OF THE

tivated, and by assurances that it only required to be cultivated’
with attention to his rules, in order to yield an endless increase:
of knowledge and of inventions. “ Let it be believed,” says he,
and appeal thereof made to time, with renunciation, never=
theless, to all the vain and abusing promises of the Alchy-
mists, and such like credulous and fantastical sects, that the
new found world of land was not greater addition to the old;
than there remaineth at this day a world of Inventions and’
Sciences unknown, having respect to. those that are known,
with this difference, that the ancient regions of knowledge
will seem as barbarous compared to the new, as the new re-
gions of people seem barbarous compared to many of the
“ old *.” It is in these confident anticipations of the future
triumphs of science, so often repeated as encouragements to its.
faithful prosecution, that we more particularly perceive the
grandeur and reach of his views. His predictions of improve-
ment were not the vague or casual surmises of a happy enthu-

siasm; they were evidently grounded upon an enlightened

conviction, that the business of philosophy had. hitherto beer
mistaken, and that her labours would prosper, when they:
should be employed with. constancy and. skill upon their legi~
timate objects.

Is it not unreasonable to doubt the utility of a system of
logical instructions, in which the true art of discovery was,
for the first time, explained? These instructions were of
fered at a period in every respect opportune: There was a
growing disposition to revolt against the Schools, and: a wise
leader was wanted to raise the true standard of reform, and to
give a salutary direction to the pursuits of those who should
emancipate themselves from their authority. The improve-

ment

ee

* Of the Interpretation of Nature, Chap. ii—Works, vol. i. p. 376. 4to edit.

=

eer

-

_ eet

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PHILOSOPHICAL WRITINGS OF LORD BACON. 389:

ment of some branches of physics was already in part begun ;
but there was no general agreement as to the rules of inquiry.:
The truths which Bacon taught are now, it is true, known,
and their authority acknowledged by all; but this was far
from. being the case in the early part of the seventeenth
century. One of the most intelligent of his friends, Sir Tuo-
mas Boprey, to whose judgment he submitted an early sketclr
ef his plan, appears to have been. wholly unable to. distin-
guish between the loose procedure of the: Empirics and that
regulated procedure which it recommends. ‘ As for that,”
says he, “‘ which you inculcate of a knowledge more excellent
“ than. now is among us, which experience might produce;
“if we would but essay to extract it. out of Nature by particu-
‘« lar probations; it cannot, in reason, be: otherwise thought,
“« but that there are infinite numbers which embrace. the course
“that you propose, with all the diligence and care that ability can
“ perform. I stand well assured,’ he concludes, “ that tor the
“ tenor and subject of your main. discourse, you. will not be
“able to impannel. a. substantial: jury in any university,. that
“ will give up a verdict to acquit you: of error*.” But that
which places the importance of Bacon’s logical instructions in
the strongest light, is the fact, that one of the most celebrated
of his contemporaries, who also professed himself a reformer of.
philosophy, employed the better part of his life, in teaching

doctrines as diametrically. opposite in principle as in tendency.
‘This. was Descarrss. ‘“ Never,” says an eloquent philosopher,
“did two men, gifted with such genius, recommend paths of in-

“ quiry so widely. different.. Descartes aspired to deduce an ex-

“. planation of the whole system of things by reasoning a priori

“ upon

* Sir Tuomas Boptey’s Letter to Sir Francis Bacon aut his coGiTaTA ET:
visa.—Bacon’s Works, vol. iii. p. 242, 243, 244,

390 ’ ON THE SCOPE AND INFLUENCE OF THE

5
.

upon assumed principles: Bacon, on the contrary, held, that
“ it was necessary to observe Nature thoroughly before at-
“ tempting to explain her ways; that we must ascend to prin-
“ ciples through the medium of facts ; and that our conclu-
“ sions must be warranted by what we observe. Descarres
“ reasoned about the World, as if the laws which govern it had
“ not yet been established, as if every thing were still to
“ create. Bacon considered it as a vast edifice, which it was
“ necessary to view in all directions, to explore through all its
“ recesses and windings, before any conjecture even, could be
“ safely formed as to the principles of its construction, or
“ the foundations on which it rests. Thus, the philosophy of
“ Bacon, by recommending the careful observation of Nature,
« still continues to be followed, whilst that of Descarres,
«« whose essence lay in hypothesis, has wholly disappeared *”
Nor was Descartes, I may add, ignorant of what Bacon had
taught as to the principles of philosophizing. It appears, on the
contrary, from his correspondence, that he was well acquaint-
ed with Bacon’s writings ; and, in one of his letters, he seems
to admit, that provided the Experimental were the true Me-
thod, there was nothing that could be added to increase the
utility of Bacow’s precepts f.

Having made these remarks, with a view to point out, in a ge-
neral way, the nature and importance of those helps and encou-
yagements which Bacon’s writings furnished to physical inqui-
ry, Lam next to endeavour to show, that the subsequent pro-
gress of physical knowledge was greatly accelerated by the ef-
fects which they produced. And here I beg to observe,

that
2

* Baitiy.—Histoire de ? Astronomie Moderne, tom. ii, Tiv. 4. § 2.

+ Lettres de M. Descartes, tom. iv. p. 201, Paris edit. 1724.

a ee

ae a

PHILOSOPHICAL WRITINGS OF LORD BACON. 391

that I have no argument with those who hold, that the re-
formation of philosophy by the adoption of the Inductive
Method would have taken place in time, though Bacon had
never written; any more than with those who hold, that physical
science owes nothing to him, on the score of any discovery of
importance made by himself, or deduced by others from his sug-
gestions. I have before stated, that this reformation was al-
ready in progress, and that the Inductive Method had been
happily ewemplified in the discoveries of some of his contem-
poraries. The proposition here maintained is, that Bacon
did more to forward its general adoption than any other per-
son; and this,—because his writings contributed more than
the labours of any other individual, to complete the abandon-
ment of the scholastic methods and systems,—to generate a re-
lish for experimental inquiries,—and to imbue the minds of
the ingenious with the views and principles requisite to conduct
these inquiries with suecess. The way to prove that Bacon’s
writings were powerful agents in the advancement of physical
knowledge, is to prove that they produced: these effects; and
the proof that such effects were actually produced by them,
must necessarily be derived from the testimony of thee who
early experienced, or became otherwise acquainted with their
operation.

_ The reputation which Bacon had acquired from his Essays, a
work early translated into various foreign languages; his splendid
talents as an orator, and his prominent place in public life,—
were circumstances strongly calculated to attract the curiosity
of the learned world to his Philosophical Writings ; and from
some of which, he derived advantages in regard to their circu-
lation, not possessed in that age by ordinary men. These wri-

_ tings accordingly appear to have been early read by the learn-

ed at home, and early transmitted to the learned abroad ; and
it

392 ON THE SCOPE AND INFLUENCE OF THE

it farther appears, that the important truths which they disclo-
sed did not remain long unperceived, or barren of consequen-
ces. ‘* Dr Coxuins, Provost of King’s College, Cambridge,
“ a man of no vulgar wit, affirmed unto me,” says Bacon’s
Chaplain, Dr Rawxey, “ that after reading the Advancement of
“ Learning, he found himself in a case to begin his studies
“ anew, and that he had lost all the time of his studying be-
“ fore *.” Of his more recondite work, his distinguished con-
temporary Ben Jounson speaks ag follows: “ The Novum
“ Organum is not penetrated or understood by superficial men,
“ who cannot get beyond Nominals, but it really openeth all
“ defects of knowledge whatsoever ; and is a book

«* Qui longum noto Scriptori proroget vum *.”

Sir Henry Worron, another of the most eminent men of that
day, thus warmly expresses his opinion of its merits: “I have
“ received,” says he, in a letter to Bacon, written from Ger-
“ many, three copies of that work, wherewith your Lordship
“ hath done a great and everlasting benefit to all the children of
“ Nature, and to Nature herself in her utmost extent and lati-
“ tude,who never before had se true an Interpreter, or so inward
“ a Secretary of her Cabinet f.” In this letter, Sir Henry gives
an interesting account of an accidental meeting which he had
lately had with the celebrated Kepier, in Upper Austria; to
whom, he adds, he was about to send one of his copies of the No-
vum Organum, for the honour of England. It is not surprising,
that a writer who entertained such sentiments in regard to the

importance

* Life of Bacon, prefixed to Raw ey’s Resuscitatio, or bringing to light seve-
ral pieces of the Works of Lord Bacon.

+ Ben Jonson’s Discoveries.— Works, vol. vii. p. 100. Wxattey’s edition.

+ Reliquie Wottoniana, p. 299. 3d edition.

PHILOSOPHICAL WRITINGS OF LORD BACON. 393

importance of Bacon’s Philosophy, should have been led to
predict the speedy downfal of that of the Schools. “ Sir Henry
“ Worron,” says Dr Beate, in a letter to Mr Boy gz, written
about forty years after this period, “ would often please him-
“ self in lashing the Schoolmen; and would often declare it
“ as a serious prediction, that in ¢his age their reputation
** would yield to more solid philosophy.” Dr Beare adds,
that he had himself been weaned.from the errors of the Schools,
by the early perusal of Bacon’s philosophical writings *.

In a letter to King James, written about the period of
the publication of the Novum Organum, Bacon states, that
the Advancement of Learning, had been very favourably
received in the Universities; and he thence draws the con-
clusion, that the Novum Organum would also be acceptable
to them; because, says he, “ it is only the same argument
“ sunk deeper f.”. In an address presented to him by the
University of Oxford, in the year 1623, he is represent-
ed.as a “mighty Hercures, who had by his own hand
“ greatly advanced those pillars in the learned world, which,
“by the rest of the world, were supposed immoveable + ;”
and this piece of homage, it is to be observed, was offer-
ed at a time when all motives to interested adulation had
been done away by his lamentable fall. These facts seem to
evince, that Bacon’s writings had earlymade a strong impression,
even in quarters where favourable effects were not likely to
be speedily produced; and accordingly, we are informed by
. Vox. VIII. P, I. Satven BD ‘ Bishop

eee eee eee

* Boyue’s Works, vol. vi. p. 355. :

+ Bacon’s Works, vol. iii. p. 584.

+ Tennison’s Baconiana, or certain Genuine Remains of Sir Francis Bacon,
p- 206.

394 ON THE SCOPE AND INFLUENCE OF THE

Bishop Sprat, that when some of those ingenious men who
afterwards assisted in forming the Royal Society, began, about
the end of the Civil War, to establish a weekly meeting at
Oxford for philosophical discussion, they found, that the new
spirit of “ free inquiry” had already made considerable pro-
gress among the members of the University *.

When one’of Bacon’s friends asked him, Whether he thought
the Churchmen likely to oppose his intended reformation of
philosophy, his answer was—“ I have no occasion to meet
“ them in my way, except it be, as they will needs confede-
“ rate with AristorteE, who, you know, is intemperately
“ magnified by the School-Divines +.” We are told by Os-
BORN, a contemporary observer, that the “ School-Divines” did
endeavour to cry down his philosophical writings, by represent-
ing them as favouring atheism {. This was their usual mode
of warfare when the established tenets of the Schools were at-
tacked by any formidable patent The Aristotelians of all

descriptions,

* Sprat’s History of the Royal Society, p. 53 ; also p. 328. This spirit
} appears to have made still greater progress at Cambridge. Gutanvitt, who
became a student of Exeter College, Oxford, in 1652, ‘* lamented,” says
Antnony Woop, ‘ that his friends did not, send him to, Cambridge; because,
he used to say, that the new philosophy, and the art of philosophizing, were
more cultivated there, than here at Oxford.”—Athen. Oxon. vol. ii. p. 662.
—« After the way of free-thinking,” says Baxer, “ had been laid open by
Lord Bacon, it was soon after greedily followed.” See his Reflections on Learn-
ing. This work was first published in 1699. The author, who was a Fellow of
St John’s College, Cambridge, was deeply read in the history of that University.
His extensive collections upon that subject are deposited in the British Mu-
seum.

+ Bacon’s Letters to Sir Tosy Marraew, in his Works, vol. iii, p. 247, 257.

+ Introduction to Oszorn’s Miscellany of Essays, Paradoxes, and Discourses.”

ee!

ogee

PHILOSOPHICAL WRITINGS OF LORD BACON. 395
descriptions, appear to have early manifested a decided hosti-
lity to his philosophy ; and their criticisms are sometimes ex-
pressed in a way which plainly testifies that it had made con-
siderable progress. The examination of his Sy/va Sylvarum, by
ALExaNDER Ross, now much better known by Burten’s sarcas-
tic allusion in the poem of Hudibras, than by any of his own
multifarious productions, furnishes a curious example. It was
published in the year 1652, that is, about twenty-five years after
Bacon’s death. .“ I have,” says he, “ cursorily run over my
** Lord Bacon’s New Philosophy, and find that philosophy is
“ like wine, the older the better. For, whereas ArisroTLe
“ had, with infinite pains and. industry, and not without. sin-
“* cular dexterity, reduced all entities into certain heads, and
*- placed them in ten classes or predicaments. to, avoid confu-
“ sion, and that we might, with the more facility, find out. the
“ true genus and difference of things; which. Aristotelian
‘* way hath been received and approved by all, Universities,
*“ and the wise men since his time in all ages, as being the
* most consonant to reason: yet these New Philosophers, as if
“* they were wiser than all the world besides, have, like fantastic
“ travellers, left the old beaten path, to find out ways unknown,
“and have reduced his comely order, into chaos; jumbling
“ the predicaments so together, that their splisthcsioe can never
“ find out the true genus of things.” The examples which
he adduces in illustration of this disorder, are in fact proofs
of the growing taste for experimental inquiry ; and it is clear
from the context of the whole passage, that Bacon was consi-

dered by the Aristotelians as having been its chief promoter.

“‘ Sometimes,” he continues, “these New Philosophers tell us,
“ that heat, cold, &c. are spirits, consequently substances ;
“ sometimes, again, they will have them to be qualities ; some-
* times to be motions and actions. Thus, Proteus-like, they

3D ny “ turn

596 ON THE SCOPE AND INFLUENCE OF THE
* turn themselves into all shapes, so that we know not in what
“ predicament to put their heat, or what genus to give it *.”
That New Philosophy, which had already produced so muclt
embarrassment among the followers of Aristorter, had already
also led to the formation of a Philosophical Society, destined,
at no distant day, to realize, in some sort, one of Bacon’s
favourite projects. In his letter to King James, written on the
publication of the Novum Organum, he states, that his chief
object in publishing the work, before completing'it according
to his original plan, was, to try to procure help towards com-
piling an “ experimental history of Nature fT.” He more than
once alludes, in the work itself, to the great things that might be
accomplished in philosophical inquiries, by a conjunction of Ja-
bours ; and in a romantic piece, called the New Atlantis, he gives
an account of a feigned College or Society, magnificently endow-
ed, and whose business was the improvement of all the depart-
ments of physical knowledge. To this College he gives the
name of Solomon’s House. The intention of this piece evidently
was, to exhibit a grand and alluring representation of the ad-
vantages that might be derived from the co-operation of num-
bers in scientific pursuits, and of the renown that a Prince might
acquire by forming an establishment directed to such purposes.
These views and schemes were not forgotten by his followers.
in the year 1645, a Society was formed in London, for the pur-
pose of discussing subjects connected with Natural Philosophy,
at. stated weekly meetings ; and the name first given to this So-
ciety appears to have been that of the Philosophical College t.
Some

* Ross’s Arcana Microcosmi, or the hid secrets of Man’s body discovered ;
with a refutation of Lord Bacon’s Natural History, p. 263, 264.

‘+ Bacen’s Works, vol. iii p. 584.

+ See Boyte’s Life, prefixed to his Works, p. 34. This Society was some-
times called the Invistble College.—Ibid. p 40. 42.

PHILOSOPHICAL WRITINGS OF LORD BACON. 397

Some of its members being soon thereafter appointed to Profes-
sorships in the University of Oxford, a similar Society was
established. by them in that place. In the year 1659, the prin-
cipal members of the Oxford branch having returned. to, Lon-
don, the two Societies were united ; and hese on the Resto-
ration, extended their views to the obtaining a public esta-
blishment, they, in. 1662, succeeded in accomplishing that ob-
ject, by being erected into a corporate body, under the title of

the Royal Society. Wy
There can be no doubt Pe aerate of the influence pe Bacon’s
suggestions, as to the utility of such an institution, upon the
minds of those who planned the establishment of this illus-
trious Society... Its earliest. panegyrists and historians bear, tes-
timony to this fact. ‘“ Solomon’s House, in the New Ailantis, was
“ a prophetic scheme of the Royal Society.” »These are the
words of GuanviL1, in his address to that body, prefixed to, his
Scepsis Scientifica, published in 1665*, . Bishop Srrar, whose
ik? Pe reave / , . »History.,

' DD ae e188 |

* ‘The Sepsis Seientifiea i is a republication, with some: adidion of : Guan-
vitt's first philosophical work, The Vanity of Dogmatizing, ' published i in 1661.
The 20th chapter of this work contains a very distinct statement of the import-
ant doctrine so often ascribed to Mr Hume,—that we never percedve causation in
the succession of physical events ; a-déoctrine which fixes the object of ‘physical
science to be, not’ the inyestigation of the efficient causes of phenomena, but of
the general laws by which they are regulated; and for which statement of its le-
gitimate objects, it is always to be remembered, that physics is indebted to meta-
physics. The Aristotelians were provoked by the free spirit of inquiry, and‘
disregard of the authority of their Master, wliich kis work disclosed ;- and an
answer to it appeared in 1663, in a book entitled Sczrz, stve Sceptices et ‘Sceptico- .
rum a@ jure disputationis exclusio. 'The author was Tuomas Axsius, (Wuite),
a secular priest of the Romish Church, and a noted Aristotelian. ‘ Hosses,”
says A. Woop, “ hada great respect for Waite, and when he lived in W est-
minster, he would often visit him, and he Honses; but they seldom parted in
cool blood: for they would wrangle, squabble and scold about. philosophical
matters like young sophisters, though either of them was eighty years of age.

Howses

398 ON THE SCOPE AND INFLUENCE OF THE

History of the Society, published in 1667, received its public.

sanction, expresses himself as follows: “* The Royal Society
““ was a work well becoming the largeness of Bacon’s wit to
** devise, and the greatness of CLarENvon’s prudence to esta-
“ blish *.” Sprar also informs us, that the Tract published
in 1661, by Cowxery, entitled, A Proposition for the Advancement
of Experimental Philosophy, “ very much hastened the contri-
“* vance of the platform of the Royal Society ;” and this Tract
bears internal evidence that its author’s views were originally
derived from the New Atlantis.

But it is of more importance to show, that the philosophical
spirit which actuated the founders of this institution, was chiefly
owing to the effects produced by Bacon’s writings. And here,
again, I must appeal, in the first place, to the testimony of those
to whom. we are indebted for all that we know of its early
history. The fullest account of its origin is given by the cele-
brated mathematician Dr Joan Wattts, who was one of those
who instituted the weekly meetings begun to be held in London
in 1645; and his narrative distinctly points to Bacon, as having
given a beginning to the taste for experimental science in Eng-
land. ‘ Our business,” says he, “ was to discourse and consi-
“ der of things appertaining to what hath been called the New
“ Philosophy, which, from the times of Gatixo, and Lord
“ Veruzam, hath been much cultivated abroad, as well as

with

Hoszes being obstinate, and not able to bear contradiction, those who were
sometimes present at their wrangling disputes, held that the laurel was carried
away by Wurre.”—Athene Oxon. vol. ii. p 665. The Scepsis Scientifica has,
appended to it, a reply to the animadversions contained in Wuire’s Scirt upon
the Vanity of Dogmatizing.

* History of the Royal Society, p. 144. Copies of this work were sent, by
the Society, to foreign Princes, and other eminent persons abroad, in order to
furnish them with an authentic account of its history. See Dr Bircn’s History
of the Royal Society, vol. ii. p. 207.

\

ce mat

ORIEL SO

ee ee

—

i 2

PHILOSOPHICAL WRITINGS OF LORD BACON. 399

* with us in England*.” Sprar always speaks of Lord
Bacon, as the founder of that experimental school, which
came to be embodied in the institution whose history he
wrote + ; and the testimony of Mr Oxpensure, its first Secre-
tary, though a foreigner, is equally explicit. “ The enrich-
“ ment of the storehouse of Natural Philosophy, was a work,”
says he, “ begun by the single care and conduct of the ex-
“cellent Lord Verutam, and is now prosecuted by the joint
“ undertakings of the Royal Society t.” Guanvint, whose
zeal in defending this establishment, against the attacks of its
enemies, well entitles him to respectful notice in the history of
philosophy, makes frequent acknowledgements to the same
purpose. The following passage contained in the work which
he wrote in its defence, and which was published in 1668, under
the title of Plus ultra, or, the Advancement of Knowledge since the
days of AxistorLe, is too remarkable to be omitted on the pre-
sent occasion. “The philosophy that must signify either for light
** or use, must not be the work of the mind turned in upon itself,
“ and only conversing with its own ideas; but must be rai-
* sed from’ the observations and ae of sense, and

47 : “ take

* See his Account of his own Life, in a Letter published in the Appendix to
Hearne’s Preface to Lanetort’s. Chronicle, Number IX. ft
+ See particularly p. 35. History of the Royal Society.

+ Philosophical Transactions, No. 22. p. 391. Mr O.peneurc frequently
alludes to Bacon as the chief forwarder of experimental philosophy. ‘ When
our renowned Lord Bacon had demonstrated the methods for a perfect restora-
tion of all parts of real knowledge, the success became on a sudden stupendous,
and effective philosophy began to sparkle, and even to flow into beams of bright
shining light all over the world.”—Pref. to Philosophical Transactions tor 1672.
—** Many of the chief Unversities in Christendom have formed themselves into _
philosophical societies, and have largely contributed their aids to advance Lord
Bacon’s design for the instauration of arts and sciences.”—Pref. to Philosophical
Transactions for 1677.

400 ‘ON THE SCOPE AND INFLUENCE OF THE

“ take its accounts from things as they are in the sensible
* world. The illustrious Lord Bacon hath noted it as the
“ chief cause of the unfruitfulness of the former methods of
“ knowledge, that they were but the exercisés of the mind
“ making conclusions, and spinning out notions from its own
“ native store ; from which way of proceeding nothing but dis-
“ pute could be expected *—He therefore propesed another
“ method, which was, to reform and enlarge knowledge by ob-
“ servation and experiment ; to examine and record particu-
“ Jars; and to rise by degrees of induction to general :proposi-
“ tions ; and from them to take observation for new inquiries ;
“ so that nature being known, may be mastered, and used in
“.the service of human life. This was a mighty design,
“ groundedly laid, and happily recommended by the glorious
“ author; but to the carrying it on, it was necessary there
“ should be many heads and many hands, and those form-
“ ed into an assembly that might inter-communicate their
“ trials and observations. This the great man desired, and
“ formed a Society of experimenters in a romantic model ;
“ but he could dono more ; his time was not ripe for such per-
“ formances. These things, therefore, were considered by the
“ later Virtuosi, who several of them combined together, and
“ set themselves to work upon his grand design +.”

s

.

Similar

* Guanvitx’s Plus Ultra, p. 52.

+ Ibid. p. 87, 88.—There are some who would fain persuade us, that the
taste for experimental philosophy was introduced into England from the Conti-
nent, and that the first idea of the Royal Society was copied from similar asso-
ciations abroad. This, certainly, was not the language of the founders and early
historians of that Society. It is curious to remark, that while some of our
own writers ascribe its origin, and the philosophical spirit which gave it birth,
to foreign excitements, there are, on the other hand, foreign writers who trace
the Academies of the Continent to the effects produced by the writings

of

PHILOSOPHICAL WRITINGS OF LORD BACON. 401

_ Similar testimonies occur in many other publications of that
day ; in the more obscure as well as the more noted. Indeed,
there is no room whatever for doubt, that Bacon was generally
considered as the chief promoter of genuine physics, at a pe-
riod when the erection of the Royal Society, was of course
"likely to bring forward. the name of any individual, whose la-
bours had contributed, in a remarkable degree, to foster the
growth of physical science., Cow ey, surely, will not be re-
jected as an evidence of the general sentiment, merely be-
cause he has recorded his testimony in verse. He was, as al-
ready mentioned, a zealous advocate for a public institution,
directed to the purposes of experimental philosophy ; and, on
the establishment of the Royal Society, he addressed to it that
celebrated Ode in which he represents Bacon as its Legislator.
Dr Heynry Power calls Bacon “ the Patriarch of experimental
“ philosophy ;” in a work published in 1664, in which he de-

Vou. VIL. PLT. - BiBndy vids tails ©

of Bacon. The following passage is extracted from a very learned History of one
of the earliest of these Academies.—*+ Sed, quz superest dicenda, supremam, et,
ut nobis videtur, proximam condende Academiz enarrabimus occasionem. Scili-
cet postquam, ineunte circiter priori seculo, non inter Britannos solum, sed universi
quoque orbis incolas, immortalitati commendatissimus, Franciscus Baco de Ve-
rulamio, supremus regni Britannici Cancellarius, variis jisque ad sapientiz normam
elucubratissimis scriptis, utilissima emendande atque instaurandz historiz natu-
ralis dedisset consilia, et absolutissimis rationibus firmasset : non Angli modo haud
tncassum se monert atque excitart passt sunt, sed exter quoque gentes, imprimis Galli
Italique, sanioris consilii patientes, tanta contentione cum qualibuscunque scientiis
generatim, tum przcipue rerum naturalium studio animum intenderunt, adeo,
ut ex illo tempore visi sint homines nihil, vel remotissimis naturz visceribus ab-
strusum, quod non captis ex Baconis mente experimentis curiosius rimarentur,
relicturi. Atque hic ardor, hac studia magnam quoque partem condiderunt Acade-
miarum Soctetatumque hactenus memoratarum.” Bucuners, Academ. Nature Cu-
wiosor. Hist. cap. i. § Ts

402 ON THE SCOPE AND INFLUENCE OF THE

tails the discoveries of Gatmero, Torricent1, and Pascat *.
“ It is certain,” says Mr Havers, in the preface to a work
also published in that year, entitled, Philosophical Conferences,
“ that Lord Bacon’s way of experiment, as now prosecuted
“ by sundry English gentlemen, affords more probabilities of
** glorious and profitable fruits, than the attempts of any other
** age or nation whatsoever t.”” Dr Josnua Cuiwprey, in the
introduction to his Natural Rarities of England, a book of the
same period, and which gave rise to a new class of publica-
tions in Natural History, states, that he had given it the title of
Britannia Baconica, in order to indicate its connection with those
studies which Bacon had originated {. Anruony Woop has pre=
served a letter from the same person to Mr OLpEnzvre, Secreta-
ry of the Royal Society, in which he says, that he had long been
engaged in the philosophical inquiries “ which form the busi-
“* ness of that body; in consequence of having fallen in love with
“‘ Lord Bacon’s Philosophy as early as the year 1646 ||.” Mr
Evezyn, one of the most active and respected of the early mem-
bers of the Society, has, in several of his works, alluded to the
beneficial effects produced by Bacon’s philosophical writings.
In: the introduction to his Sylva, which work he published
in 1664, at the request of the Royal Society, he takes oc-
casion to state the philosophical principles by which it profes-
sed to be guided, in terms which clearly point to the quarter
from whence they were derived. ‘“ They are not hasty,” says
he, “ in pronouncing from a single or incompetent number of

“ experiments ;

* Power’s Experimental Philosphy, p. 82.

+ Philosophical Conferences, translated from the French, by G. Havers, in
two volumes folio. .

+ Britannia Baconica, or the Natural Rarities of England, 1661, 8vo. ‘ From
this work,” says A. Woop, “ Dr Pror took the hint of his Natural History of
Oxfordshire.”

\| Athen@ Oxonienses, vol, ii, p. 468.

Saal

al

PREYS CEI

en'

oe Ia

>

ele

—

PHILOSOPHICAL WRITINGS OF LORD BACON. 403

“ experiments ; but after the most diligent scrutiny, and by
« degrees, and by wary inductions faithfully made, they re-
“ cord the truth and event of trials, and transmit them to po-
“ sterity. They resort not immediately to general proposi-
tions upon every specious appearance ; but seek light and in-

.* formation from particulars, that they may gradually advance

“ to general rules and maxims.” In an after work, he speaks
of Bacon’s services in the following expressive terms: “ By
“ standing up against the Dogmatists, he emancipated and set
“ free philosophy ; which. had long been a miserable cap-
“ tive; and which hath ever since bide conquests in the ter-
“ ritories of Nature *.”

It was about this period, that Mr Boye was honoured with
the appellation of the second Bacon +, in: compliment to his
exertions to advance the knowledge of experimental physics ;
and there can be no doubt, that his discoveries and exertions
did contribute essentially to establish the credit of the Eng-
lish School. Neither can there be any doubt, as to the influ-
ence of Bacon’s writings in determining the nature and objects
of his philosophical pursuits. This is admitted, or implied, in
many parts of his works f. It is clear, indeed, that he was
considered by his contemporaries as a marked disciple of Ba-
con. “ You have,” says Dr Beatr, in one of his letters
to him, upon the subject of his discoveries, “ particularised,
“* explicated, and exemplified, those fair encouragements, and
“ affectionate directions, which Lord Bacon in a wide generali-

8 E 2 cert

* Evetyn’s Numismata.

~ + See Guanviux’s Plus Ultra, p. 57.

{ Boyze’s Works, vol. i. p. 305, 6.; vol. ii. p. 472. ; vol. iii. p. 422.; vol. ix.
p. 59, 246.; vol. v. p. 567.

404 ON THE SCOPE AND INFLUENCE OF THE

“ ty proposed *.” Tn another letter, to Mr Hartrrs, who like
himself was an early and zealous promoter of the Royal Socie-
ty, Dr Beare thus rapturously expresses his feeling of the plea-
sure which Boyie’s experimental labours were calculated to
afford to the followers of Lord Bacon. “ To those that have
“ been tired and wearied, as I have been in the several ways
‘ of former philosophers ; to those who have condescended to
* take deep notice of the insufficiency of conjectures, and un-
“‘ grounded ratiocinations, and who have submitted their pa-
“ tience to the severity of Lord Bacon’s inquisitions, here are
‘ offered such pleasing refreshments, as give us the relish of
‘ that Virgilian simplicity, which was so highly admired by
“* ScanicER in these verses :

o

«

ral

cal

‘¢ Tale tuum carmen nobis, divine poéta,
«* Quale sopor fessis in gramine, quale per estum
* Dulcis aque saliente sitim restinguere rivo +.”

They who have overlooked or disregarded the proofs of the
connection between what Bacon enjoined, and Boye perform-
ed, are not likely to have recognized any traces of the lights
held out by the former, in the philosophy of Newron. Yet it
appears undeniable, that the latter was guided by principles
which Bacon alone had taught; and that his philosophy derives
its imperishable character from his rigid adherence to them.
To begin with the examination and comparison of phenomena
in order to rise to the knowledge of general truths, and to pro-

ceed

* Boyue’s Works, vol. vi. p. 405.

+ This letter is printed in the Life of Boruer, prefixed to his. works, p. 63.— Dr
Beate was elected a Fellow of the Royal Society in 1662. Several of his papers
are printed in the Transactions. He was a man of excellent parts, and great
public spirit; and the character which his friend Mr Harri gave of him was,
that there was no man in the island who could be made more universally use-
ful."—Bircn’s Hist. of the Royal Society, vol. iv. p, 235.

SO pe ean

PHILOSOPHICAL WRITINGS OF LORD BACON. 405

ceed gradually from truth to truth, till we reach the most ge-
neral that can be discovered,—these are the principles of phi-
losophizing which. Bacon unfolded, and which Newron has,
in the most emphatic terms, embodied with his discove-
ries. * Quel témoignage,” exclaims an eminent French philoso-
pher, “ rendu par le génie inventeur au génie des méthodes* !”
Such, indeed, was the connection between the logic of the No-
vum Organum, and the philosophy of the Principia, that it was
only where the one was followed, that the other prevailed.
The sublime Geometry of the Principia, says Mact.aurin, was
admired by all, but it was only among minds trained by Ba-
con’s. precepts that it found a ready reception for its Philo-
sophy +}.

To these proofs of the influence of Bacon’s precepts and
exhortations, reflected in the acknowledgments, the views, and
the discoveries of the early founders of the English School: of
Experimental Philosophy, I have yet to add those which are
furnished by the writings of its opponents and detractors. The
public countenance given to that School by the erection of
the Royal Society, early excited an extraordinary degree of
jealousy on the part of the Universities; and a keen spirit.
of opposition among the remaining supporters of the Aris-
totelian philosophy. Sprar accordingly found it necessary,
in his History of the Society, to employ a long argument to
_ prove, that this new establishment would be attended with

ar fom iy we

* Deceranno— Hisloire comparée des. Systemes de Philosophie, tom: i. p.396.—
The introduction to Dr Pemperton’s Account of Newton's Discoveries, a work,
‘< the greater. part of which was read and approved,” as we are told inthe preface,
by Newton himself, contains a summary of the doctrines of the Novum Organum ;
and its author is represented as the first who taught those rules of philosophizing
which Newton followed, and which his discoveries so nobly eonfirmed.

+ Mactavrin’s Account of Newton’s Discoveries, p. 59, 60.

406 ON THE SCOPE AND INFLUENCE OF THE

no bad consequences either to religion, or to the existing se-
minaries of knowledge. Guanvitt was obliged to enter into
a serious refutation of an assertion, that “ ArisrorLE had had
“ more advantages for knowledge than the Royal Society, ei-
“ ther had, or could have*.” ‘The panegyrics which these
writers bestowed upon the Institution, and upon Lord Bacon
as its Master, appear to have filled the followers of AristoTLE
with a still more envenomed hate to both. The most forward
of their champions was Dr Henry Stusse, who, after study-
ing at Oxford, had served for some time in Scotland with the
Army of the Parliament; but having on the Restoration made
his peace with the Government, he was appointed King’s
Physician for the Island of Jamaica, from whence he had late-
ly returned, to practise in his own country. He was, according
to Antuony Woop, “ the most noted Latinist and Grecian of
“ his age, and a singular Mathematician ;” but he seems to
have been as deficient in judgment as he was violent in temper ;
which last defect, his biographer 1 in great simplicity ascribes to
his “carrot-coloured hair +.” His publications against the Royal
Society, and the whole body of Eenermientatines, were nume-
rous,

_—

* « L desire the reader to know, that after Mr Josers Guanvitt had writ-
»ten certain things against Aristorie, it was the desire of some scholars, that
Rosert Crosse, a noted philosopher after the ancient way, should be brought
acquainted with him. In 1667, Guanvitt was therefore conducted to his
house, where Crosse did in a sufficient manner vindicate Aristorte; and did
plentifully declaim against the proceedings of the Royal Society. Guanvitn
being surprised, he did not then much oppose him ; but afterwards he did, to the
purpose ; especially against this hypothesis of Crosse, that Artstorie had more
advantages for Mistolede than the Royal Society, or all the present age had or could
have, because he did totam peragrare Asiam.”—Athene Oxontenses, vol ii. p. 753.
See the account ves Guanvitt himself gives of this conference, Plus Ultra,

p: 4, 5.

+ Woon’s Athen. Oxon. vol. ii. p. 562, 563.

PHILOSOPHICAL WRITINGS OF LORD BACON. 407

rous, and. all of them replete with misapplied learning, and ve-
hement abuse. The course of his reasoning is not a little cu-
rious. ‘ Ihave so small a regard,” says he, “ for deep and
“ subtle inquiries into natural philosophy, that could physic
“ be unconcerned, could religion remain unshaken, could edu-
“ cation be carried on happily, I should not intermeddle; but if
“ we look de facto upon those experimental philosophers, and
“ judge how little they are fitted for trusts and managements.
“ of business, by their so famed mechanical education, we must
“ rise as high i in our resentments as the eoricams of the pre-
“ sent age and of posterity can animate us.” ‘The grounds
which oe more Pe assigns for entertaining these “ high
«e resentments” against the experimentalists, are, first, their
neglect and contempt of the Aristotelian logic; “ that art,”
says she, “ by which the prudent are discriminated from fools ;
“ which informs us of the validity of consequences, and the
ct probability of arguments, and which forms statesmen, di-
“ vines, physicians, and lawyers.” In the next place, he con-
tends, that the innovating spirit of their ey eee. would lead
to ‘dangerous revolutions. “Tn such times,” says he, “ as I
= thought it our interest to subvert the monarchy of England,
“and the repute of the clergy, I was passionately addicted to
« ‘this new philosophy ; for 1 “did not question but the autho-
« ‘rity of all antiquity in spiritual affairs would vanish, when it
“ appeared how much churchmen were mistaken in the com-
“ mon occurrences and histories of nature. How rational this
“ opinion of mine was, and how it is verified in these days, let
“ the Hierarchy and Universities judge *.”

With

s

* Stupze’s Legends no Histories ; or, a specimen of some animadzersions upon the
History of the Royal Society. Pref. 4to. Lond. 1670.

408 ON THE SCOPE AND INFLUENCE OF THK

With such views of the new philosophy, this infatuated Ari-
stotelian could not but wish to decry the authority of any one
who was more particularly considered as its author. That he
himself looked upon the experimentalists of that day as the
disciples of Bacon, is sufficiently evident from this, that his
common mode of designating them, is to call them in derision
“« a Bacon-faced generation*.” To abuse Lord Bacon, and to de-
preciate his philosophical character, are accordingly his favourite
topics. Nor does he leave us in any doubt as to the cause of
his enmity. It was,as he expressly tells us, “‘ because the repute
“ of Lord Bacon was great in that age + ;’ and because “ the
“ Royal Society pretended to tread in his footsteps }.” He al-
lows that Bacon was a wise and eloquent man; but with re-
spect to his censures of the philosophy and methods of the an-
cients, there, says he, he was insufferably in error. ‘“ Who
“ knows not,” he asks, ‘‘ how Herbary had been improved by
« Turorurastus, Dioscoripes, the Arabians, and other Peri-
“ patetics ? who can deny that Physic, in every part of it was
“ improved, by Gaxen and others, before the Lord Bacon
“ ever sucked ? and what accessionals had not Chemistry recei-
“ ved by the cultivation of the Aristotelians, before his House
“ of Solomon was dreamed of ? Let us, therefore, not be con-
“ cluded by the aphorisms of this Lord. Let his insulse ad-
“¢ herents buy some salt, and make use of more than one grain
«« when they read him; and let us believe better of the an-
“ cients, than that their methods of science were so unfruit-
“ ful ||.” It was the confident belief of this misguided man,

that

pel Dae odo aw naa pee a
* Srusse’s Epistolary Discourse concerning Phlebotomy, passim. 4to. Lond.
1671. ;
+ Lord Bacon’s Relation of the Sweating Sickness examined, p. 2. 4to. Lond.
1671.
+ Legends no Histories, p. 29,
}) Lord Bacon’s Relation of the Sweating Sickness examined, Pref. p. 5.

PHILOSOPHICAL WRITINGS OF LORD BACON. 409

that Bacon’s fame was wholly owing to the false notions of phi-
losophy then entertained, and that it could not fail to fade
with the recurrence of sounder views. “The Lord Bacon,”
says he, “ is like great piles; when the sun is not high, they
** cast an extraordinary shadow over the earth, which lessen-
“ eth as the sun grows vertical *.” How vain the prophecy
involved in this uncouth simile! The fame of Bacon has
brightened as Science has advanced, every new discovery bring-
ing a fresh proof of that transcendent sagacity which enabled
him so unerringly to plan and predict the indefinite enlarge-
ment of her Empire.

ee

The preceding illustrations of the influence of Bacon’s wri-
tings, are confined to the effects which they produced in Eng-
land. It remains to be inquired, Whether they were atc.
tive, in any degree, of any similar effects, in the other coun-
tries of Europe? It is the opinion of some, who are far from
being otherwise sceptical as to their influence, that these writ-
ings were, for a long period, but little known upon the Conti-
nent ; and consequently, that all their effects, of a direct kind,
were limited to England. This opinion has been lately avow-
ed by one of the most enlightened and ardent of Bacon’s ad-
mirers; one whose extensive knowledge in regard to the his-
tory of learning, I shall hardly, I trust, be suspected of any in-
tention to bring into doubt, by dissenting from his statements
on this particular question.

“ That the works of Bacon,” says Mr Stewart, “ were but
“ little read in France till after the publication of D’Atem-

Vou. VIII. P. II. 3F S BERT’S

* Sruser’s Legends no Histories, p. 28.

410 ON THE SCOPE AND INFLUENCE OF THE

* pert’s Preliminary Discourse to the Encyclopedic, is, I be-
lieve, an unquestionable fact ; not that it necessarily follows
“ from this, that, even in France, no previous effects had been
“ produced by the labours of Bortz, of Newron, and of the
“ other English experimentalists, trained in Bacon’s schodl.”
Mr Srewarr farther observes, generally, “ that the merits of
“© Bacon failed, for a century and a half, to command the ge-
“ neral admiration of Europe. Nor was Bacon himself,” he
continues, “ unapprised of the slow growth of his posthumous
“ fame. No writer seems ever to have felt more deeply, that
“ he properly belonged to a later, and more enlightened age ;
“a sentiment which he has pathetically expressed’ in that
“ clause of his testament, where he ‘ bequeaths his name to
“¢ posterity after some generations shall be past *.’”

In making these statements, Mr Srewarr seems to have
overlooked a crowd of testimonies, which prove in the most.
satisfactory manner, that Bacon’s philosophical fame was early
established, not only in France, but in all the other countries of
Europe, where letters were cultivated. I must farther be per-
mitted to express some doubt, whether Mr Stewart has rightly.
interpreted that truly affecting clause of Bacon’s Testament to
which he so eloquently alludes. There are no contemporary publi-
cations which give any countenance to the supposition, that Ba-

‘CON

* Dissertation on the Progress of Metaphysical, Ethical, and Political Philoso-
phy, p. 58, 85. 5 prefixed to the Supplement to the Encyclopaedia Britannica.—
These statements have been already questioned, in part, in the article of the
Edinburgh Review before referred to. ‘The able author of that article contends,
that Bacon’s fame was early and generally established throughout the Continent ;
but he admits, that it was late before any beneficial effects were produced by

his philosophy.

PHILOSOPIIICAL WRITINGS OF LORD BACON. 411

con himself thought his writings had not met with due atten-
tion from the learned world. We have, indeed, his own evi-
dence to the contrary, in regard to the most important, and, as
he himself says, the most “ abstruse” of them,—the Novum Or-
ganum. “ I have received,” says he, “ from many parts be-
“ yond the seas, testimonies touching that work, much beyond
“ what I could have expected at the first in-so abstruse an
“ argument *.” It is probable, therefore, that the bequest
of his Name to future generations, referred rather to his
public than to his philosophical character. In his act of submis-
sion presented to the House of Peers after his disgrace, he im-
plored them to recollect, that there are “ vitia temporis as well as
“ vitia hominis ;” and he perhaps soothed his wounded spirit
with the hope, that posterity would find an excuse for his frail-
ties, in the lax notions and practices of the age; and would
look upon his fall, to use a comparison of his own, “ but as a
“ little picture of night-work, among the fair and excellent
“ tables of his acts and works +.” The exact terms of the
clause, besides, seem to countenance the interpretation, that
his hopes pointed to the greater candour, rather than to the
greater intelligence of after times. “ My name and memory,”
says he, “ I leave to men’s charitable speeches, and to foreign
“ nations, and the next ages {.” But whatever opinion may
be entertained upon this point, it will, I hope, appear eviden

. 3F 2 in

* Epistle to Bishop Anprews, prefixed to An Advertisement touching an Holy
War, written in 1622, and published by Dr Rawxey in 1629, in a collection
entitled, Certain Miscellany Works of Lord Bacon, Ato.

+ Epistle to Bishop Anvrews, prefixed to his Holy War.

¢ Bacon’s Works, vol, iii. p. 677.

412 ON THE SCOPE AND INFLUENCE OF THE

in the sequel, that Bacon’s works were well known, and their
beneficial effects largely acknowledged, in foreign countries,
lone before the period pointed at in the statements of Mr
Srewarr.

In the first place, then, I must observe, generally, that the tes-
timony of such of Bacon’s contemporaries as allude to his writ-
ings, as well as of his earlier Biographers and. Editors, stands de-
cidedly opposed to the supposition, that his fame was of slow
growth upon the Continent. The information which they give
upon this point, rather, indeed, supports a contrary conclusion,
—that the early celebrity of his writings abroad, contributed
to enhance their credit at home. Thus, Gusaws tells us, that it
was the voice of foreign fame which silenced the cry of atheism,
raised against them by some of the School-Divines of his own
country *. Mr Srewarr dates the full acknowledgment of his
philosophical merits in England from the period of the esta-
blishment of the Royal Society +. Now, in the account of
Bacon’s Life, published in 1657 by Dr Rawrzy, who had
been for many years his domestic Chaplain, it is distinctly
stated, “ that his fame was greater, and sounded louder in fo-
“ yeign parts than at home ;” and it is added, “ that divers of
“ his works had been translated more than once into other
“ tongues, both learned and modern, by foreign pens f.” Dr
Rawxry had, some years before, received a strong proof
of the early celebrity of his late Patron’s writings abroad, in
a letter from Isaac Gruter, which contains the following pas-

sage: “ Lewis Exzevir wrote me lately from Amsterdam, that
“ he
i EEEIENEEEee
* Oszorn’s Miscellany of Essays, Paradoxes and Discourses, Preface.
+- Dissertation, p. 158.
+ Life, prefixed to Rawury’s Resuscitatio, first published in 1657.

LALLA PLEA LLL A INE:

PHILOSOPHICAL WRITINGS OF LORD BACON. 418

“ he was designed to begin shortly, an edition in quarto, of all
“ the works of Lord Bacon ; and he desired my advice, and
* any assistance I eould give him; to the end that, as far as
“ possible, these works might come abroad with advantage,
which have been long received with the kindest eulogies, and
“ with the most attested applause of the learned world*.” ‘This
letter was written in 1652, only twenty-six years after Bacon’s
death ; and the important statement which it contains, in re-
gard to the early impression made by his writings in foreign
countries, will be found fully corroborated by a more particu-
lar examination of their literary records.

With respect to France, the only direct authority to which
Mr Srewarr refers, when he states it as “ an unquestionable
“ fact,” that Bacon’s writings were little known in that coun-
try till after the publication of the Encyclopedie, is that of
Montvucra. After quoting a short passage to that effect from
the preface to this writer’s History of Mathematics, he farther
remarks, in a Note, that “ Bayrz has devoted to Bacon only
« twelve lines of his Dictionary +.” But, surely,no weight what-
ever can be attached to this circumstance, when it is recollect-
ed, that Bayie has not devoted even one line of that work,
in the shape of a separate article, either to Gatmro or Des-
cartes. I must, besides, observe, that his notice of Ba-
con, scanty as it is, yet contains enough to show, that
Monructa’s observation is not well founded. The article
mentions, generally, that Bacon’s writings “ had been favour-

“ ably

“cc

* Tennison’s Baconiana, p. 229.—Dr Wars, in the Dedication prefixed to his
translation of the De dugmentis Scientiarum, published in 1674, speaks of Bacon
“as an author well known in the European world.”—Dr Suaw, in the Preface to
his edition of Bacon’s works, published in 1733, says, that “ foreigners appear
to have extolled him in a superlative manner.”

+ Dissertation, p. 58.

4

414 ON THE SCOPE AND INFLUENCE OF THE

“ ably received by the world.” It states, that the Treatise
De Augmentis Scientiarum had been reprinted at Paris in 1624 ;
that is, the year after it was published in London; and re-
ference is made to some high eulogiums, which had been pro-
nounced by French writers upon that important work. It far-
ther mentions, that a number of editions of a French trans-
lation of his moral and political pieces had been called for,
within a short period after its publication; a circumstance
which Baye casually notices in another of his works, the
Reponse aux Questions dun Provincial *. |
That Bacon’s philosophical views were well known in France,
before his death, is a fact, for which we have an authority the
more satisfactory, that it is that of the biographer and disciple
of his great French rival, in the reformation of knowledge.
“ While Descartes,’ says Aprian Batter, in his copious
and instructive life of that philosopher, “ was in Paris in 1626,
“ he heard the news of the death of the Lord Chancellor
“ Bacon, which happened in April of that year. The intel-
“ ligence very sensibly affected those who aspired to the re-
“ establishment of true philosophy ; and who knew, that Bacon
“ had been labouring in that great undertaking for several years
“ before his death. The accomplishment of this heroical de-
“ sign,” continues this devoted Cartesian, “ was reserved for
“ a still more extraordinary genius; but the praises which
“ Bacon received were justly due, even from those who did
“ not approve of his plan for the reformation of philosophy +.”
The

* Chap. 9.—Troisiéme partie—Bacon’s Essays, and his Advancement of Learn-
ing, were translated into the French language a considerable time before his
ae His Natural History, and New Atlantis, were translated into that lan-
guage by Pierre D’Amoorse in 1631. Bacon’s works, says this writer, ‘‘ de-
serve a place in all oes and to be ranked with the noblest literary mo-
numents of antiquity.”

+ La Vie de M. Descartes, par Battier, tom. i. p. 147, 148, 4to.

oi a”

‘

PHILOSOPHICAL WRITINGS OF LORD BACON. 415

The same writer admits, that Bacon’s example may have been
of some use to his French rival ; inasmuch as it was calculated
to encourage him in his design, to abjure the authority of the

ancients, and to re-establish the sciences upon a new founda-

tion *. He farther observes, that Descartes thought Bacon’s

method very well suited to the views of those who were willing

to incur the expence and trouble of instituting experiments 7.
In- making this observation, he refers to some remarkable
passages in Descarres’s letters to Father Mrrsrnnr; one
of which is as follows: “ You formerly wrote me, that you
“knew persons, who were willing to labour for the advance-
“ ment of the sciences, at the cost of all sorts of observations
“ and experiments; now, if any one who is inclined this way,
“could be prevailed upon to undertake a history of the ap-
“pearances of the Heavenly Bodies, to be drawn up accord-
“ ing to the Verulamian method, without the admixture of hypo-
“ thesis ; such a work as this would prove of great utility, and
“ would save mea ae deal of trouble in the prosecution
iad wee <a

AbSNE | Hs Qat eae Thus,

fogs J

* Ua Vie de M. Descartes, tom, i. p. 148,—Descarrtes was about thirty years of
age at Bacon’s death, and did not publish any of his principal ores till several

ee after that period.

Pd 149. ot “4 :

t Lettres de M. Descartes, tom. iv. p. 210. Paris edit. 1724,—It appears from
the following passage in one of Sir Kenetm Dicpy’s letters to Fermar, the rival
of Descartes in mathematical science, that this eminent geometer was a great
admirer of the works of Bacon: “ Je ne scaurois m’empécher de vous envoyer
quelques vers que le plus grand genie de notre Isle pour les Muses écrivit au Chan-
celier Bacon, qui étoit son grand ami, et que vous témoignez étre fort le votre
en le citant souvent.” 13. Fev. 1658,—Letires de M. Fermar, p. 198. annexed
to his Opera Mathematica.

416 ON THE SCOPE AND INFLUENCE OF THE

Thus, it is clear, that more than a hundred years before the
appearance of the Encyclopedic, Bacon’s writings had attract-
ed so much notice in France, as to force them upon the atten-
tion of those who were but little disposed to relish their phi-
losophy. It farther appears, that the first doubts that were
entertained as to the sufficiency of the method of Derscarrzs,
originated among those of his countrymen who had imbibed
the spirit of Bacon’s Logic. The doctrines of the No-
vum Organum are professedly taken as the basis of the argu-
ment, in a letter addressed to Descartes in 1648, by a corre-
spondent who wishes to convince him, that in physical science,
no principles ought to be admitted, but such as have been pre-
viously derived from facts*. In a piece, by a different author,
written some years later, entitled Remarques sur la Methode de
Descartes, Bacon’s method is characterised as follows: “ One
“ sees so much judgment in the rules laid down in the Novum
“ Organum, for guiding the understanding in the search of
“ truth, that one might almost believe its author had been in-
“ spired. This work, indeed, has some defects, particularly in
“ its language, which is often scholastic and fanciful; but far
“ from wishing to dwell upon them, we ought to proclaim,
“ that it is only since the time of Bacon, that the human mind
“ has followed a proper plan in matters of philosophy.” It
is worthy of notice, that the author of this eulogium speaks of
the Royal Society of London, then recently established, in
terms of great approbation ; and as being likely to realise all
Bacon’s views for the advancement of the Sciences.

GassENDI

* Lettre premiere a M. Descartes, prefixed to his T'reatise on the Passions, Pa-
ris edit. 1726. )

+ Remarques sur la Methode de Descartes, p. 128, 129; annexed to his Dis-
cours de la Methode, Paris, 1724.

PHILOSOPHICAL WRITINGS OF LORD BACON. 417

» Gassrnpr was one of the earliest disciples of Bacon in
France ; and he was also one of the earliest and most strenu-
‘ous opponents ef Descarres’s Philosophy. He has characte-
rized the principles of philosophizing, which these two re-
formers respectively professed, in a very clear and able. man-
ner, in the tenth and eleventh chapters of his treatise De Logice
-origine, et varietate*. The reformation attempted by Bacon, is
‘there pronounced a truly great and heroical undertaking. | In
another work, his excellent account of the life of his celebrat-
ed friend Psrrresc, ‘there is a: passage, in which Bacon. is
‘mentioned in a way particularly deserving of notice in the
present discussion. ‘“ No man,” says Gassenp1, speaking of
his friend, “ made more observations, or caused more to be
“made; to the end, that at last some notions. of natural
- things, more sound and pure than those commonly received,
“ might be collected ; for which reason, he admired the ge-
-“ nius, and approved the design of that: great Chancellor of
_eiRglatid, ‘Sir Francis Bacon f.” Now, Pemesc died in
1637, only eleven’ years after Bacon. But this is not all. He
_ was’ the first man in France, according to Bartiy, who deserved
the name of. an’ astronomer {; and he, as well as. GassENnprI,
who was’also distinguished as an astronomer,—was a correspon-
‘Menttirieadied admirer of GatiLEo; yet we see, that Bacon
"was considered by both, as the great leader of reform in Natu-
‘ral Philosophy. HR

There ‘are many other niecaine of a similar real
in the writings of those who were conversant with the
po oo ame ea tags One of these, that furnished by

TE Ee pi 0 BUGact). bast 99 cup Slot SORBIERRE,

4

* Gassenpr, Opera, tom. i. '

+ Gassenni’s Life of Peiresc, Book vi. p. 207. of the Biiglish te iitbecinge:
+ Histoire de Ll Astronomie Moderne, liv, iii. § 20.

418 ON THE SCOPE AND INFLUENCE OF THE

Sorsierre, in his famous Voyage en Angleterre, published in
1664, is probably entitled to more consideration than his
own name could, of itself, attach to it; tor he had acted for
some time as the Secretary of one of those associations of Pari-
sian philosophers in which the Academy of Scicnees had its be-
ginning *. “ Ce grand homme,” says he, speaking of Bacon,
“ est sans doute celuy qui a le plus puissamment solicité les in-
“ terests de la physique, et excité le monde a faire des ex-
* periences +.” A similar observation is made, and in words
equally strong, by the Abbé Gators, in one of the numbers
of the Journal des Savans, published in 1666; a year signalized
by the establishment of the Academy of Sciences {. Bacon is
also represented as the father of the inductive or experimental
method, by Joun Baptiste pu Hamet, the person who first
held the office of Secretary to that Academy. His treatise De
Mente Humana, published in 1672, contains seyeral chapters
of commentary upon Bacon’s Philosophy ||.. We are told by
FontTENELLE, that Du Hamen was censured by his contempo-
raries, as not being sufficiently regardful of the merits of Des-
cartes §. With such views as he seems to have imbibed
from the writings of Bacon, he must, indeed, have been but
little disposed to look up to Descartes as the oracle of philo-
sophy. big
It

* Bincn’s History of the Royal Society, vol. i. p. 27.
+ SorsrerRe, Relation Cun Voyage en Angleterre.

+ « On peut dire que ce grand Chancelier est un de ceux qui ont Jes plus con.
tribué 3 3 Pavancement des sciences.”—Journal des Savans, du 2. Mars, 1666.

\| Lib. i. cap. 3. § 7.5 Lib. iii. cap. 6, 7, 8, 9.
§ Fonrenzuie, Eloge de Du Hamel.

—

——————

PHILOSOPHICAL WRITINGS OF LORD BACON. 419

It would be quite. unnecessary to proceed any farther, in ac-
cumulating French authorities. The preceding deduction is
sufficient to establish, not only that there is no foundation what-
ever for the statement, that Bacon’s writings were little known
in France previous to the publication of the Encyclopedie ; but
that they had, at»a much earlier period, made an impression in
that country, greatly favourable to the progress of truth*. I .
shall, therefore, go on to inquire, though in a cursory man-
ner, whether there are any similar proofs of equally early, at-
tention having been paid to them, by the other lettered na-
tions of the: Glonibindinie:

Turning to Italy, we shall find, that caene also, Bacon’s philo-
sophical works had attracted considerable notice, even before
his death. Itis evident from his correspondence with Father
Fuxeentio, that the Venetian philosophers were extremely in-
quisitive about his publications +. His correspondence with
Father Baranzan proves, that the Novum Organum was known,
and had found anxious readers, in the north of Italy, at a surpri-
wif 3G 2 singly

- #* D’Avemnerr, in his Preliminary Discourse, assumes, that Bacon's writings
remained long unheeded, and then exerts his ingenuity to show how this re-
sult was to be expected. ‘ La scholastique qui dominoit de son temps, ne
pouvoit étre renversée que. par des opinions hardies et nouvelles ; et il n’y a pas
apparence qu'un philosophe, qui se contente de dire,—Vorla le peu que vous avez
appris, voici ce qwil vous reste a chercher, soit destiné a faire beaucoup de bruit par-
mi ses contemporains.” But were not Bacon’s opinions sufficiently bold, new,
and animating, to attract the notice of an age already disposed to innova-
tion? Did he not proclaim in the most energetic terms, that the whole of the
antient systems and methods of philosophy must be abandoned as corrupt and
incapable ; ; that the true path to science had been delineated only by him; and
that countless discoveries waited to reward those who should follow that path
with free minds and regulated perseverance ? \
—— “ He tryd each art, reprov’d each dull delay,
Allur’d to brighter worlds, and led the way.”

+ Tenntson’s Baconiana, p. 196, 197.

420 ON THE SCOPE AND INFLUENCE OF THE

singly early period. Baranzan was.a Piedmontese monk of the
order of Barnabites, and officiated as a Professor of Philosophy
and Mathematics, in the Colleges of his order. He had early
distinguished himself as a writer on philosophical subjects,
and as a discarder of the authority of Arisrorne. After per-
using the Novum Organwn, he appears to have begun a corre-
spondence with Bacon, one of whose letters to him is fortu-
nately preserved. in the account of Baranzay’s life in Nice-
ron’s Memoirs *. This letter is dated in 1622, only two years
after the publication of the Novum Organum; and was evi-
dently written, in answer to some queries/of Baranzan, touch-
ing its fundamental doctrines. The whole letter is on this ac-
count extremely interesting ; but the following passage may be
cited, as more particularly calculated to show, how much phi-
losophy then stood in need of such a guide as Bacon. “ De
‘ multitudine instantiarum, que homines deterrere possit, hac
“ respondeo: quid opus est dissimulatione ?. Aut copia in-
“ stantiarum comparanda, aut negotium deserendum. Alize
omnes vie, utcunque blandiantur, impervie.” It is worthy
of notice, that Bacon concludes this letter with an earnest
request, that Baranzan would employ himself in framing a
description of the heavenly bodies, exactly of the kind which
Descarvres afterwards wished some competent person to un-
dertake ; as mentioned in his letter, before quoted, to Father
Mersenne. But this ingenious Italian was not permitted to
profit by the exhortations of his illustrious correspondent, for
he died soon after the date of this letter, at the early age of
thirty-three. .

ral

“ce

There

* «© Ble est trop interessante,” says Nrcrron, who possessed the original let-
ter, “ et fait trop bien connoitre la maniere de philosopher, qu‘ils vouloient tous
deux introduire, pour ne la point communiquer au publique.” —Memotres pou
servir a Uhistotre des Hommes Illustres, tom. iii. p. 43.

PHILOSOPHICAL WRITINGS OF LORD BACON. 421

There is'a letter’from Sir Tosy Marrurw to Bacon, which
contains .a curious piece’ of information,’ not -hitherto parti-
cularly noticed, I believe, by any of the learned. It’ was
written from Brussels in-1619, when Sir Toy was on his re-
turn’ to Florence,’ where, during ’a former residence, he' had
published an Italian translation of Bacon’s Essays. \ “ There
“was with me'to-day,”’ says he, “ one Mr Riewarp Wut,
“ who hath ‘spent ‘some time at Florence, and is now go-
“ing to England. ‘He tells me, that Garitzo had answer-

“ ed your discourseeoncerning the flux and reflux of the sea;
“ and*was ‘sending it unto me; but that he hindered Ga-
‘“ y180, because his’answer was founded upon a false sup-
“ position’; “namely, that there was in the ocean a full sea but
“ once’ in the twenty-four hours. But now,” adds Sir Tory,
«JT will call upon Gaxineo ‘again *.”’ As the discourse on ‘the
Tides, here alluded to, was not ‘published till several years af-
ter Bacon’s death +, it must have been sent to Gatiiz0 in ma-
nuscript. What farther’ eommunication took place upon. the
subject, does not appear. | There is’ no allusion to any of Ba-
con’s writings, so far as I know, in the works of GaLiLEo;
though the circumstance just mentioned, and the unquestionable
notoriety of these writings in Italy, during’ his time, render it
difficult to believe, that he had not perused them. The fol+
lowing passage, contained in a letter written from thence to the
Earl of Peseieed near, but before the time of Bacon’s death,
athivasord wilqoaakiah we t “furnishes

* Bacon’s Works, vol. iii. p. 562.

+ It was first published, I believe, by Isaac Gruter in 1653, in the collec.
tion entitled Fran. Baconr de Verulamio Scripta in Naturali et Universali Phi-
losophia, 12mo, Amst, The pieces contained in this collection, were given: to
Groter by Sir Wiut14m Boswext, the English Resident in Holland, to whom
Bacon had committed them by his will.

422 ON THE SCOPE AND INFLUENCE OF THE

furnishes an additional-proof of that notoriety. “ Lord Bacow,”
says the writer, “is here, more and more known, and his works
* more and more delighted in *.” |
There was an Italian: philosopher of that period, whose
ardent genius, the cruel torture of the rack, and twenty-
seven years imprisonment, had not been able to repress ; whe
fortunately found a friend, to publish in Germany, the works
which he penned in the prisons of Naples ; and who has had the
honour to be placed in the same rank with Bacon, by no less a
judge of philosophical merit than Lemyirz. This was Camra-
weLLa. “ If,’ says Lemnirz, “ we compare Descarres and
“ Hoxnses, with Bacon and Campanetna, the former writers
“ seem to grovel upon the earth,—the latter to soar to the
“ heavens, by the vastness of their conceptions, their plans,
“ and their enterprises.”—‘ After looking,’ says Mr Srew-
art, (from whose rich stores of varied erudition I have bor-
rowed this quotation,) “into several of CampanrLia’s works,
“ with some attention, I must confess, I am at a loss to con-
“ ceive, upon what grounds this eulogy proceeds }.” But, how-
ever just Mr Srewart’s surprise, Lzmwnrrz was not the first
who conjoined the names of Bacon,and CamraneLia. Tostas
Apans, the person who performed the task of editing those works
which CampaneLta wrote in prison, tells us, in his introduc-
tion to the Realis Philosophia of the latter, published at Frank-
fort in 1623, that CampaneLa, like the great VeruLam, took
experience for his guide, and drew his philosophy from the
book of nature {. The comparison here, is as unsound, as the
eulogy

* See Bacon’s Life, prefixed to Rawney’s Rescuscitatio.

+ Dissertation, p. 39.
+ Realis Philosophie Epilogistice partes quatuor ; hoc est, de rerwn natura, ho-
minum moribus, politica, et economica ; cum adnot. Tuos. Apamt.

ee oo

hee St ng

PHILOSOPHICAL WRITINGS OF LORD BACON. 423

eulogy of Lasyirz issexcessive ; but it is remarkable, as show-
ing, that the’ scope and objects of Bacon’s Philosophy were
known and approved, at this early period, in Germany. We have
another illustration of the early diffusion of his views in that
country, in»CommeEntus’s Synopsis Physice ad lumen divinum
reformate, published in) 1643; in which work, the author
speaks of the Novum Organum in the highest terms of praise ;
and warns his readers, that it was not his wish to interfere with
the'great plan of discovery which it proposes; but to make a
trial, whether the lights of Scripture might not assist in the
interpretation of nature *.

Among the German writers of the Jater half of the seven-
teenth century, who either professedly or incidentally treat of
the history of philosophy, there are various references to be
found to the writings of Bacon, coupled with the strongest ac-
knowledyments of their beneficial influence.. Some of them
ascribe merits to his works which have been pointedly disclaim-
ed by the more discriminating of his English admirers, Thus
Moruor, besides the other praises which he lavishes, upon him,
etal oy Mr eteyay ‘s affirms

ee Ego quia ia lumine Dei lumen videre visus sum, temperare mihi non
potui,.quin, adyocato in auxilium Deo, novas naturalium hypotheses in novam
methodum redigere,, discipulisque Schole hujus dictare, tentarim. Non quod
magni Vevsamn ‘consilio (qui ab axiomatibus, antequam de omnibus et singulis:
plenee’ per universam Naturam inductiones exstent, abstinendum esse censet) ad-
oh ire vellem; sed ad: capiendum interea experimentum, numnam ratione ;

hac | lus. luminis, ad\ Nature arcana’ facilius observandum, inferri, possit | menti-
bus. ”—-COMMENII, Physice ad lumen divinum reformate Synopsisy (Pref.

In this. work, also, Campaneuca is mentioned in conjunction with Bacon, for
reasons which render the passage deserving of notice here... * Videat autem qui
volet CamPanELLAM et Verunamium (hos: enim Hercunes, qui debellandis mon-
stris expurgandisque Augie stabulis, feliciter admoverunt manus commonstrasse ;
et illis, quos Aristotelicee vané turgid Philosophiz dementatos tenet authoritas,.
opposuisse, sufficiat) ; et. quam sepé A vero aberrent. Aristotelice assertiones, pal-
pare poterit.”—Preef.

424 ‘ON THE SCOPE AND INFLUENCE OF THE

affirms, that his works contain the germs of many important
discoveries in physics,the glory attached to which, though wholly
reaped by others, was partly due to him*. His services to
physics, are much more correctly indicated, by another well
known German writer of that period, namely, Baron Purren-
porr. “ It was the late Chancellor Bacon,” says he, “ who raised
“ the standard, and urged on the march of discovery ; so that if
“ any considerable improvements have been made in philoso-
“ phy, in this age, there has been not a little owing to that
“ oreat man f.” L oily
Descending somewhat lower in point of time, though keep-
ing still within the period of the supposed abeyance of Bacon’s
fame on the Continent, we find Bupprus, a writer of un-
questionable knowledge, representing him, as having comple-
ted the overthrow of the authority of ArisrorLz, and as having
not only described the true method, but powerfully accelera-
ted the progress of scientific discovery }. I shall only add one
authority

* Mornort, Polyhistor. tom. ii. lib. 2. cap. 1.—Moruor gives the follow-
ing notice of a work published in Hungary in 1663, in which an attempt
was made to explain the principles of Bacon’s philosophy. Ex mente Vz-
RULAMU queedam in sua universali methodo institiere voluit Jouannes Bayervs,
libro cui titulus: Filum Labyrinthi, sive Lux mentium universalis, cognoscendis, ex-
pendendis et communicandis universis rebus accensa. Verum obscurat potius Vz-
RULAMIE sensus omnemque philosophiam, quam ut lumen aliquod accendat.”—
Polyhist. tom. i. lib. 2. cap. 7. The title of Bavenr’s work is, partly, that of one
Bacon’s philosophical fragments, (Filum Labyrinthi) ; and however imperfect
his work may be as an exposition of Bacon’s views, it shows that his philosophi-
cal writings had early engaged the attention of the learned, even in the more ob-
scure parts of the Continent. '

+ Specimen. Controvers. Cap. i. sect. 5. apud Pore. Buount—Censura Celeb.
Author, p. 635.

‘+ Buppe1, Compendium Historia Philosophie p. 409, 410, Edit. 1731.

PHILOSOPHICAL WRITINGS OF LORD BACON. 425

authority more, that of a celebrated. Dutch writer of the same
day, himself an eminent improver of science in several of its
branches ; and who was placed in a situation, which, in a parti-
cular manner, enabled him to collect the general sentiment of
Europe, upon any point connected with the history of philoso-
phy. Ihere allude to Borrwaave ; who, in his Discourse de com-
parando certo in Physicis, delivered before the University of Ley-
den, when he Jaid down the office of Rector in 1715, pronounced
an eulogium upon the merits and services of Bacon, which I
am happy to extract as a conclusion, ornament, and sanction,
to the foregoing observations.— Atque hujus quidem Physi-
“ ces fortunas laudare licet ex quo magnum VERULAMIUM sum-
“ mo suo bono accepit! Virum certé ad omnia, que scientid
“ humana comprehendi possunt, indaganda facilé principem,
“© et de quo dubites utrum consilio, an exemplo, major fuerit
“ in instauranda deformaté Physica. Absque invidid dixero,
“ quidquid incrementi cepit naturalis historia ab ineunte de-
** cimo sexto seculo in hane usque horam, omne id acceptum
“‘ debemus monitis et preceptis illius viri; cujus indelibilem
“ memoriam grata colet orbis perpetuitas. Gratari quoque
“ oportet zvo nostro, quo exire servitio sectarum licuit, sicque
“ ardere puram, castamque, veritatem, ut, posthabitd figmen-
“ torum atque commentorum auctoritate, Naturam solam suas
“ dotes revelantem audiamus,” .

Vor. VIII. P. IL 3H XX.

’
;
-

SE ILE

a aoa ea

XX. Sketch of the Geology of the Environs of Nice. By
Tuomas Auuan, Ese. F. R. 8. Enin.

(Read 16th Feb. 1818.)

Nie is situated on the shore of the Mediterranean, in lat...

43° 41°16” N. and long. east of Greenwich 7° 16’ 37’. The
county of which Nice is the:capital, was comprehended in the
Roman province of the: Maritime Alps: it was included, while
under the influence-of France, in a department to which the
same name was given; and now, it is restored to the sovereign-
ty of Piémont, it may be considered as bounded on the west
by the Var, which separates it from France, on the north and
east by the mountains of Dauphiné and Piémont, and.on the
south, it is washed by the Mediterranean.

Its situation is very peculiar; although scarcely ten leagues
distant from one of the highest ranges of the Alps, it has a cli-
mate to boast of, equal to that. of Naples or Sicily, which may
be attributed to local and very peculiar circumstances. The
town and the little plain of Nice, are'situated immediately under
the shelter of Mount Boron, which intercepts the direct blast
of the Levant winds. This hill is the commencement of a se-

38H 2 ries

428 ON THE GEOLOGY OF THE

ries which surround it on all sides, except the south: these
rise with considerable abruptness, to a height of from 500 to
1000 feet, gradually increasing till they approach Mount Cao
or Calvo, by some called Mount Chauve, from the bald, herb-
less aspect of its summit. This mountain towers majestically
over the rest, and forms an imposing feature in the group. I
was informed by M. Russo, that its altitude had been ascertain-
ed to be 440 toises, about 2650 feet.

Beyond this range there is a second, which eee it from
the High Alps. ° Tes most prominent points, as seen from
Nice, are the Col de Brois, the Trois Mamelons, the Col
d’Autillons, the Vierge d’Utelle, &c.; and then as a third de-
fence, the Alps encircle the whole; protecting this favoured
spot, on the west, by that branch which stretches through
Provence, and terminates by the mountains of Les Estrelles
in the sea, at a point denominated by Saussure Cap Roux; on
the north, by that elevated range, whose snowy summits pre-
sent a striking contrast with the ceaseless verdure of the plain
below ; and on the east, by that group which forms the rugged
country of the Corniche, and which, by the abrupt manner it
terminates in the sea, has shut up the most natural and direct
access into Italy; and unfortunately, the policy of the Sardi-
nian Government has prevented the energy and industry of
mankind from being exerted in removing the difficulties which
Nature has here interposed *.

It is, however, to a very small proportion of this territory
that my observations extend, having been confined to within a

forenoon’s

* Bonaparte saw the advantage which must accrue to the country by a tho-
roughfare being opened in this direction, and commanded a road to be construct-
ed, fit for every purpose between Nice and Genoa. Already one-third of this
imperial undertaking is completed, one-third of the road is marked out, and the re-

mainder

:
|

ENVIRONS OF NICE. 429

forenoon’s ride of the town of Nice, one mile and a half from
which, I resided.

I may notice, however, that if the circle were narrow, the
country possessed peculiar advantages, in the wonderful un-
evenness of a surface, which, beyond the little plain, seldom
presented one hundred yards of flat ground; and while it afforded
the most ample opportunities for investigating its geological
structure, the pleasing and diversified aspects, which this broken
ground, clothed with the orange and the olive, every where
presented, stimulated as well as recompensed the labours of
research.

On my arrival at Nice, I by no means anticipated much in-
terest in my examinations, from the constant occurrence of
limestone; but with the assistance of M. Risso, a gentle-
man who has recommended himself to the scientific world, by
several very interesting works on Natural History *, who kind-
ly pointed out such objects as had previously attracted the at-
tention of observers, I was quickly undeceived, and found, not-
withstanding the apparent uniformity of the country, that it
contained much matter for the contemplation of the geologist,
and afforded materials which seem to bring down the ope-
rations of Nature to a less remote period than is done by

the
a ts ee ee

mainder continues only practicable to mules and pedestrians. So much were the
Genoese (now also Sardinian subjects) sensible of the advantage which this road
would be to them, that they offered, after the restoration, to accomplish the un-
dertaking, on being allowed to reimburse themselves by means of a toll ; but the
proposal was rejected. It is curious to reflect, that this road, now so unfit for
the purposes of communication, was the great Roman way into Spain, and the
same by which the armies of Cuartes V. invaded France during his contests with
Francis I.

* His last publication is entitled, Histoire Naturelle de Crustacés des Environs
de Nice. Paris, 1816.

430 ON THE GEOLOGY OF THE

the conclusions drawn from the examination of any other dis-
trict that I am acquainted with. The observations which have
within these few years been given to the world on the Paris
basin, and on the similar country of Hampshire and the Isle
of Wight, are extremely interesting, and in fact opened a new
source of geological research ; but the phenomena, as present-
ed in both these situations, are surrounded with so many diffi-
culties, that as yet they can hardly be considered as grounds
for the foundation of any general conclusion: In the vicinity
of Nice, many similar phenomena occur; but they are accom-
panied with indications which render the nature of their origin
more evident, and consequently very greatly enhance their value.
The Limestone of Nice consists of two kinds,which, for the
sake of perspicuity, I shall call the jirst and second ; and I fear
T shall be under the necessity of being contented, though not
satisfied, with these appellations. For, although the distinction
be so marked in the neighbourhood of Nice, as not to admit of
any hesitation, yet I found, on leaving that district, when the
second began to:predominate, it assumed so much the texture
and appearance of the first, that I could not have known the
difference. I thought I might have been able to avail myself
of the terms calcaire compacte, calcaire caverneuse, or Jura-
Limestone. Neither of the two first are correct, as limestones
of very different formations are found equally compact, and
equally remarkable from the caverns that occur in them; and
with respect to the name Jura, as a distinctive geological term,
I think it extremely unfit ; because, in: passing the range which
bears that name, from Gex to Poligny, I noticed great variety in
the composition of the limestone, of which its mountains are
formed. On the south side, it very much resembled the first
limestone of Nice, but contained more organic remains. Be-
fore arriving at Poligny, it bore more the aspect of the lime-
stone

4

ENVIRONS OF NICE. 431

stone of Derbyshire, and was accompanied with vast quantities
of chert or flint, disposed in continuous lines, nearly horizon-
tal, and parallel with the strata. In using the terms jirst and
second, 1 involve no theory, although, perhaps, I would not
have been far from the truth, had I adopted the more scienti-
fic language of Transition and Fletz.

The first limestone, then, occurs in beds, distinctly stratified,
inclined more or less to the east or north-east, being very un-
favourable to vegetation, where the situations are exposed: the
hills are often so destitute of covering, that the lines of the
strata may be traced from the base on one side to that on the
other, as distinctly as the ridges in a fresh-ploughed field.

This limestone is sometimes of a very compact texture, with
an even large conchoidal fracture, generally smooth, but occa-
sionally approaching to splintery: it breaks in sharp-edged
fragments, faintly translucent, and somewhat scopiform: its
colour is a pale brown or drab, and it presents no trace of
crystallisation. It is in all likelihood from this variety the name
of Compact Limestone was derived. In some of the strata,
however, a gradual transition from the compact to the crystal-
line may be traced; and as the crystallisation becomes more

perfect, the colouring matter disappears, so that we have it

sometimes as white as the statuary marble of Carrara. Its tex-
ture also changes as the crystallisation proceeds : it first be-
comes splintery, and then passes on to a rough uneven frac-
ture, consequently differing very much from the saccharine
structure of the statuary marbles. In the little hollows which
occasionally occur in this variety, we find the calcareous rhomb -
in groups of crystals very regularly formed; and where the
crystallisation appears to have been pushed a little farther, the
mass has become extremely friable, with a gritty feel, and
seems to be entirely formed of rhombs. These strata have
sometimes,

432 ON THE GEOLOGY OF THE

sometimes, though very rarely, a marly ferruginous matter i=

terposed between them, but I have not observed it of more
than two or three inches in thickness ; it is very much given:
to decompose.

Of this limestone there is another variety, of a dark-brown
colour, extremely compact, with the vitreous texture of our in-
durated sandstone, or the Felspath ceroide of the French : it is
less common than the others. °

In the first limestone, | have found flint, not generally, but
very frequently ; and where the rocks were well exposed, I
have seen the nodules tracing their line along the centre of
the beds, exactly in the same manner as in the white limestone
of Antrim, or among the chalk cliffs of the Isle of Wight.
Organic remains do not frequently occur in it: they are found,
however, and in one spot in remarkable abundance. The dif-
ferent organised bodies I noticed, are a cornu ammonis, an echi-
nus, a pecten, and coralloids ; all but the last in single detach-
ed specimens ; but the coralloids abound at a spot about 150
yards east of the Lighthouse on St Hospice. It is curious to
observe the effects of the weather on the surfaces of some of
the blocks of this limestone. The substance of the petrified
organized bodies being harder, they have resisted the action,
while the matter in which they were included has been washed
away ; so that in some places the corals may be detached, quite
relieved from the paste which once enveloped them, and form-
ing a net-work on the surface, not unlike what we often see in
the branches of ivy on the surface of a wall, .

Near this, there are two or three other strata which are
crowded with the remains of corals, fragments of the shell of
the echinus, and various. other debris. ‘These particular beds.
resemble some of the limestones of England, having the or-
ganised bodies crystallised, and inclosed) in a paste of compact

limestone.
This

—

ENVIRONS OF NICE. 433

This stone is peculiarly hard, brittle, and very sonorous :
the colour is a light brown, tinged with red. Here, also, the
action of the weather leaves the petrified portions projecting,
and produces a very rough and arid surface. I understand
this coral limestone has been described by M. Sr Fonp as a
particular formation. No doubt the beds which contain these
organic bodies, differ from such as contain none. They, how-
ever, form portions of the same series of stratification, and, so
far as I understand the term, are parts of the same Forma-
tion.

Having described the characters and composition of the first
limestone, I shall proceed to notice the caves which so fre-
quently occur in it. These are found, not only on the shore
of the sea, but high on the summits and sides of the hills,
where no running water, according to the present order of
things, could ever have existed. I have also seen portions of
cavities displayed in a much more instructive situation, in the
line of the new Genoa read, pompously denominated Le Che-
min de Rome. Were they have been cut through in the pro-
gress of that useful, but now abandoned undertaking, and the
sections laid completely open to view. To what these cavities
are to be attributed, it is very difficult to determine ; but from
the appearance of dislocation which is observed accompanying
those last mentioned, it is probable they are indebted for their
formation to some great concussion ; but whether proceeding
from above or below, we may perhaps be better able to hazard
a suggestion in the sequel.

Connected, as I conceive, with these caverns, is the broken
and fragmented state in which we very frequently find the first
limestone, forming the Brésche en place of Saussurr, one of
the most interesting circumstances which occur in the history

of this substance. Upon the tops of the mountains, in loose

Vor. VIII. P. IL. 3I fragments,

434 ON THE GEOLOGY OF THE

fragments, and in caverns, in massive columns, we find a
great deal of that stalactitic limestone known by the name of
Antique alabaster, which is likewise found filling the rents, and
forming the cement of the Brésche en place. The mode in
which this substance has been infiltrated, is finely exemplified in
the sections laid open in forming the new road above alluded to,
where cavities occur, in some respects very much resembling
those of calcedony, as seen in the trap rocks of Feroe, though on
avery different scale. The calcareous matter has been deposited.
gently and slowly on the sides of the hollow, here and there
has fallen in stalactites from the summit, either disengaged in
columns, or along the sides, and then forming horizontal plat-
forms at the bottom, like the onyx in thousands of the pebbles
which occur in the amygdaloid of Scotland. Connected with
all these, however, is the vein by which the infiltration was in-
troduced ; and in this lies the distinction between those calca-
reous and the calcedonic geodes.

Besides this species of cement, there are others, one of which
forms a very compact limestone, and often presents an even con-
choidal fracture, of a pale reddish-brown colour, and frequent-
ly dendritic ; this passes into a coarser variety, with somewhat
of a splintery fracture, and of a dark-red colour. There
are some very remarkable examples of the infiltration of this
material, where the great beds of limestone are not only as it
were soldered together, but where, having been broken down
into the smallest fragments, they are again consolidated, and
form the most compact masses. . Another cement is of a pale
brick-red colour, more earthy in its texture ; and when it forms
the base of the white variety of limestone, it has a very beau-
tiful and singular effect. The fragments are sometimes in very
large masses, and sometimes in very minute particles. Where
exposed to the action of the weather, the cement is frequently

washed

t

ENVIRONS OF NICE. 435

washed from the surface, and leaves the fragments like a heap
of gravel. This broken and fragmented state of the limestone,
so far as I have been able to observe, is more prevalent on the
outskirts and surfaces of the hills, than in places which have
been worn down by the action of rivers; and in the neighbour-
hood of Nice it is entirely peculiar to the first limestone.

All the cements are more or less argillaceous, and if I may
except an occasional appearance of pyrites, and now and then
the occurrence of shells, I did not observe any other extra-
neous admixture. The appearance of shells, however, in the
paste which agglutinates the fragments of the first limestone, is
a very curious igaae They must have existed, possibly alive,
but certainly, or at least in all probability, in a recent state,
when this agglutination took place, and have been drawn in
along with the cement. It is a fact highly deserving attention,
pacicalacly when the shells are found at a poe tees eleva-
tion. I remember being much surprised at finding some mi-
nute shells included in “the brescia near my hetero: ; but up-
on these, as the paste was so unusually superabundant, and
as the spot was not exposed in a very satisfactory manner, I did
not conceive I had any sufficient ground to speculate.

I have lately had an opportunity of visiting my friend Mr
Rawuinson Barcray in London. It was in company with this
gentleman I made most of my excursions in the vicinity of
Nice. From among the specimens he had collected after my
departure, he gave me one he had detached from near the sum-
mit of Mount Cao. This specimen is not only remarkable, from
the situation it was found in, but from the circumstance of shells
it contains being derived from very different origins. Accord-
ing to Captain Brown, one has every appearance of the Turbo
Fontinalis ; the second, is only the portion of a reversed shell,
which appears to be part of the Bulla Hypnorum, retaining its
colour and lustre, in a most extraordinary degree. Both these

312 are

436 ON THE GEOLOGY OF TIE

are fresh-water shells; the third, which is of a large size when
compared with the others, is of the exact form of B. Ampulla
of Linnaeus, or Amygdalus of Dituwyn, a marine shell.
That these may have fallen accidentally into fissures, and
have been there conglomerated in the process of time, is
quite possible ; but their occurrence at such an elevation be-
speaks an order of things totally different from that which pre-
vailed at a subsequent period. I shall only further observe,
with respect to the brescia itself, that it is wonderful to see how
completely and perfectly the upfilling has been accomplished.
Instead of the pores being choaked, through which the fluid
must have passed from the surface to.the interior of the rock,
the liquid seems to have been absorbed as if by a sponge, and

the mass presents very often a greater degree of solidity in the

interior than towards the surface.—I shall now proceed to the
Second Limestone.

This variety rests upon the first ; and in this neighbour-
hood is composed of strata very various in their dimen-
sions, measuring from a few inches to two and three feet
in thickness. It may even exceed this, but not frequent-
ly. In this diversity in the dimensions of its strata, it pre-
sents a strong contrast with the First Limestone, whose
beds are found to be remarkably uniform, when we have
favourable opportunities of seeing them displayed. It is ac-
companied occasionally with a poor species of clay-ironstone,
and a kind of blue marly clay, a substance which is very much
given to decompose. Although it rests upon the first lime-
stone, it does not maintain a conformable position: it seems
as if it had been deposited immediately before the hills had
assumed their present forms, and as if by means of their ab-
rupt elevation, to have been thrown aside previous to its per-
fect consolidation, into the valleys in the most complete con-

fusion,

jd

ee a

_ ENVIRONS OF NICE. 437

fusion, sometimes leaning laterally against the first limestone,
sometimes presenting its edges towards it, and very often sin-
gularly contorted.

With regard to its composition, it varies considerably. In
colour it passes from a bluish to a brownish grey ; it is some-
times very tough under the hammer; very hard and close-
grained when it breaks in scopiformly angular fragments ;
faintly translucent on the edges, with somewhat of a splintery.
fracture. Again, it occurs of a dull earthy texture, breaking
into rough irregular masses, and affording a strong argil-
laceous smell. In the compact variety, flint very often occurs,
dispersed irregularly through the mass, not preserving a line,
as it does in the first limestone, nor formed in the same dis-
tinct nodules, but in masses, which appear to be chemically
combined with the limestone. It occasionally contains a pro-
fusion of organic remains. This is particularly the case on the
peninsula of St Hospice, where in one place the rock appears
to be formed of a very minute variety of nautilus, mixed
with small numelites ; different ostrea, the pecten, and gry-
phite, are also found in it, with fragments of the shell of
the echinus. It sometimes happens that the blue marly clay
which accompanies the second limestone, presents itself. in
very thick but always conformable beds; and as nothing grows
upon it in high and exposed situations, it gives a very de-
solate appearance to the country, which, in some places, much
resembles the mining districts of Cornwall, from. the heaps
of naked rubbish thrown down by decomposition. This clay
does not contain many shells. In a few instances, I observed
them sparingly distributed, and not in the perfect state I found
them elsewhere. There were among them both bivalves and
univalves; of the last, one of the Trochus genus was peculiar,
from being flattened.

The

438 ON THE GEOLOGY OF THE

The ironstone which occurs along with this, is of no great
consequence, nor perhaps very general : it is not converted to
any useful purpose, so far as I could learn.

There is another substance which occurs here and there
among the beds of the second limestone, analogous to the mu-
latto limestone of Antrim, which 1 believe to be a compound
of carbonate of lime and granular augite, similar to the coccolit
of Andrada, but much finer in the grain. In both, the colour
is dark green, and when the calcareous matter is separated by
’ means of acid, the coccolit remains in minute dark-coloured
grains. In Ireland, however, it occurs in more regular strata, _
and of considerable extent, always under the white limestone,
and with the grains of augite pretty uniformly dispersed
through it. Here the beds appear to be mere adventitious
deposites, maintaining no conformity with the accompanying
strata, extremely irregular, and of small extent. Sometimes
they are entirely composed of the coccolit, when they are of a
very dark green colour, and very friable: in this state, the sub-
stance is used in the manufacture of Pigments. It is generally,
however, dispersed through the limestone, in which state it forms
a very beautiful rock. ‘Here, as well as in Ireland, it usually
contains organic remains; besides some bivalves, the belem-
nite, the cornu ammonis, and the nautilus, are the shells which
I have generally seen in it. It assumes positions high and
low, and may be considered an independent member of the
Second Limestone Formation.

There is another variety of limestone, evidently of a subse-
quent date, which also occurs in this vicinity, but on so small
a scale, that it is scarcely deserving observation. In one place
only I noticed it on the road leading from Nice to Ville Franche,
where it lay in thick beds of a soft earthy texture, and con-
taining a quantity of vegetable remains. It is of a green-
ish-grey colour, and probably a species of calcareous tuffa,

which,

ENVIRONS OF NICE. 439

which, in a country so entirely. composed of limestone, is a
very common production.

Some deposites of gypsum likewise present themselves : it is
of the amorphous foliated kind, and, like that of Compostello, a
good deal stained with hematitic iron, but containing no crystals
of quartz. ‘The most considerable bed is one in the immediate
neighbourhood of Nice: it rests on the southern extremity of the
hill of Cimiez, and to the north, it abuts on the first limestone.
Over it there is little else but vegetable mould. I however
noticed some traces of the mulatto stone, which would induce
ene to consider it as a member of the second limestone. I
cannot, however, determine the point, as I nowhere saw it laid
open sufficiently.

Such are the materials, not alluvial, of which this interesting
country is composed. A good deal of the limestone which I
remarked in the south of France, between Aix and the Var, .
appeared to me, in passing rapidly over it, to be of the same
kind as that which I have here denominated the jist, and
which I was induced to consider as belonging to the Transition
series. On this point, however, I speak with diffidence, as I
have had but very little opportunity of remarking its relations
in combination with any apparently older or contemporaneous
rock. In quitting the country by way of the Col de Tende,
very shortly after leaving Nice, I did not perceive, excepting
in two mountains, and there only from a distance, any traces
of my first limestone: the whole countr y was taken possession

_of by the second, ‘which imperceptibly changed its internal -
characters so much, that at Tende, I was for a time induced
to consider it as of the older kind: it always, however, present-
ed a striking difference in its position, being invariably highly
inclined, and in many places contorted in a very remarkable
degree ;—nothing short, in that respect, to the most eccentric
convolutions of the transition rocks of St Abb’s Head.

In

440 ON THE GEOLOGY OF THE

In leaving the village of Tende, to ascend the tremendous
pass of the Col di Cornio, by far the worst of any by which
Italy is entered, the long desired change of rocks presented it-
self, with the limestone of Tende resting in unconformable po-
sition, and so distinct, that there was little possibility of de-
ception. I traced this limestone to the summit of the mountain,
where it rested directly on rocks which appeared to me to be-
long to the transition series ;—from which, if my conjecture be
correct, it is fair to infer, that the first limestone of Nice, is of the
kind I was originally induced to suspect it belonged. It is very
femarkable, however, that in England there is no similar lime-
_ stone that I am aware of; nor do I know any in Scotland or
Ireland which can be classed with it, notwithstanding the great
extent which it occupies in this quarter of the globe.

These few substances comprehend the whole of the rocks, so
far as I had an opportunity of observing, that are to be found
in the vicinity of Nice; but before quitting them, I must again re-
vert to the First Limestone, in order to deseribe the fissures fill-
ed with marine shells, which -prevailed not only in the rock of
Nice Castle, but in the adjacent promontory of Mount Boron. I
name these localities, as it was there only I had an opportuni-
ty of examining them, though I have no doubt phenomena of
the same kind abound throughout the neighbourhood. The
fissures I now talk of, seem to have been formed after the con-
solidation of the brescia, already described, and are literally
filled, in some places, with sea shells, of species all now alive in
the Mediterranean,—a circumstance which suggested to M.
Risso the appropriate name of Marbre Mediterranéene. Many
of these shells retain their pearly lustre and colour; and although
combined in masses, perfectly solid, they preserve their con-
tour and aspect almost as fresh as the day they were deposited.
The fissures which contain these organic remains, are sometimes
partly filled up with solid limestone, without any appearance of

petrifactions,

i LLL ILLS LLL II LLL OLE EL IS LIE SS

ENVIRONS OF NICE. 44]

petrifactions, shewing that the deposition of shells had ceased
and commenced again.

The occurrence of these marine remains proves, in the most
satisfactory manner, that the sea must have flowed greatly
above the level of these rocks, at a time when they were torn
asunder in all directions; and, as if to prove that these opera-
tions had been carried on slowly, I found on the sides of
some of the fissures, since filled up with the Mediterranean
marble, the perforations of the pholas, with the shell of that
animal remaining in its place.

But besides the hills composed of solid materials, there are
others of much importance, whetlier considered as to their ex-
tent, their altitude, or the geological inferences which may be
drawn from their structure and appearance,—I mean those

‘formed of gravel, principally occupying the west side of the

district. When travelling along the banks of the Rhone,
from Lyons to Avignon, I was much struck with the enor-
mous quantity of debris spread over a great proportion of
that line, and all or nearly all belonging to the alpine range
through which this mighty river flows. The debris on the
banks of the Var is of the same nature, composed of masses
of granite, mica-slate, quartz and jasper, pieces of compact
actynolite, and serpentine; but, so far as I perceived, there
were no fragments that could be referred to the trap rocks.
Saussure, § 1428. states, that he saw nothing among the
gravel of the Var but limestone and sandstone; but he had
certainly not examined with his usual acuteness. The hills
formed of this gravel rise with a sharp acclivity from the
plain and the beach, forming a round-backed range, and of an
uniform elevation, but rising gradually from the height of 500
or 600 feet, till they rest high on the sides of Mount Cao.

Looking down upon this mass of alluvial matter from the sum-

Vox. VIII. P. IT. 3K mit

442 ON THE GEOLOGY OF THE

mit of that mountain, it has exactly the appearance of having
once formed a continuous bank, through which the torrents
have cut their way, and produced the numerous beautiful and
picturesque valleys which intersect it in all directions. Of these,
the Var itself may be considered as one; and near its banks,
I have seen cliffs cut in this gravel of at least 400 feet high, and
quite perpendicular. The operations of the various little streams
which occupy the water-courses in wet weather,—for in dry
weather there is little or no water to be seen in them,—are
very remarkable: sometimes I have followed them up, having
barely room to squeeze myself through between the perpendi-
cular walls, and found the cut suddenly terminate in a circular
aperture, like a deep well, into which a little stream precipi-
tated itself. In the Vallon Obscur, the opening is in some
places not more than three to four feet, and the walls rise to
at least 100 feet on each side, fringed at top with shrubs and
trees, often hanging in frightful suspence overhead. Although
there be no regular beds, the general inclination of the gravel
towards the sea, is sufficiently distinct in every cut which runs
in that direction; while in those that are at right angles to it,
the gravel seems to be more horizontally disposed, shewing,
that by some uniform impulse, it had been carried forward in
one constant direction, in the same way as the Var, and other
mountain torrents, transport aoe Sdinpe ame and deposite

them in the ocean.
Unpromising as those heaps of gravel were at first appear-
ance, they afforded another very important lmk in the chain
of facts which this country presents. ‘In the different hills, the
pebbles are bedded in sand, which is more or less abundant.
Deposites of clay are also common ; sometimes they occur on-
ly in small seams, sometimes in thick extensive beds, of at
least 30 to 40 feet. The colour is either of a yellowish drab,
t or

ENVIRONS OF NICE, 443

or a pale bluish-grey ; both are mixtures of argillaceous and
calcareous matter. The former often occurs without the lat-
ter, and when together, it always assumes the uppermost situa-
tion. Of the blue clay bricks and tiles are manufactured, and
I think it might be applied with success to the fabrication of
pottery, as it forms a tough adhesive paste when kneaded with
water, and is of a delicate pale-red colour when burnt.

It is in this particular kind of clay that a considerable varie-
ty of shells are found, of kinds also which are all to be met
with alive in the Mediterranean. A few of them I found in the
most perfect state cf preservation ; but in general they were so
much decomposed, that it was very difficult to withdraw them
from the clay. In almost every valley, these deposites are to
be found, and although some kinds of shells may prevail more
in one than in another, still they are throughout generally the
same varieties, and possess a character peculiar to the clay in
which they occur.

In one situation, where the deposite was simply of sand, and
not many inches thick, I found a great quantity of bivalve
shells, principally pectens, and other small kinds of the ostrea,

_. but not one univalve. In the particular situation I now allude

to, I have no doubt that the shells were in a very recent state,
if not alive, when they were left by the sea. It is true, that
for one unbroken which I found, I threw aside the fragments
of hundreds; yet it seems to be impossible, that shells so deli-
cate and so minute, could submit to the action of transporta-
tion. Besides, the quantity that are here found together, be-
speaks the probability of an original bed. Oysienshend J Have
observed in the same bank, sf so perfect a state, that I could
not have believed them to be any thing but recent, had I not
disengaged them with my own hands. Some of them were
attached to pieces of gravel, not agglutinated by means of cal-

83K 2 * careous

444 ON THE GEOLOGY OF THE

careous cement, but fastened, as they are in the ocean, to the
soil on which they grow.

From these facts, it seems to be quite evident, that these
shells must have been deposited at different periods, during
the tardy formation of the gravel heaps in which they are im-
bedded ; and also, that the heaps must have required a long
time for their accumulation, not only from the growth of the
beds of shells, but from the nature of the materials of which
the hills are composed, and the distance from which these have
been transported. When we consider the time required for
the destruction of the original rocks, and for reducing them
to their present state, it carries the mind back to a period,
compared to which that of history is but a trifle. In the whole
of these operations, we see no marks of hurry and confusion,
no trace of those convulsions which must have preceded
them, previous to the formation of the Mediterranean marble.
On the contrary, from the disposition of the materials them-
selves, and from the extreme delicacy, and state of perfection
in which many of the shells have been found, there is next to
a positive proof, that the accumulation must have proceeded
with the utmost tranquillity, and that these heaps of gravel
must have been carried gradually down, and quietly deposited

in the sea. dw
The shape which they present is also analogous to the na-

ture of the beach in the vicinity of Nice, which, though compo-
sed of loose pebbles, is remarkably shelving, and the sea be-
comes suddenly very deep. Saussure states, that only a league
from the shore, he found 1800 feet of water. Hence, supposing a
turther depression of the Mediterranean, we should just have
such another series of steep acclivities as the gravel banks now
present, the sides and extent of which would in time be fur-
rowed and indented by the running of torrents.

There

' ENVIRONS OF NICE. 445

_ There are other beds containing organic remains which I
consider of subsequent formation to the gravel heaps. The
first of these is on the west side of the Nice plain, and
about a mile from the sea; it is a bank entirely composed of
sand and sea shells. They are principally bivalves, but a
few minute univalves are found among them. Although the
species may be considered the same, the state in which they
occur is quite different from those of the blue clay, and if
we except some large oyster shells, and a few pectens, the rest
are in such a state of decomposition, that it is impossible to
disengage them from the sand.

The second differs from this, but only in respect to the va-
riety of shells it contains; for it is composed of the same kind
of sand. It is situated on the banks of the Paglion, just above
the village of Trinité. Here the sand extends over the sur-
face of a hill, which has been brought into cultivation, and
the. variety of shells contained in it, is immense.. When. these
are turned up by the pioche of the husbandman, and. allowed
' gradually to lose their moisture, they become hard, and are of-

ten found in a good state; in digging for them, however, they
are generally so soft, that it is very difficult to preserve them.
If they can be got out entire, they afterwards attain a slight
degree of hardness; but even in their pulverulent state, they
exhibit their varieties distinctly, and all, I am told, are of kinds
now living in the Mediterranean. Indeed, I have seen most, if
not all of them, in a recent state.
. These two beds appear to form a third epoch in the opera-
tions of the sea-upon the surface of the land; but there is a
fourth, which has all the characters of being still more recent.
This presents itself on the Peninsula of St Hospice, and per-
haps, may involve a question with respect to the point at which "
- shells are to be considered fossil ; many of those which I have
found in this situation, being in such a perfect state, that it is
nearly

~

446 ON THE GEOLOGY OF THE

nearly impossible to distinguish them from the uninjured dead
shells, which are thrown upon the beach. Some of them haye
preseryed their colour, particularly the red ones, so as to de-
ceive any one.

St Hospice is a long narrow peninsula, which from its sin-
gularly fantastic shape, forms a most beautiful feature in the
country, and is, for the most part, covered with olive trees ;
some of these are so large, and present such an aspect of anti-
quity, that they are considered by the country people to be six
or seven hundred years old. The neck by which it is joined to
the mainland is the lowest part of it, and there it may be seventy
or eighty feet above the level of the sea. M. Risso has descri-
bed* a deposite of sea-sand and shells, which was found in ex-
cavating a well in this peninsula, at the height of 20 metres
above the sea-mark. They had only gone down three metres
when the deposite in question was penetrated, which was found
to be five metres in thickness. The shells were here discovered
in such a perfect state, that when Risso presented them as fossil
productions in Paris, his veracity was somewhat questioned.
On the east side of the Peninsula of St Hospice, not three
hundred yards from this spot, on the edge of the cliff, I found
what appears to be a continuation of the above deposite but
here not more than fifteen or twenty feet above the level of
the sea. They lie on a mass of blue clay belonging to the se-
cond limestone, and are either imbedded in a fine white dry
sand, or mixed with a proportion of clayey marl, and in one
place were so abundant, that they may be taken out by the
handful. The bed which contains these shells differs in thick-
ness; in some places it may measure from 12 to 15 feet. The
upper part of it is frequently so indurated, that it requires the

hammer

ee

» Journal des Mines, No. 200.

ENVIRONS OF NICE. 447

hammer to break: it; elsewhere it may be dug into with a
trowel. If carefully looked for, I believe it would be found to
extend over a considerable portion of the peninsula, as, in
walking along the edges of it, 1 have remarked traces of the
same kind of sand, which I have no doubt are continuous.

I look upon this as the last operation of the sea previous to
its being reduced to its present level. Besides the shells and
fragments of coral this bed contains, I found parts of the limbs
of crustaceous animals. '

The last fact 1 have to notice, is not the least interesting,
it is one which has puzzled the ingenuity of all who have
attempted to account for it, and which still requires more
observation in order to be satisfactorily resolved. This coun-
try, as well as many others washed by the Mediterranean, con-
tains different deposites of the bones of animals: these are
usually imbedded in a red indurated clay, forming a mass
which is distinguished by the name of the drésche osseuse.

This conglomerate is already so well known, that it is only
necessary ee me to notice the peculiarities reich occurred to
myself. In this neighbourhood there are three different depo-
sites of it, one at Cimiez, another at Ville Franche, and the third
on the Castle Rock of Nice. The first Ihave never seen. I was
informed that it had recently been covered over with rubbish ; 3.
of the three it is considerably the most distant from the sea.
That near Ville Franche is of very small extent; the paste is
of a lively brick-red colour, and possessed of a preat degree of
induration. The fragments of bones and teeth imbedded in it
are extremely white and along with them are some rounded
pebbles of limestone, and SuediOuaNTY marine shells.. In one
_ part: of the deposite, where there are no bones, or, if any, in-
very minute fragments, the conglomerate appears to be a
congeries of sea shells, mixed with the spines of the Echinus. -

ae At

448 ON THE GEOLOGY OF THE

At the Castle Rock of Nice, the bones occur in two distinct
states ; one forming a very hard indurated brescia, the paste of
which varies from a brown to a colour almost black; in the
other they are loose, or feebly agglutinated, by means of calca-
reous infiltration, with fragments of limestone and sea-shells,
showing that the sea still continued its operations when the re-
volution which occasioned this deposite took place.

That the sea had retired and again risen, or that a wave had
flowed over this quarter, and in retiring had drawn these de-
bris along with it, is most probable, as there appear to be se-
veral fissures very different from those formerly mentioned.
Some containing a few dispersed fragments of bones, and
others nothing but loose earth and stones, and which pro-
bably had been produced ‘by some convulsion long after the
formation of the Mediterranean marble; but at a period previ-
ous to, or perhaps contemporaneous with, the revolution
which brought together the remains of so many different ani-
mals.

On referring to Colonel Imnie’s paper, in the 4th volume of
the Transactions of this Society, it appears that the bone bres-
cias of Nice are in their construction quite analogous to those
of Gibraltar, excepting that they are accompanied with traces
of marine animals ;—while nothing but terrestrial testacea are
noticed as accompanying the other. This forms a striking
distinction between them; but it is one which tends rather to
involve than to elucidate the history of their formation.

Some individuals have been anxious to bring down the ope-
rations of nature in the formation of the rocks in this vicinity,
even-to a period subsequent to the civilization of mankind ; and
SavssurE mentions a story related to him by the French Con-
sul in 1787, respecting a copper nail which was said to have
been found in the heart of a solid mass of limestone. Some-

thing

—_—.

vO ———

——~ CU

ENVIRONS OF NICE 449

thing of the same kind was communicated to me by my friend
Risso, who showed me three or four nails, one of which he
most obligingly presented to me: these he assured me, with
every appearance of conviction, were taken out of the solid
strata in the vicinity of the harbour. We were very often en-
gaged to visit the spot, but it so happered, that something al-
ways came in the way to prevent it, and I left Nice without
being persuaded that the solid stratum was more than the ag-
glutinated shingle of the sea-beach, though the nail will I be-
lieve be allowed to have all the characters of genuine anti-

quity.

I have thus enumerated all the objects which I met with de-
serving of attention in this interesting district ; and although
my observations were extremely circumscribed, still the mate-
rials which this little spot contains, are of much importance in
the geological history of the globe. It may be remarked, how-
ever, that the phenomena which it presents are somewhat pe-
culiar. In most countries, the organic remains are of a nature
totally differing from the living animals which now inhabit
them, proving that great aitemirins must have taken place on
the physical functions, if I may use such an expression, of the
different countries they are found in. In Britain, the skele-
ton of the Alligator, the shell of the Tortoise, and the i impres-
sions of the’ Palm-tree; with which its strata abound ; 3 as well
as the teeth of the Elephant, and the bones of the Mastodon-
ton,’ which have been found in its alluvial deposites, all tend
to shew under what different circumstances that country must
formerly have existed: The marine remains are in the same
predicament : they are rarely, if ever, of the species which occur

_ alive upon its coasts. At no greater distance than the opposite

side of the range of hills which separate the Nice district from
Vou. VIII. P. II. 3L the

450 ON THE GEOLOGY OF THE

the Valley of the Po, we find a marked distinction. Besides
the remains of the animals just mentioned, with those of the
Hippopotamus, the Urus, and the Elk, Broccut has enumera~
ted 284 different shells, many of which are either the inhabi-
tants of distant oceans, or whose prototypes are altogether un-
known; while all the marine fossil remains of Nice may be
found in a recent state in the adjoining sea.

Broccnt, I find, is inclined to dispute the fact of the shells of
St Hospice being really fossil, as stated by M. Risso, in his short
but interesting memoir on that peninsula, and is inclined to con-
sider this spot as the bottom of some former sea. No one,I think,
will dispute the last position; but with respect to the shells being
really fossi/, in a geological point of view, that must, as I have
already stated, depend upon the acceptation of the term: for,
here we trace these marine remains, no doubt deposited at very
different epochs, from a state in which they have undergone
very little alteration, to that of being reduced to an impalpable

powder ; and, finally, we find them imbedded in the solid rock,,

and even in this situation retaining a great degree of colour,

and the pearly lustre among those to which it is peculiar,
In the bone brescia, we certainly find the remains of land
animals no longer existing in Kurope: still the state of the
marine organic remains shews, that the changes which have so
strangely affected other countries, do not appear to have ope-
rated on this; and they likewise prove, in the most incontes-
tible manner, the great alteration which has taken place on the
relative position of the sea and land... How this, alteration has
been brought about, I shall not pretend to, discuss: it is, an
investigation somewhat analogous to that of the original, for-
mation of the Globe, or, as it is more modestly ae the
Crust of the Earth, not very likely to be rewarded by any satis-
factory

Daan ta oss onk dliochectseosa.atth sa

eae

ee

ENVIRONS OF NICE. 45)

factory result. I may simply notice, however, that while
Broccnr contends that the waters of the Mediterranean have
been allowed to escape by the opening of the Strait of Gibral-
tar, he combats the hypothesis entertained by Russo, founded on
the traditions recorded by Srraso, that the influx of the Euxine,
when it first broke its way into the Mediterranean through the
Thracian Bosphorus, elevated the level of the Mediterranean,
while it was yet separated from the ocean. That such an event
might have caused an immense wave to have inundated the
adjoining coasts, is most probable; but its influence would be
very transient ; for all the water that could have been drained off
from the Caspian and the Euxine united, by the occurrence of
such a catastrophe, unless we are to suppose them to have been
far more extensive than they are at present, would have very
little influence on a space of such immensity as the Mediter-
ranean.

One thing, however, appears very clear, that the alteration
of the relative levels has not been occasioned by the elevation
of the land, subsequent to the deposition of the gravel beds,
whatever may have happened previous to that period. The
characters of these alluvial heaps, on which I found my ar-
guments, are entirely distinct from those of the transition and
floetz rocks, whose territories are so often invaded by the gra-
nite and trap formations, and elevated with every appearance

of violence and agitation. The beds of gravel, on the contrary,
have undergone no alteration, excepting where furrowed by
the action of surface-water, since their original deposition.
They appear to have been left exactly in their present situa-
tion, and exactly in the same way as the debris brought down
by the continuation of the same process still continues to be,
and bear the most satisfactory marks of having remained ever

_since in a state of perfect quiescence.
3L2 As

452 ON THE GEOLOGY OF THE ENVIRONS OF NICE.

As the formation of these gravel meee still continues &
proceed before our eyes, it would form a very curious subject
of speculation, if the progress of the n mounds which are evi-
dently projecting by every river which pours itself into the |
Mediterranean, could be ascertained. It would be curious to
learn what period of ‘years was required to make any sensible
difference on the soundings at the embouchure of the Var, and
although much allowance would require to be made, still ac-
curate observations of this sort would afford some data, by
which the probable period requisite for the formant of the
banks above might be computed. ,

APPEN-

PLATE vit.

Engraved: tor the Royal Soctely Tran Vol.Vil. Payot 52

Scale of Miles

i Lime Stone____ Pink
"Lime Stone -__--
Gravel_________ Brown
Gypsum ...._---Yellow

ENVIRONS
of

Nict&
Engraved for the Transactions
—— of the -
Royal Society of Edin?

by W.&D .Lizars.

i ee err
f

APPENDIX.

Ix the preceding sketch, I have had frequent occasion to refer
to the wonderful diversity of Fossil Shells,which presented
themselves in different quarters of this interesting country ;
but in order to. preserve connection, I have refrained from
mixing up. with the text, the description of them, when: de-
scribing the different localities in which they occurred ; and I
am the more satisfied with having done so, because, with the
assistance of Captain Brown, who has already so»greatly distin-
guished himself as a conchologist, I am enabled to present to
the Society a very distinct, and,. I trust, what, will be found to
be a very: interesting account, of these fossils. And as te
testimony. to ales, acuteness, the unwearied and anxious per-
severance with which that gentleman prosecuted his investi-
gations, on objects truly, microscopic, sparing neither time nor
troubles in chiphre himself of the accuracy of his observations,
shied me of pin which he sage new, together with a very
correct, drawing (see Pl. X. fig.8.) of the specimen from. the
summit of Mount Cao, mentioned in the text, of which I have
had occasion to take so much notice. | I requested him to. make
this drawing, in order to preserve a specimen, that I fear,
has every chance of being unique; a merit which, however
gratifying to the self-love of the mere collector, does not add
to its value in a geological cabinet. A faithful and accurate
engraving is the only means of remedying this evil.

All

454 GEOLOGY OF THE ENVIRONS OF NICE.—APPENDIX.

All the shells described in the following catalogue, are si-
milar to those, though not in so high a state of preservation,
which were found so abundantly some years ago at Grignon
in France, and which abound in various parts of that country,
as well as in Italy. For the most part, they are exceedingly.
minute, many of them requiring the power of a solar micro-
scope to determine their characters with precision.

The whole number enumerated amounts to two hundred
and twenty-five; of these, thirty-three species, which Captain
Brown considers new, he has particularly described and figu-
red. He has also described two new madrepores. Among
them are some odd valves of a new Chiton, a genus not even
noticed by Broccut, in his Conchologia Fossile Subapennina :
likewise several of the Haliotis striata ; a genus also unknown,
‘or at least not included in’the work above quoted; so that all
the Linnean Genera have been found in this neighbourhood
except the Argonauta.

For the sake of brevity, Captain Brown has confined his re-
ferences to the latest authority for description, and the best
for the figure of the shell.

Together with the engravings of these fossil remains, I have
given a small Map of the Environs of Nice. This is principal-
ly taken from a manuscript map in the possession of Mr Ris-
so, in some degree corrected and verified by the rough obser-
vations I was able to make with one of ScumMaxcaLpEr’s milita-
ry compasses, an instrument of sufficient accuracy for the pur-
poses I required. It will be satisfactory to the reader to ob-
serve the bearings of the different localities ; and the colouring
of the map will enable him to distinguish the extent of the
different formations and deposites I have had occasion to de-
scribe.

ENVIRONS OF NICE.— APPENDIX.

I.

Fosstu Suetts found in the Sand and Clay, among the Grayel Heaps formed
by the detritus of the Primitive Rocks of the Alps which front the left bank of the
Var, and extend along the west and north sides of the Plain of Nice, coloured

brown in the annexed Map.

MULTIVALVE.

LEPAS.
a. Balanoides. Dillwyn’s Conch. p. 16.—Do-

Br. Sh. I. 36.

novan,
f. 2.

t.

BIVALVE.

MYA. iy
1. nquivalvis. Montagu, Test. Br. p. 38. t. 26.

f."7.—Dillwyn’s Conch. p.55.

TELLINA.
1. divaricata. _Wood’s Conch. p. 195. t. 46.
£.6.—Dillwyn’s Conch. p.102.
2. gibba. Brocchi, p. 516.—Encyc. Meth.
t. 230. f. 4.
CHAMA.

1. coralliophaga? Brocchi, p. 525. t. 13. f. 10.
o
ARCA.

1. granosa. Linné, Syst. Nat. p. 1142.—Lis-
ter’s Conch. t. 241. f. '78. and
t. 242. f.'79.—Dillwyn’s Conch.

. 235.

2. didyma. Brocchi, p. 479. t. 11. f. 2.

_ OSTREA.
1. strigilata. Brocchi, p. 571. t. 14. f. 15.

novan, Br. Sh. i. t.12.; O.sub-
rufa.—Dillwyn’s Conch. p. 266.

3. Jacobea. Limné, Syst. Nat. 1144.—Dono-
van, Br. Sh. iv. t. 137.—Dill-
wyn’s Conch. p. 248.; Testa
junior.

4. edulis. Lmné, Syst. Nat. 1184.—Pen-

nant, Br. Zool. iv. p. 104. t. 62.
f.'70.—Dillwyn’s Conch. p. 280.
5. pleuronec- Linné, Syst. Nat. p. 1145.—

tus. Rumphius, t. 45. f. A. & B.—
Dillwyn’s Conch. p. 250.
6. Lima. Encyc. Method. t. 206. f. 4&
Lima squamosa.—Dillwyn’s
Conch. p. 271.
ANOMIA.

1, Squamula. Encyc. Method. t. 171. f. 6.
and 7.—Maton and Racket,
in Lim. Tr. vii. p. 103.—
Montagu’s Test. Br. p. 156. &

2. opercularis. Linné, Syst. Nat. p. 1147,—Do- 561.
. ) . UNIVALVE.
NAUTILUS. * ih. BUCCINUM.
‘1. Beccari. Montagu, Test. Br. p. 186.; cf | 1. musivum. Brocchi, p. 340. t. 5. f. 1.
MOG sup. p. 74. t. 18. f. 4.—Dill- | 2. serratum. Brocchi, p. 338. t. 5. f. 4.
Peaip cpank wyn, p. 342. 3. corniculum. Brocehi, p. 341. t. 15. f. 15.
BULLA. ,

_1. cylmdri-- Donovan, Br. Sh- iv. tab. 120.

a3

cea. f. 2.—Dillwyn’s Conch. p. 496.
“2. ampulla. ~Linné, Syst. Nat. p. 1183.—Lis-
vee ter’s Conch, t. 718. f. 69. &
hin t. 1056. f. 8. —Dillwyn’s Conch.
ia p- 479. °
8. lignaria. Linné, Syst. Nat. 1184.—Lister’s
, le Conch. t. 714. f. 71.—Dillwyn’s
OG Oe Conch. p. 480.
VOLUTA. :
°L buceinea.’ * Brocchi, p.'319. t. 4. f. 9.

9,
th

“dandestina. Brocchi, p. 642. t. 15. f. 11.

MUREX.
1. turricula.. Montagu’s Test. Br. p. 262. t. 9.
f. 1.—Dillwyn’s Conch. p. 744. ¢
2. dimidiatus. Brocchi, p. 491. t. 8. f. 18.
8. thiara. Brocelu, p. 424. t. 8. f. 6.
4. pustulatus. Brocchi, p. 430. t. 9. f. 5.
5. sutura. Shell oblong, with longitudinal
Pl. X.f. 7 ribs; and strong transverse and
waved obsolete longitudinal
strie. 'The suture is broad, and
stnated longitudinally; with a
strong double line in its centre.

Pillar-

456 GEOLOGY OF THE

Pillar-lip smooth, and not re-
flected. Spire with 10 volu-
tions; length 1} inch.

6. monile. Brocchi, p. 432. t. 8, f. 15.
TROCHUS.

1. elegans. Gmelin’s Linné, p. 3581.—Schree-
ter, Einl. i. p. 682.—Zorn Na-
turf. vii. p. 167. t. 2.f D1. &
D. 2.

TURBO.
1. clathratu- Montagu, Test. Br. p. 297.; and
lus. oe p- 124.—Pennant’s Br.
Zool. iv. p. 129. t. 81. #111. A.

—Dillwyn’s Conch. p. 854.
Linné, Syst. Nat. p. 123'7.—Do-
novan, Br. Sh. 1. t. 28.—Dill-
wyn’s Conch. p. 854.
8. elegantissi- Dillwyn’s Conch. p. 856.—Do-
mus. novan, Br. Sh. v. t. 179. f. 1.
4, eonoideus. Brocchi, p. 660. t. 16. f. 2.
5. aculeatus. Shell imperforate, turrited, with

2. clathrus.

Jutions seven; apex pointed.
This shell is very like the T.
clathrus, but may easily be dis-
tinguished, from the ribs being
crowned with spines.

6. tenebrosus. Maton and Racket, in Linn.
Trans. VIII. p. 160.—Mon-
tagu, Test. Br. p. 303. Sup.
t. 20. f. 4.

HELIX.
1. subulatus. Dillwyn’s Conch. p. 881.—Dono-
van’s Br. Sh. V. t. 172.
2. Haliotoi- Linné, Syst. Nat. p. 1250.—Lis-
dea. ter’s Conch. t. 570. f. 21.—Dill-
wyn’s Conch. p. 973.
NERITA.
1. Canrena. Linné, Syst. Nat. p. 1251.—Lis-
ter’s Conch. t. 560. f. 4.—Dili-
wyn’s Conch. p. 975.
DENTALIUM.
1. Entalis. Linneus, Syst. Nat. p. 1263.—
Dillwyn’s Conch. p. 1065.-Do-
novan, Br. Sh. p. 48.—Mon-

Pl. X. f. 9. sub-contiguouswhirls, and thick tagu, Test. Br. p. 494.
longitudinal distant ribs, crown- | .-coarctatum. Broechi, p. 264. t. 1. f. 4.
ed with inflected spines. Vo-
Il.
Foss SHELLs found.in the Banks of Sand at La Trinité, and on the west side of the
‘Plain of Nice.
BIVALVE.
MYA. 3 striata. Shell elliptical, with strong trans-

1. inequival- Montagu’s Test. Br. p. 38. t. 26. | Pl. IX. f. 12.

vis. f. '7—Dillwyn’s Conch. p. 55.
—Maton and Racket in Linn.
Trans. vil. p. 40. t. 2. f. 6.
2. Trinitéa. Shell ovate, depressed, umbo a
PL IX. f. 3. _ little turned to one side: pos-
terior slope somewhat truncat-
ed; with strong regular con-
centric ridges, which terminate
with a serrated appearance on
the posterior slope. Hinge with
one strong elevated tooth, which
fits into a socket in the oppo-
site valve, with a lateral tooth
in the anterior slope, and a
groove in the posterior ; length
4ths of an inch, breadth 24
eighths.

verse striz: hinge with an ob-
lique tooth and small socket.
Posterior end somewhat round-
ed; anterior end more pointed :
inside smooth, with strong mus-
cular impressions. Length 1

eighth, breadth 23.

4. undulata. Shell sub-rotund, beak sharp, and

Pl. 1X. f. 13. much turned to one side: hinge
with a deep groove, in which
the cartilage is fixed: posterior
slope somewhat pentane an~
gular. Inside with strong lon-
gitudinal obsolete strie, which
terminate about an eighth of an
inch from the base: the mar-
gin is smooth, with a strong
transverse groove. Outside

smooth,

——

——

ENVIRONS OF NICE.—APPENDIX.

smooth, with wide, transverse
obsolete wrinkles. Length §ths
of an inch, breadth the same.
There is a variety of this shell
more oblong, measuring {ths in
length, and 54 eighths in
breadth.
TELLINA.
1, rotundata. Montagu, Test. Br. p. 71. t. 2.
f. 3.—Dillwyn’s Conch. p. 99.
2. Radula. Montagu, Test. Br. p. 68. t. 2.
f£1.& 2.—Dillwyn’s Conch,
p- 194. Venus spuria.
Montagu, Test. Br. p. 70. t. 2
f. 4.—Dillwyn’s Conch. p. 99.
Shell sub-orbicular, with the pos-
terior slope considerably pro-
duced: umbo turned a little to
one side: hinge with two cen-
tral teeth, one ° of which i is con-
siderably Tan ger than the other,
and bifid; and with two remote
' lateral teeth : margin obtuse,
¥ and slightly crenulated. Ex-
terior surface covered with lon-
‘gitudinal and transverse strie,
which has much the appearance
of afile. Length 43 eighths,
breadth 54 eighths of an inch.
Gmelin’s Linné, p. 3238.—Do-
_ novan, Br. Sh. v. t. 163.—Ma-
ton and Racket, in Linn. Tr.
51.—Dorset Cat. p. 30.
t.5. tbe —W 00d’s Conch. p.171.
t. 45. f. 3.
Tellina squalada, Solanders’
MSS. Seiten; Dorset Cat.
p- 29.—Montagu, Test. Br.
p. 56.—Gualtieri, t. 88. f. L.
—Cheania v t. 10. f. 96.

3. lactea.

4. tigerina.
Pl. IX. f. 11.

5. depressa.

he Pinar

CARDIUM.
1 et, Brocchi, p. 666. t. 16. f. 11.

nadeak :

1. truncata. Donovan, Br. Sh. iv. t. 126.—
Fleming, in Edin. Encyc. art.
- Conch. p. 93. pl. 205. f 14.—
Davey, Conch. p. 140.

VENUS.

1. verrucosa. Donovan, Br. Sh, ui. t. 44, —Dill.
wwyn’s Conch. p . 164.

2. Paphia. _Linné, Syst. Nat. p- 1129.—Lis-
ce Conch, t..279. f. 116.—

n’s Conch. p. 159.
Vou. VIL EL 7

457

3. ovata. Maton and Racket, in Linn. Tr.
vil. p. 85. t. 2. f. “4. —Dillwyn’s

Conch. p. 171.
3. gallina. Donovan, Br. Sh. i. t. 68. V. stria~
tula.—Dillwyn’s Conch. p. 168.
5. pectun- Gmelin’s Linné, p. 3287.—Broechi,
culus. Fossile subappennina, p. 560.

pl. 13. f. 12.—Dillwyn’s Conch.
p- 184.

6. incrassata. Brocchi, p. 557. pl. 14. f. 7.

7. Islandica. A variety, of an elliptic form, and
more ventricose, than the com-
mon species.—Brocchi, p. 557.
pl. 14. f. 5.

8. senilis. Brocchi, p. 539. t. 13. f. 13.
9. dysera. Linné, Syst. Nat. 1130.—Lister’s
Conch. t. 277. f. 114.—Dul-
wyn’s Conch. p. 161.
CHAMA.

l.calyculata. Encye. Method. t. 233. f. 6.—
Dillwyn’s Conch. p. 217.
2. pectuncu- Dillwyn’s Conch. p. 220.—Lis-
lus. ter’s Conch. t. 347. f. 185.
3. antiquata. Linné, Syst. Nat. p. 1138.—Lis-
ter’s Conch. t. 346. f. 183.—
Dillwyn’s Conch. p. 215.

4, gigas, Linné, ae Nat. p. 1137.—Lis-
ter’s Conch. t.351. f. 189. a. &
t. 352. f. 189. 6.—Dillwyn’s
Conch. p. 213.

5. Lazarus. Encye. Method. t. 197. f. 1—
Dillwyn’s Conch. p. 221.

ARCA.
1, pilosa. Mae and Racket, in Linn. Tr.
. 94. 3. f. “4,—Dillwyn’ s
Beck. p- 242.
2. Glycyme- Maton and Racket in Linn. Tr.
Tis. vii. p. 93. t. 3. f. 3.—Dillwyn’s
_ _ Conch, p. 241.

3. nucleus. Of a large size, measuring 33 of
an inch in breadth.—Donovan,
Br. Sh. ii. t. 63. —Dillwyn’s
Conch. p. 244.

4, didyma. See p. 29.

5. nitida. Brocchi, p. 482. t. 11. f. 3.

6. granosa. Linné, Syst. Nat. p. 1142.—Lis-
ter’s Conch. t. 241. f. '78.—Dill-
wyn’s Conch, p. 233.

7. minuta. Montagu, Test. Br. p. 140.—Do-
novan, Br. Sh. ii. t. 78. Arca
caudata.—Dillwyn’s Con. p. 245.

OSTREA.

1. pleuronectus. Vid. p, 455.
2. opercularis. Vid. p. 455.
3. strigillata. Brocchi, p. 571. t. 14. f. 15.
4, Jacobea,

458

GEOLOGY OF THE

Maton and Racket in Linn. T'r.
; vii. p. 103.—Montagu’s Test.
' Br. p. 156. & 561.

UNIVALVE.

4. Jacobea. Vid. p. 455.

5. areuata. Brocchi, p. 578. t. 14. f. 11.
ANOMIA.

1, Squamula. Encyc. Method. t. 171. f. 6. & 7.
NAUTILUS.

1. calcar. Linné, Syst. Nat. p. 1162.—Gual-

tier, t. 19. f. C.—Dillwyn’s
Conch. p. 340.

Montagu, Test. Br. p. 186. ; and
Supp. p. 74. t. 18. f 4.—Dill-
wyn, p. 342.

3. depressu- Montagu, Test. Br. Supp. p. 78.

lus. t. 18. f. 9.—Dillwyn’s Conch.
p- 341.
4, levigatu- Montagu, Test. Br. Supp. p. 5.

2

. Beccarii.

lus. t. 18. f. 7. & 8—Dillwyn’s
Conch. p. 341.
5. Rapha- — Limné, Syst. Nat. p. 1164.—Gual-
nus. tieri, t. 19. f. L, M.
CONUS.

1. Mercati. Brocchi, p. 287. t. 2. f. 6.

VOLUTA.
1. suborbiculata. Brocchi, p. 317. t. 4. f. 3.

2. buccinea. ets p: = oi See
3. episcopalis. illiwyn’s Conch. p. ——Ts=
Pye fe toanke 839, f. 66.

BUCCINUM ‘
1. prismaticum. Broccht, p. 337. t. 5. £.7.
2. marginatum. Brocchi, p. 332. t. 14 f. 17.
Testa junior.
Brocchi, p. 344. t. 5. f. 10.
Linné, Syst. Nat. p. 1206.—
Lister’s Conch. t. 837. f. 64.
—Dillwyn’s Conch. p. 648.

3. poly ‘onium.
4. DeeitGint

5. gibbosu- Encye. Method. p. 280.—Lister’s
jum. Conch. t. 973. £. 28.—Dillwyn’s
Conch, p. 605.
STROMBUS.

1. Pes pelecani. Linné, Syst. Nat. p. 1207.—
Donovan, Brit. Sh. I. pl. 4.
—Dillwyn’s Conch. p. 656.
2. Pugilis. Dillwyn’s Conch. p. 664.—Gual-
tier, t. 32. f. 13.
MUREX. :
1. distortus. Brocchi, p. 399. t. 9. f. 8.
2. angulous. Brocchi, p. 411. t. 7. Tall
3. dimidiatus. Vid. p. 455.
4. contiguus. Brocchi, p. 433. t. 9. f. 14
6. triplicatus. Brocchi, p. 435. t. 9
rex turricula.

7. granulosus. Brocchi, p. 449. t. 9. f. 18.

8. Lingua. Chemnitz, x. p. 251. t. 161.
f. 1340, & 1341.—Dillwyn’s
Conch. p. 688.

9. pustulatus. See p. 455.

TROCHUS.
1. perspectivus. Linnzeus, Syst. Nat. p. 1227.
—Lister’s Conch. t.636.f.24.—
Dillwyn’s Conch. p. 784.
2. zizyphinus. Linné, Syst. Nat. p. 1231.—
Donovan, Br. Sh. IT. t. 52.-

Dillwyn’s Conch. p. 799.
3. elegans. Dillwyn’s Conch. p. 807.—Zorn
: Naturf. VII. p. 167. t. 2.
; f. D. 1. and D. 2.
TURBO.
1. triplicatus. Brocchi, p. 369. t. 6. f. 14.
2. vermicularis. Brocchi, p. 872. t. 6. f. 13.
$. acutangulus. Brocchi, p. 368. t. 6. f. 10.
4. clathrus. Vid. p. 456.

5. elegantissimus. Dillwyn’s ‘Conch. p. 856.—
Lor Br. Sh.v. t. 179.
aL
Dillwyn’s Conch. p. 829.—Lis-
ter’s Conch. t. 647. f. 41.

6. rugosus.

NERITA.

1. Canrena. Vid. p. 456.

2. Glaucina. Dillwyn, p. 978.—Donovan, Br.
Sh. I. t. 20. & 1.—Gualtieri,
t. 67. f. & B.

HALIOTIS.

1. striata. Dillwyn’s Conch. p. 1010.—Martini’s

Conch. I. p. 179. t.14. £138.

DENTALIUM.

1. Entalis. Linnezus, Syst. Nat. p. 1263.—
Dillwyn’s Conch. p. 1065.—Do-
noyan, Br. Sh. p. 48.—Monta-
gu, Test. Br. p. 494.

2. rectum. Gualtieri, t. 10. f. H.—Gmelin’s
Linné, p. 3738.—Dillwyn’s Con.
p. 1063.

3. Elephan- Linné, Syst. Nat. p. 1263.—Lis-

tinum. ter’s Conch. t. 547, upper fig. 1.
—Dillwyn’s Conch. p. 1064.

Ill.

ee

EN Er a ne

ENVIRONS OF NICEs—-APPENDIX. 459

III.

‘Fossit Tzstacza found on the Peninsula of St Hospice.

MULTIVALVE,
TON. longitudinally ; length about six-
eight rted Shell very convex, valves strongly eighths of an inch,
Pl IX. f.1. suleated concentrically ; the ante- Only two anterior, and one po-,
ba rior valve rising into aknob. The sterior valve of this shell were
upper part of the shell is foliated found.
BIVALVE.

—Brocchi, p. 512. t. 12. £. 5.
T. subcarinata.
2. rotundata. Vid. p. 456.
3. densus. Shell greyish-white, sub-orbicu-
PL. IX.f. 6. lar, smooth, gibbous, and pel-
lucid. Hinge with two teeth,
and an internal groove in which
the cartilage is fixed. Length
§ths, breadth the same. It
is a strong and rather convex
shell ; resembling the tellina
lactea, but differing from it in
eing much stronger, smoother,
and the umbo being nearer the
centre.
4. lactea, Vid. p. 456.
5. divaricata. Vid. p. 455.
6. radiata. | Wood’s Conch. p. 158. t. 38. f. 2,
& 3.—Dillwyn’s Conch. p. 83.
7. dentata. Wood's Conch. p. 195. t. 46. f. 6.
—Dillwyn’s Conch. p. 102.
8. obsoleta. Shell ovate, anterior end some-
PI.IX.f.7 what angulated, posterior end
rounded, convex, pellucid, and
glossy, with transverse, sharp,
minute ridges; and a bifid pri-
mary tooth in each valve. The
left valve with lateral teeth,
Outside wine-yellow, with nu-
merous, divergent, obsolete rays
of a cream-yellow, which be-
come darker as they approach
the base. Inside glossy, with
a large spot of Sray-yellodt
Mr Autan found a recent |
specimen of this beautiful shell |
in the Mediterranean, at Nice. |
PLIX-£S. In the recent species, the rays
. are

MYA. yh sa }
1. elongata. Shell concentrically wrinkled, and

.f,2. withlongitudinal divergent striz.
Pie ae Hinge we a large, broad, ele-
vated tooth in the left valve;
right valve with a small tooth
and socket; into which the tooth
of the opposite valve fits. Umn-
bo plnceet very much to one side.

. Trinitéa. Vid. p. 456.
4 sinuosa. Shell somewhat wedge-shaped and
pl. IX. f. 4. truncated on both ends; page
with a small tooth. Obsoletely
? wrinkled, with a waved margin.
Length ?ths, breadth §ths of

: an inch. ¥

4. punctatus. Shell somewhat triangular, de-
PLIX.f5. pressed, very glossy, sub-pellu-
cid, diaphanous, and smooth ;
' " with obsolete concentric wrinkles;
towards each end, it is very
finely punctured, but perfectly
smooth in the centre; left valve
with one central and one re-
mote tooth; right valve with
“two central and one remote
tooth. Umbo sharp, and turn-
ed to one side. ‘There is a
slight triangular depression,
commencing about the venter,
and terminating at the base.
Length iths of an_ inch,

5 breadth 4.
5. mzequivalvis. Vid. p. 456.

TELLINA.
1. Donacina. Montagu, Test. Br. p. 58. t. 27.
f. 3.—Dillwyn’s Conch. p. 89.

3 2

460

are of a brownish lake-red at
the base of the shell, and be-
come of a straw-yellow as they
ascend, and loose themselves at
* the umbo; which is of a pale
gallstone-yellow. In the inside
is a large blotch of saffron-yel-
low; the rays are distinctly
seen through, and deepen as
they approach the base.
This shell, as well as the
following species, would be pla-
- eed in Lamarck’s genus Lu-
cina.
9. tigerina. Vid. p. 456.
CARDIUM.
tuberculatum. Wood’s Conch. p. 210. t. 50.
f.1, & 2.-Dillwyn’s Conch.
p. 117.

2. multicostatum. Brocchi, p. 506. t. 12. f. 2.

3. planatum. Brocchi, p. 506. t. 13. f. 1.

4, punctatum. — Brocchi, p. 666. t. 16. f. 11.

MACTRA.

1. triangula. Brocchi, p. 535. t. 13. f.-'7.

2. lactea. Shell ae milk-white, smooth,

PI.IX.f. 9. glossy, and obsoletely stria-
ted. Hinge with one small
tooth, and a spatuliform ca-
vity. Length 3th of an inch,
breadth §ths.

This shell somewhat re-

sembles the M. Boysu.

3. solida. Donovan, Br. Sh. II. t. 61.—

Dillwyn’s Conch. p. 140.

4, subtruncata. Maton & Racket, in Linn. Tr.
VIEL pil. 1 1 ei
Dillwyn’s Conch. p. 141.

5. Boysii. Montagu, Test. Br. p. 98. t. 3.
f..'7.—Dillwyn’s Con. p. 143.
DONAX.

1. trunculus. Donovan, Br. Sh. I. t. 29. f. 1.-
Dillwyn’s Conch. p. 150.

VENUS.
1. verrucosa. Vid. p. 457.
2. compressa. Montagu, Test. Br. Supp. p. 43.
t. 26. f. 1.—Dillwyn’s Conch.
p- 167. V. Montagui.

Vid. p. 457.

Donovan, Bnt. Sh. I. t. 17.—
Dillwyn’s Con. p. 178.

3. gallina.
4, Chione.

GEOLOGY OF THE

5. exoleta. Maton and Racket, in Linn.
Trans. VIII. p. 87. t. 3. f. 1.-
Dillwyn’s Conch. p. 195.

6. virginia. Maton and Racket, in Linn.

Trans. VITF. p. 89. t. 2. f. 8.—
Dillwyn’s Conch. p. 207.
7. subrhom- Montagu, Test. Br. Supp. p. 49.

boidea. ty 28ei ee

8. fasciata. Donovan, Br. Sh. V. t. 170.—
Dillwyn’s Conch. p. 159.

9. distorta. Shell oblong, with concentric

PLIX.f. 10. folds, and fine, regular, diver-
gent striz. Hinge with two
teeth in each valve, and lateral
grooves in the anterior slopes.
The margin is irregularly
wrinkled.

SPONDYLUS.

1. gaedaropus. Lister’s Conch. t. 206. f. 40. to
209. f. 3.—Rumphius, t. 47.
f, E.—Dillwyn’sConch. p.209.

CHAMA.
1. calycatula. ‘Vid. p. 457.
2. pectunculus. Vid. p. 457.

3. Lazarus. Vid. p. 457.
ARCA.

1. Now, Gualtieri, t. 87. f. H.—Dillwyn’s
Conch. p. 226.

2. barbata. Gualtien, t. 91. f. F.—Dillwyn’s
Conch. p. 229.

3. lactea. Donovan, Br. Sh. IV. t. 135.—
Dillwyn’s Conch. p. 236.

4. nummaria. Brocchi, p. 483. t. 11. f. 83—

Lister’s Conch. p. 239. f. 81.
—Dillwyn’s Conch. p. 243.

5. angulosa. Lister’s Conch. t. 245. f. 76.—
Dillwyn’s Conch. p. 240.

6. Glycymeris. Vid. p. 457.

7. pilosa. Vid. p. 457.

8. nucleus. Donovan, Br. Sh. IT. t.63.— |
Dillwyn’s Conch. p. 244.

OSTREA.
1. ‘varia. Donovan, Br. Sh. t. 1. f. 1.—

Dillwyn’s Conch. p. 260.

gy Encyc. Method. t. 214. f. 1.

3. sanguinea. Encyc. Method. t. 214. f. 4.—
Dillwyn’s Conch. p. 269.

4. Lima. Vid. p. 455.

ANOMIA.

ENVIRONS OF NICE.—APPEN DIX.

ANOMIA.
1. Ephippium. Donovan, Br. Sh. I. t. 26.—
Dillwyn’s Conch. p. 286.
2 undulata. Donovan, Br. Sh. II. t. 45. O-

strea striata—Dillwyn’s Con.

461

MYTILUS.
1. striata. Shell concentrically striated. ««
Only a broken valve of* this.
shell was found, which renders it
impossible to give any further

p. 289. characters. It, however, has eve- *

. . Vid. p. 457. ry appearance of having, been

lig s aps 5: formed like the M. eda

UNIVALVE.
NAUTILUS. : 3. nebulosa. Shell tapering and smooth, .
1. erispus. Montagu, Test. Br. p. 187. t.18. | Pl IX.£16. clouded with pale chesnut ;
f. 5.—Dillwyn’s Con. p. 341. spire prominent, being in
2. Balthicus. Schroeter Einleitung, I. p. 20. length about equal to thebody;
t. 1. f. 2:—Dillwyn’s Con. p. 342. columella, with four knobs. or
3. depressu- Montagu, Test. Br. p. 190.t. 18. teeth.

lus. f. 9.—Dillwyn’s Con. p. 341. 4. acuta: Shell transversely striated ; body

4, Beccarii.. Vid. p. 458.

CONUS. ‘
1. ponderosus. Brocchi, p- 293. t. 3
2. deperditus, Brocchi, p. 292, t. 3.
3. Aldoverandi. Brocchi, p. 287. t. 2
4, turricula. Brocchi, p. 288. t. 2.
5. pelagicus. Broechi, p. 289. t. 2:
6. coronatus. Encyc. Method. T. 322. f.2—
Dillwyn’s Conch. p. 403.

Sei
f. 1.
. f. 5.
f..7.
f. 9.

CYPREA. ae
1. Euro Montagu, Test. Br. Sup.
ssi spite Br. Shells, I. t.43.
Cypreea pediculus.—Dillwyn’s
Conch. p. 467..

BULLA.
1. ovulata. Brocchi, p. 377. t. 1. f. 8. a..
2. retusa. Montagu, Test. Br. p. 223. t. 7.
neo Te 5.-B. truncata, Dillwyn’s Conch.
Pp: he Meer i

VOLUTA. :
1. quadruplicata. Shell’ yery minute, oval,
PLIX. £.14. smooth ; columella with
four plaits, aperture linear
outer lip toothed; spire
not visible.
2. punctata. Shell ovate, with strong longitu-
PL IX. f.15. dinal and transverse striz, co-
lumella two-plaited, outer lip
slightly denticulated, and the
ae somewhat compres-
sed.

p- 88. |

PI.IX.f17 large, spire very acute: the
four upper whorls are granu-
lated ; pillar-lip not reflected,
and having one fold; outer
lip very thin.
5. clandestina, Brocchi, p. 642. t. 14. f. 4.
6. Cypreola.. Brocchi, p. 321. t. 4. f. 10..
7. plicatula. Brocchi, p. 318. t. 4. f..7:
8. mitraeformis. Brocchi, p. 645. t. 14. f. 13;
9. rustica. Lister’s Conch. t. 824, f, 4.4,
t. 825. f. 45. and t. 827. £. 49.
—a and e Dillwyn’s Conch.
p: 533.
10. paupercula. Lister’s Conch. t. 819. t. 35.—
, Dillwyn’s Conch. p. 534.
11. turgidula. Brocchi, p. $19. t. 4 f. 4
12. Schrotereri. Encyc. Methed. t. 371. £ 2.—
f Dillwyn’s Conch. p. 539.
13. Barbadensis. Encyc. Method. t. 372. £.6.—.
Dillwyn’s Conch. p. 541.
14. sub-globosa.. Body almost globular & smooth;
Pl. X.f14. spe with three volutions,.
scarcely elevated above the
body; pillar-lp thickened and
thrown back on the body ;
with one fold; aperture oval ;
outer lip strong; inside denta-
ted and _ striated: Length
about an eighth and a half of
an inch.
There are varieties of this shell
differing in the Tength of the
spire.

_BUCCINUM:
1. prismatieum. Vid. p- 458
2. macula.

462

Maton and Racket in Linn.
Trans. VIII. p. 138. t. 4. f. 4.
—Dillwyn’s Conch. p. 638.

3. gibbosu- Dillwyn’s Conch. p. 605.—Lister’s

lum. Conch. t. 973. f. 28.
4. mmimum. Montagu, Test. Br. p. 247. t. 8.
f. 2.

2. macula.

STROMBUS.
1. tuberculatus. Dillwyn’s Conch. p. 675.—
Martini’s Conch. IV. p. 327.
t. 157. f. 1490.

MUREX.
1

_scaber. Brocchi, p. 448. t. 9. f. 17.
2, echinatus. Brocchi, p. 663. t. 8. f. 3.
3. nebula. | Montagu’s Test. Br. p. 267. t. 15.
f. 6.—Dillwyn’s Conch. p. 743.
4, Tritonis. Linné Syst. Nat. p. 1222.—Lis-

ter’s Conch. t. 959. f. 12.—
Dillwyn’s Conch. p. 727.

. Erinaceus. Donovan, Br. Sh. I. t. 35.—Dill-
wyn’s Conch. p. 690.

6. angulosus. Brocchi, p. 411. t. 7. f. 16.

4. gracilis. Donovan, Brit. Sh. t. 169. f. 2—

M. emarginatus.—Dillwyn’s

Conch. p. 742.

8. purpureus. Montagu, Test. Br. p. 260. t. 9.
£. 3.—Dillwyn’s Conch. p. 745.
Montagu, Test. Br. p. 261. t. 9.
f. 4.—Dillwyn’s Conch. p. 745.
muricatus. Montagu, Test. Br. p. 262. t. 9.
£, 2.—Dillwyn’s Conch. p. 746.

craticulatus. Broechi, p. 663. t. 14. f. 3.—

Dillwyn’s Conch. p. 740.
19. triangularis. Shell tapering, with nine whorls,
Pl. IX. £18. well defined, transversely stria-

ted; and the whorls crossed by
strong yarices, from the body
to the apex; three rows of them
are considerably higher than
the others, Shick gives the shell
a triangular form.

13. adversus. Adam’s Microscope, p. 638. t. 14.
f. 21.-Dillwyn’s Conch. p. 759.

14. granulatus. Rumphius, t.30. f L.—Dill-
wyn’s Conch. p. 756.

15. reticulatus. Gualtieri, t. 58. f. G.—Dillwyn’s
Conch. p. 758. ;

16. trunculus, Gualtieri, t. 31. C.—Dillwyn’s
Conch. p. 684.

Shell turrited, with five glossy
whorls, the upper volution
blunt at the apex, with longitu-
dinal ribs running from the

Cr

9. linearis.
10.
in

17. triplicatus.
Pl. IX. f. 19.

>

GEOLOGY OF THE

base to the tip of the spire;
columella with three plaits ;
beak short and slightly bent.

Shell turrited, strong, with six
whorls deeply divided by the
suture, with seven strongly
‘ warted longitudinal ribs; fine-
ly striated transversely; aper-
ture oblong, beak short ; inner
lip slightly reflected, with four
knobs ; outer lip with a row of
strong teeth within.

18. dentatus.
Pl. X. f.1.

TROCHUS.
1. Pharonius. Lister, t. 638. f. 26.—Dillwyn’s

Conch. p. 772.

Q. corallinus. Adanson’s Senegal, p.183. t. 12.
f. 4. —Dillwyn, p. 773.

3. Guineensis. Schroeter Bin, I. p. 712.—Dill-
wyn, p. 773.

4. Modulus. Lister, t. 653. f. 52.—Dillwyn,
p. 775.

5.tumidus. Montagu, p. 280. t.10. f. 4,.—
p- 777. Tro. Patholatus,

6. fasciatus. Schroeter, I. p. 747—Dillwyn,

. 783.

7. solaris. ee t. 622. f. 9.—Dillwyn,

p. 786.

8. crenulatus. Brocchi, p. 354. t. 4. f. 2.

9. miliaris. | Brocchi, p. 153. t. 4. f. 1.

0. tessalatus. Schroeter, I. p. 693.—Dillwyn,

. 794.

Dillwyn, p. 782.—Donovan, Br.
Sh. v. t. 155. f. 3.

‘Shell conical, umbilicated, with
five abrupt volutions ; body
large, in proportion to the
other whorls; a deep grove
runs spirally from the outer

__ lip to the apex, in the: centre
of the volutions ; above which
is a regular row of large tuber-
cles ; the whole shell is spiral-
ly striated ; and above the tu-
bercles there are regular spots
of a yellowish brown. Diam.
ths, length the same.

. cinereus.

12. torosus.
Pi KO.

TURBO.
1. acutus. Risso in Jour. des Mines, No.200.
Aout 1813. p. 6. Rissoa acuta.
Risso in Journal des Mines, p. 6.
Rissoa violacea.
Risso in Journal des Mines, p. 7.

Rissoa plicata.

2. violacea.

8. Rissoa.

4. costatus.

ENVIRONS OF NICE.——APPENDIX.

4, costatus. Dillwyn’s Conch. p. 860.—Wal-
ker’s Minute Shells, f. 4’7.
Maton and Racket im Linn. Trans.

viii. p. 180.-Montagu, p.362.

5. labiatus.

: t. 11. f. 6.
6. turgida. Shell turrited, with five volutions;
Pl. X. f. 3. very much inflated; separa-

‘ ted by a dee
strong longitudinal ribs ; and
very fine regular transverse
strie ; apex very sharp.

Shell pointed, with strong longi-
tudinal ribs and transverse
strie; inside ribbed; body
whorl, about equal to the
length of the spire. Length
13 aghth of an inch.

Shell pone strong, with five
longitudinal and transverse
strie ; inside ribbed; outer
lip thickened ; body longer
than the spire. Length 1}
eighth of an inch. —

Shell subulate, with ten glossy
well defined whorls, white,
aperture sub-rotund. _

Shell conic, im large and tur-

8. discrepans.
Pl. X. f. 4.

T Nh

9. glaber.
— ff 2;

10. minutus:

suture, with }

463.

ovate, pillar-lip smooth ; out-
er lip thin and crenated.
Length jth, breadth not quite
an eighth of an inch.

Maton and Racket in Linn. Tr.
p-177.—Montagu, Test. Br.
p- 300. t. 10. f. 7.

12. truncatus.

13. pullus. Dillwyn, Br. Sh. p. 822.—Do-
noyan, Br. Sh. I. t. 2. f. 2. to
13. cimex. Dillwyn, p- 821.—Da Costa’s Br.

Conch. p. 104. t. 8. £. 6.& 9.
Turbo cancellatus, Dorset.
Cat. p. 59. t. 14. £6. & 9.

14. phasianella. Risso in Journal des Mines,
No. 200. Aout, p. 6. Phasia-.
nella rubra.

15. geniculus. Brocchi, p. 659. t. 16. f. 1.

16. elegantissimus. Vid. p. 458.

17. striatus. Brocchi, p. 383. t. 6. f.'7.

18. Ulve. Dillwyn’s Conch. p. 840. Pen-
nant, Br. Zool. iv.. p. 182.
t.86. £120. Dorset Catal.

. 49. t. 18. f. 12.

19. interruptus. Dillwyn’s Conch. p, 841.—Mon-

ae Test. Br, p. 329. t. 20..
3

PLX. £13. gid;. spire short, with four | 20. parvus. —_ Dillwyn’s Conch. p. 85'7.—A-
‘) moderately rounded volutions3. by, dams in Linn. Trans. iii.
ees apex rather obtuse ; the whole ae m p. 66. t. 13. £.29. & 30. Tur-.
oy shell is covered with fine spi- | ‘- bo zreus, Donovan, Br. Sh..
ih ral striz, and clouded with| = t. 90. T. lacteus.
pale honey-yellow ; aperture | 21. cancellata. Brocchi, p. 377. t.'7. f. 8.
nearly round; pillar-lip slight- | 22. pusillus. Brocchi, p. 381. t. 6. f. 5.
ly reflected, and forms a sub- | 23. conoides. Brocchi, p. 660. t. 16. f. 2.
umbilicus ; outer lip thin. | 24. verrucosus. Shell with a ventricose body ;
ee Length about j,th of an PL.X. £12. spire with four very distinct
~ inch, breadth. about half its volutions ; the whole shell is
i-'% hy ength. ail ° covered with elevated knobs

_ the spire having only ‘four
_ volutions, and in the aperture
being rounder. P
Shell longitudinally ribbed ;
strongly striated transversely
between the ribs; body large
and spire short, with five well

defined “a aperture

11. breve.
PL X. f.10.—

in regular rows; the intersti-
ces deeply punctured ; aper-
ture ovate; outer lip strong ;
Lae slightly reflected to-
wards the base; inside ver
glossy. Length about 3th,
breadth somewhat less.

25. gracilis. Brocchi, p. 382. t. 6. £..6.
26. striatulus, Dillwyn’s Conch. p.85'7.—Mon-
tagu’s Test. Br. p. 306. t. 10.

£5.

There is also a variety of this
shell with strong, elevated,
longitudinal varices.

27. rugosus.

ci

464

27. rugosus. Dillwyn’s Conch. p.829.—Lis-
ter’s Conch. t.647. f. 41.—
Gualtieri, t. 65. f. F. & H.
Shell with strong longitudinal
and transverse striz ; the lon-
gitudinal striz terminate
Ww ere the outer lip joins the
ody, and give it the appear-
ance of fine papillae : the body
is large and ventricose ; spire
with five short whorls ab-
ruptly tapering to a sharp-
ened pats aperture ovate ;
outer lip thin and strongly
crenated; pillar-lipsmoothnear
the base, and slightly reflect-
ed, formmg a sub-umbilicus.
Length, an eighth and a half, '
breath 3th of an inch. —
Broechi, p. 981. t.6.£.4.

28. tigerina.
Pl. X. f.11.

ae
a

99. acinus.

HELIX. 4
1. vitrea. Dillwyn’s Con. p.919.—Chemnitz
383. t.15. £15.16.
2. polita. Dillwyn, p.881. Tur. polita, Linn.
Trans. viii. p.210. Donovan,
Br. Sh. t. 177. era
3. haliotoidea. ple ‘on!
ee 570. Bt
otoidea,
NERITA. — x

J. Glaucina. Dillwyn, p.978.—Donovan, Br.

Sh. I. t. 20. f. 1.—Gualtieri, |

t. 67. f. A. and B.
HALIOTIS. :
1. striata. Vid. p. 458. ¥
DENTALIUM.
1. Entalis. Vid. p. 458.

MADREPORA.

1. striata. Corals nearly straight ; divergent,
covered, with fine longitudinal
strize.

2, pistularia. Clavate, turbinate, base, with small
pustules, and undated ; hori-
zontally ridged; centre con-
cave; gills about 36, with in-
termediate ones, oval. ‘_

e

x if Triquetra. Linnzus, Syst. Nat. p. 1265.—

Ms zoornyrs

GEOLOGY OF THE ENVIRONS OF NICE.—APPENDIX.

PATELLA.
1. Virgmea. Dillwyn’sConch. p.1052.—Linn.
Trans. LV. p. 235.—Donovan,

_ Br. Sh. I. t. 21. f. 2.

. 2. Greca. Linnaeus, Syst. Nat. p. 1262.—

~ Dillwyn’s Conch. p. 1056.—Do-
novan, Br. Sh. I. t. 21. £.3.
Pat. reticulata.

3. pellucida. Linneus, Syst. Nat. p. 1260.—
Dillwyn’s Conch. p. 1042.—Do-
novan, Br. Sh. I. t. 31. f.1.

Linnzus, Syst. Nat. p. 1258.—
Dillwyn’s Conch. p. 1032.—Do-
novan, Br. Sh. I. t. 14

Linnzus, Syst. Nat. p. 1261.—

_ Dillwyn’s Conch. p. 1054.-Do-

~ novan, Br. Sh. I. t. 3. f. 2.

6. saccharina. Linnzeus, Syst. Nat. p. 1258.—

__ Dillwyn’s Conch. p. 1023.
illwyn’s Conch. p. 1015.—Lis-

_ ter’s Conch. t. 546. f. 38.

SERPULA. ~

4. vulgata.

5. fissura.

7. equestris.

Dillwyn’s Conch. p. 1073.—

3 Martini Conch, III. t. 24.
f. A.—Pulteney in Huch. Dor-
set, p. 53. t. 22. f. 5.

| 2 vermicularis. ba inn. Syst. Nat. p. 1267——

Iwyn’s Conch. p. 1083.—

Z ; Donovan's Br. Sh. ii. t. 95.
8. anguinia. Linnaeus, Syst. Nat. p.1266.—

' ~ Martini, 1. 1.2. £13. B, C—

Dillwyn’s Conch. p. 1080.
4. arenaria. Linneus, Syst. Nat. p. 1266.—
Martini, I. t. 8.19. A.—Dill-
; -__ _ wyn’s Conch, p. 1078.
5. lumbricalis. Linnzus, Syst. Nat. p. 1266,—

ai tin, It. 1.f 12 B—
Sbllleyns Conch. p. 1077.

ye tai,

‘ :

a
\... and a half eighths, breadth
three eighths of an inch.

There is a variety of this
with only 26 gills.
Turton’s tian iv. p. 630.——
Shaw, Nat. Miscell. t. 194.
Turton’s Linné, iv. p. 631.—Pal-
las El. Zooph. p. 313. No. 182.

3. ramea.

4. hirtella.

aR

a se

ow 1

PLATE Ix.

Engraved tor the Royal Soctely Tran VolVill. Page 464

=

Prawn by Capt= Drown Tograved Dy WED larare hanburgh

ats

x.

PLATE

Engraved by WD. Liaers Edinburgh

@ by Capt Hrown.

a

XXI. On certain Impressions of Cold transmitted from the Higher
Atmosphere, with the Description of an Instrument ad-
apted to measure them. By Joun Lesuiz, F.R.S.E.
and Professor of Mathematics in the University of Edin-
burgh.

(Read March 16. 1818. )

pnt distribution of Heat over the surface of our Globe, is a
capital object in the economy of Nature. The infusion of that
active element communicates to bodies the principle of mo-
tion, and quickens the ceaseless revolution of the circle of ge-
neration and decay. But Heat, unlike air, water, or earth,
appears never in a distinct and separate form: It exists only
in a state of combitation with other tangible substances ;
among which, it migrates from one to another. On the re-
gulated tide of this transmission, depends the stability of the
present order of things. A very small portion of the vast scale
of heat is requisite and salutary for vegetable or animal life.
A genial warmth fosters the powers of vegetation,—but push-
ed farther, it soon dries up the juices, and ‘shrivels the leaves
and tender shoots; on the other side, again, when reduced to
a low temperature, it benumbs the energy of production, and
finally stifles the expansion of life.

If the transfer of heat among bodies were much slower,
therefore, than what actually obtains, its inequalities would ac-
cumulate, and the greater part of this fair globe would be-

Von. VII. P. II, 3N come

466 ON IMPRESSIONS OF COLD

come a desert. The tropical countries. would be burnt up by
unmitigated fervour ; while eternal frost, usurping the polar re-
gions, would extend its dominion within the temperate zone.
The little portion of the surface left to animation, would be
blasted by the excessive inequalities of the seasons, and of the
diurnal vicissitudes. The sultriest days would have invariably
closed in nights of pinching cold, and this mild climate would
have exhibited all the rigours of a Canadian winter, succeeded
by the fervid heat of an oppressive summer.

The opposite condition leads to results still more appalling.
If heat encountered no impediment. in its internal motions,
but diffused itself with almost instantaneous effect, it might
amuse the fancy to contemplate for a moment the vast and
tremendous consequences. An uniform and unyarying tem-
perature would then pervade the globe ; no distinction of cli-
mate would exist, no vicissitude of seasons, and no grateful
alternation of day and night. The azure vault of heaven, per-
tually serene and cloudless, would lose all its animated charms.
If snow and hail would be unknown, so would likewise the re-
freshing influence of rain and dews. The face of the earth
would present a monotonous picture of sterility ; no verdure
to relieve the eye, —no vegetation,—and no sustenance for ani-
mals. All the springs of life would be locked up. The bene-
ficial effects,—the very existence, of artificial heat, would for
ever have been concealed; since the instant this was genera-
ted, it would spread and ingulf itself in the general mass.

It is, therefore, an important study, to discriminate the cir-
cumstances which modify and regulate the distribution of
heat among bodies. ‘Towards a correct knowledge of the
subject, very considerable advances have been made, though
some vague and crude notions are still suffered to prevail. To
comprehend rightly the observations and reasonings contained

in

:
Py
‘
Fs
‘S

‘io~=

oh

FROM THE HIGHER ATMOSPHERE. 467
in the paper now. submitted to the Society, it will be hence
expedient to take a retrospect of the facts which have been
disclosed relative to the communication of heat, In framing
this abstract, I shall abstain from all hypotheses, which might
assist, only to deceive, the imagination, but content myself with
stating the facts really ascertained, and with tracing out be
sarwelgpicgean to which they distinctly lead.

I have observed, that Heat never appears in a detached
form. Yet its materiality is evinced, by the expansion which
it invariably communicates to the substances with which it
unites. _ While it is attracted by any bodies, therefore, it must
introduce into them some repulsive force, which had previously
existed among its own particles.. Heat must hence be a fluid
of extreme tenuity, yet endued with an_ irresistible elastic
force. . But when a substance, either from a chemical or. me-
chanical impression, suffers a sudden change of constitution,
and makes a copious discharge of heat, this emission is al-
ways accompanied by an effulgent light. On the other hand,
when the rays of the sun, or even those of a bright lamp,
are intercepted by any body, and seem lost or extinguished,
a corresponding increase of warmth is immediately betrayed
at the absorbing surface. It follows from this and similar
facts, that heat is the same fluid as light, only in a state of rest
and combination. In short, heat is latent, invisible, light,—
the agelov gus of the ancients,—which has been arrested in its
rapid flight, and cannot again be liberated, without such a

. violent change of condition, as will leave entire the repulsion

of its own particles, to create the requisite projectile force.
In ordinary cases, however, the light remains imprisoned in
the substance with which it combines, and only migrates from
one portion to another. ; aie

3N 2 The

468 ON IMPRESSIONS OF COLD

The progress of heat through different bodies, depends
on their peculiar constitution, and varies extremely in its rate.
To examine this phenomenon more closely, it will be proper
to distinguish the conducting media into the three classes of
—solid—liquid—and gaseous.

J. In the case of a solid conductor, if one end of a rod be
heated, the effect will gradually advance, yet not with a con-
tinuous flow, to the other end. If the rod were conceived to
be distinguished into elementary spaces, each of these in the
progress of communication must experience, within imper-
ceptible limits, an alternate accession and reduction of heat,
and must consequently first expand and then contract. In
fact, it absolutely could not receive and deliver heat at the
same instant of time, for a contemporaneous expansion and
contraction—the necessary result—would imply an absurdity.
But contraction naturally succeeds to expansion, as a part of
the same vibratory impression. Those elementary conducting
spaces, must therefore undergo an alternating hot and cold
fit ; so that the communication of heat through a solid sub-
stance, is performed by a series of minute articulate motions,
resembling the progressive vermicular action by which the
creeping insects are enabled to advance along the ground.
The celerity of the transfer of heat through any solid is hence
determined by the extent of such articulations, and the rapid
succession of the internal oscillations ; which again depends on
the elasticity of the conducting substance, modified by the
influence of its density.

2. In the communication of Heat through liquids, an auxili-
ary principle, originating in the internal mobility of the me-
dium, concurs to accelerate its progress. The warmed portions
of the fluid, acquiring expansion, rise upwards by their conse-

quent

FROM THE HIGHER ATMOSPHERE. 469

quent buoyancy, and spread over the surface. Ina short while,
therefore, the heat is distributed through the whole liquid mass,
in successive strata, from the bottom to the top. But liquids
also conduct heat by a slow process in every direction, like
solids. This protracted diffusion of influence, which is’ exert-
ed in restoring the equality of temperature through the body
of the liquid, succeeds to the operation of the principle of
buoyancy. While the surface becomes again colder, the bottom
grows gradually warmer ; the heat working downwards, by a
continual transfer, from stratum to stratum, of the stagnant
Flak sit v"

' The diffusion of heat, then, depends chiefly on the expan-
sion and internal mobility of the liquid medium. Thus, alco-
hol rapidly diffuses heat, while the viscid oils, especially at low
temperatures, clog its motions. The circulation is in general
quicker when the liquid is very warm, its expansibility, and’ its
aptitude for internal: migrations being now increased. In-ap-
proaching the boiling point, water expands largely by equal’ac-
‘cessions of heat ; but near congelation, its-expansions or contrac-
tions are extremely small. The conducting power of water at
a very low temperature, is hence nearly the same as if it were
a solid, or remained motionless; the Same, in short, as if by
the addition of isinglass, it were changed into a thin jelly.
Such are the conducting powers which a liquid substance
combines when at rest, or left merely to the play of its internal
motions. But if made to flow in a stream, it will evidently, in
consequence of the frequent renewal of contact, abstract heat
more quickly from every warm solid body which is immersed in it.
Thus, I find, that, in ordinary circumstances, water, advancing
at the slow rate of a mile in three hours, will yet conduct away
heat twice as fast as when quite stagnant. Consequently a cur-

rent

470 ON IMPRESSIONS OF COLD

rent of three miles an hour would accelerate tenfold the trans-
fer of heat.

It isof essential importance, however, to remark, that in all
cases where the medium of communication is a liquid, the na-
ture of the hot surface, whether vitreous or metallic, rough or
polished, has no influence whatever m modifying the rate
with which the heat is drawn off and dispersed. Thus,
a hollow tin ball filled with hot water, will lose its heat just
as fast when immersed naked in cold water, as if it were cover-
ed with linen, or paper, or a coat of any sort of pigment.

3. Heat is transferred through a gaseous medium by a more
complex process. It is partly conducted, as in the case of li-
quids, by successive communication through the stagnant mass,
joined to the more copious effect of the buoyant streaming of
the heated portions of the fluid. But another auxiliary prin-
ciple, depending merely on the nature of the heated surface,
now comes into action. Let two equal hollow balls of bright
thin silver, the one naked, and the other covered with a fold of
cambric or paper applied closely to its surface, be filled with
warm water, and sitspended in a close room. The former
will be found to lose ii: parts of heat, in the same time that
the latter sheds 20 parts. Of the heat thus spent, 10 parts,
from each of the balls, are communicated in the ordinary
way, by the slow recession of the particles of air, as they
come to be successively heated by their proximity. The re-
maining portions of heat, consisting of 1 part from the bright
metallic surface, and 10 parts from the cambric, are pro-
pagated through the aérial medium, by some peculiar pro-
cess. In like manner, two equal hollow balls of glass, the one
gilt with gold or silver leaf, being filled with warm water, and
suspended in a room, the naked one will discharge 13 parts
of heat, while the gilt one will lose only 7 parts; 6 parts be-
ing spent by each, in the same way as if they had been im-

mersed

a SS”

ee =

FROM THE HIGHER ATMOSPHERE. 471

mersed jin a cold liquid, while the vitreous surface projects 7
parts, and the metallic surface only 1 part. The same dif-
ferences depending on the nature of the superficial boundary,
are observed to take place in the heating as well. as in the
cooling of bodies. Thus, if the silver balls be filled with wa-
ter colder than the:temperature of the room, they will acquire
heat in the same proportions as they before lost it. The na-
ked' ball will gain only 11 parts of heat, while the coated will
receive: 20. parts , ; 9 10

But the air is still an: essential vehicle:of didi various im-
pressions of heat or cold. An absolute: vacuum is unattain-
able'in Nature ; but the dispersive effects are always diminish-
ed, though slowly, by rarefyimg the medium. Thus, when the:
air is rarefied about 200 times, the abductive power from the
glass balls will be reduced from 6 to 14; while the peculiar
discharge of heat at the naked surface is lalepititindd from 7 to 5,
and that at the gilt surface from 1 to 2; the: naked ball now
i 62 parts of heat, and’ the gilt one only 23.

> ns

ocThe: offsite ‘are baliemisatiad a differ ent gaseous. mmadium, Thus;
dae same balls, with a vitreous and a metallic surface; would
discharge 31 and 25 parts of heat, if immersed in hydrogen:
gas ; both of them now losing. 24 parts by the powerful abduc-
tion of this gas. But: if the medium be rarefied. about 200:
times, the’ quantities of heat emitted, from the naked. and the:
gilt ball will be hae ane to 13 and 83..

As igesfinedoe oe ate or, still ‘ines one of ‘inert paper, or
vegetable pigment, projects. heat the most ‘copiously ; so those-
surfaces likewise intercept the impressions most effectually.

But a bright metallic surface detains only the tenth part of these-

impressions, and reflects all the rest. Hence the power of a me-
tallic speculum, contrasted with that of a glass mirror, in con-
centrating °

472 ON IMPRESSIONS OF COLD

centrating the heat or cold projected from any remote body.
Hence also the construction of the Pyroscope, a delicate instru-
ment, adapted to distinguish and measure those peculiar impres-
sions of heat or cold. It-consists of a differential thermometer,
having one ball naked, and the other coated with gold or silver
leaf; this metallic surface reflecting the greatest part-of the
projections, while the vitreous surface absorbs almost the whole
effect. Ifa broad plate of glass be interposed before a cubical
canister holding hot or cold water, the action on the pyroscope,
though concentrated by a reflector, will yet'be very much redu-
ced. But, on removing the plate farther from the canister, and
therefore nearer to the reflector, this action will be still more
diminished ; so as at last to become.almost extinguished. Hence
the projected influence of heat or cold consists not in any
streaming matter, for the same proportion of the warm or fri-
gid rays would evidently be intercepted by the glass screen in
whatever part .af the route between the canister and the re-
flector it was planted.

But the question is completely decided, by varying the ex-
periment. Let two glass plates be covered, each on one
side with tin-foil ; applying the metallic surfaces now together,
place the double sereen immediately before the hot canister,
and the effect on the pyroscope will be greatly reduced ; re-
verse the position of the plates, by exposing the coated sides,
and the action on the sentient ball will be entirely extinguish-
ed. The interposition of a screen would in every case detain
the whole impressions, if it did not itself become affected by |
them, and therefore come to act as a secondary but feeble pro-
jecting surface. Hence the different influence of a metallic
screen, in comparison with one of glass or paper.

The impressions of heat or cold emitted from a body are
not sent equally in all directions. Those projected perpendi-

cular

FROM THE HIGHER ATMOSPHERE. 473

cular to the surface of a cubical canister containing either warm
or iced water, are the most intense, and the rest appear to di-
minish in the ratio of the sine of obliquity. Hence the action
exerted on the sentient ball of the pyroscope, is always pro-
portional to the visual angle subtended by the propellent sur-
face.

Nor are those i impressions necessarily propagated in straight
lines. If connected rings of pasteboard be fashioned into a
sort of cornucopia, its mouth being directed towards the fire,
notwithstanding the twisted form of the passage, a very consi-
derable action will be indicated on the ball of the pyroscope,
presented at the narrow end.

From all these combined observations it follows, that the
portion of heat or cold, of which the discharge depends on the
quality of the surface, is propagated by the vehicle of its gaseous
medium, though not by any actual streaming of fluid matter.
No alternative then remains, but to admit that the impressions
of heat or cold are conveyed through the air with a spreading
and progressive tendency, in the same, manner as the pulses of
sound. The aerial medium, by a series of internal oscillations,
successively transfers its charge, and delivers an impression at
the end of the chain of communication, of the same kind pre-
cisely as it had received at the beginning.

This rapid transmission of Heat to a distance from its source,
has been hastily termed radiant, and various inaccurate concep-
tions are entertained concerning its mode and extent of action.
1. In the first place, then, the process now described never ob-
tains, unless where a difference of temperature occurs ; and
it only contributes, along with other active causes, to restore
the equilibrium of heat. 2. But, in the next place, it has in
every case a subordinate share only in the diffusion of heat.
When the air is perfectly still, and of the ordinary density, the
tide of heat vibrated from a vitreous surface amounts scarcely

Vou. VIII. P. II. 30 to

474 ON IMPRESSIONS OF COLD

to half of the whole discharge, and from a surface of polished
silver, it exceeds not the twentieth part of the entire expendi-_
ture. But such are the accelerating effects of a current. of air,
that, in a high wind, the pulsations of heat darted from a vitre-
ous and a metallic surface may not form the twentieth and the
two hundredth part. In a medium of hydrogen gas, those
pulsations are comparatively feebler, reaching, in the case of a
stagnant atmosphere, only to the eighth or the eightieth part of
the full discharge, with a proportional diminution when the af-
fected surlace is exposed to the action of a current.

The influence of the pulsatory: emission of heat or cold, has,
therefore been greatly exaggerated. It comes merely as an auxi-
liary to the other modes of restoring the equilibrium of the ig-
neous fluid, and it often contributes a very small share only to-
wards the general effect. But whenever a body, left to itself
in the atmosphere, is observed to change its temperature,
some pulsatory action may be presumed to combine with the

OY he eS Mm —

operation.

It is easy, in any case, to ascertain the real direction of the
aérial pulses. Whether a substance acquires or loses heat, it al-
ways approaches to the temperature of the ambient medium
by the very same process. The hot or cold pulses are pro-
jected from this approximating surface with an expansive sweep.
‘On the contrary, when a body maintains either a higher or a
jower temperature than that of the surrounding atmosphere,
like the sentient ball of the pyroscope in the focus of a re-
Hector fronting a charged canister, it receives and absorbs the
impressions vibrated at a distance. ‘the intervention of a pa-
per screen does not prevent the spontaneous emission of hot
or cold pulses, but will effectually obstruct their passage from
a remote object. .

Some theorists have imagined, that the escape of heat re-

? ; . np ees vil
quires free space or vacuity. But a body will either.lose
gain

lt rte os

cag

FROM THE HIGHER ATMOSPHERE. 475

gain heat with the same facility, in a small closet, as in a spa-
cious room. Let a glass ball of 3 inches in diameter, and
filled with hot water, or a frigorific mixture, be suspended in
the centre of a balloon of 18 inches in diameter, and it
will be found to change its temperature almost at the same rate
as in a close apartment. If the balloon were much smaller,
however, the effect would become sensibly diminished, because
the whole of the included air, being rendered somewhat hot-
ter or colder than before, would excite a feebler action at the
surface of the ball. A similar modification would take place if
the ball were formed of hollow silver. Yet this large shell of
glass evidently forms a complete screen, which will absorb all

the impressions emitted within it.

The sun is the great fountain of that heat which vivifies our
planet. Of the solar beams, part are detained in their passage
‘through the atmosphere, and the rest are absorbed at the sur-
face of the earth. From experiments with the photometer, it
follows, that, even when the sky is most serene, only one-half
of the sun’s light, sloping at an angle of 25°, will reach the
ground ; and that, at an angle. of 15°, the proportion is redu-
‘ced to one-third ; but with an obliquity | of 5°, only the twen-
tieth part of the whole can gain the surface. The effect of this
absorption during the day, is to raise the temperature of the
external crust of the globe. Very few of the incident rays are
again reflected from the surface. An expanse of sand, or even
of chalk, however offensive by its white glare, yet scarcely
sends back a fifth part of the light into the mass of air. A green
sward, or a dark soil, absorbs almost the whole of the lumi-
nous particles.

Of the heat thus accumulating at the earth’s surface, a imal
portion penetrates into the soil, but the greatest share is dispersed
by communication to the ambient air. In the progress of the

302 } day,

4716 ON IMPRESSIONS OF COLD

day, therefore, the ground always becomes warmer than the
incumbent stratum of atmosphere. This: effect is greatest
in the tropical countries, where the sun gains a higher altitude,
and pours his light in a full stream. Winds very mate-
rially check the accumulation of heat at the surface, and the
calorific action is besides diminished in cloudy weather. A
ploughed field is more affected by the sun’s rays than a
grassy plot, since a loose or spongy superstratum, by exposing
multiplied surfaces, dissipates more quickly the impressions of
heat communicated to it.

The best mode of examining the difference between the tem-
perature of the surface and that of the incumbent air, is by means.
of a pendant differential thermometer, from one to three feet
in length. It consists of a ball and long stem, to which ano-
- ther similar ball, with a short portion of tube, having its bore
swelled into a narrow cylindrical reservoir, is hermetically join-
ed. The reservoir exceeding not the tenth of an inch in dia-
meter, detains and supports the tinged sulphuric acid by its
capillary attraction, (see fig. 5. Pl. XL) This instrument be-
ing suspended in a vertical position, the lower ball approach-
ing or resting on the ground, while the upper ball, at a
moderate” elevation S, is enci ‘cled by the incumbent stratum
of air, the rise of the coloured liquor in the stem will mark
the excess of warmth below, and indicate very minute dif
ferences of temperature. Last summer I made some ob
servations of that sort, but not so extensive as I have since
projected. The effects were found to be extremely various.
In sun-shine, and calm, weather, the ground was sometimes
thirty millesimal degrees warmer than the air only a few
inches above it *. But when the sky happened to be much
overclouded, or when strong winds swept over the surface,

the

eo SN aa ee ee ee eS

* It may be proper to repeat, that, in all the combinations of the differential
thermometer, the divisions of the scale are made to correspond with the thousand
parts of the interval between freezing and boiling water.

oe

PLATE XI.

i Secreyy Tran. Vol VT Page 476
]

Eng hy WED Liars Bane

FROM THE HIGHER ATMOSPHERE. 477

the accumulation of heat would sometimes hardly reach to
three degrees. Under like cireumstances, but especially
when the air was still, the differential thermometer indicated
more than twice as much effect on fresh ploughed land as
on fine pasture. Nor was this inferiority of a surface of turf
owing to the waste of heat produced by a more copious exha-
lation of moisture; for, on spreading a layer of dry hay, or
even wool, over a part of the naked soil, the temperature of it
was in a: few minutes reduced to the same degree as that of the.
grassy sod..

The influence of reflex light, from the clouds and the sky, in
heating the ground, is often very considerable. The rays sent
from a fleecy canopy may sometimes amount to the half or the
third part of those which would be received directly from the sun..
But a stratum of dense black clouds intercepts almost the whole
of the scattered light. A similar effect: is produced by another.
sort of screen. Thus, when. the sky. was overcast, but the wea-
ther calm, the: pendant differential thermometer intimated
scarcely two degrees of heat at the surface, in a small fir wood;
but marked eight or ten degrees, when carried to a neighbour-
ing glade. )

In this climate, about two hours after sunrise, the-ground kas
the same temperature as the incumbent mass of air, but grows
commonly warmer than it, till nearly two-hours after. noontide;
from which time, it again declines, and becomes relativel y cold-
er than the air, perhaps two hours: before sunset ; sinking still
Jower during the night. The differences are thus comparative-
ly very small between the temperature of the ground and that
of the conterminous air, seldom exceeding the fifth, or perhaps
even the tenth part of the whole diurnal change. The hot or
cold pulses discharged from the ground, must, therefore, in all
cases, be only trifling, and quite insufficient to produce that rapid
approximation to an equilibrium which is actually observed. I

was

478 ON IMPRESSIONS OF COLD

was hence still inclined to think, that the statement which I had’
formerly made, of the existence of an ascending warm current
in the atmosphere, combined with a descending cold current,
was adequate to the explication of all the phenomena. It is:
obvious, indeed, that the lower portions of air, becoming heat-
ed, in the progress of the day, by their contact with the ground,
must rise upwards, and their place will consequently be sup-
plied, by like portions of cold air which descend from the high-
er regions. These opposite currents, though set in motion du-
ring the flood of light, will continue their play long afterwards,
perhaps through the greater part of the night, till again vigo-
rously excited by the presence of the sun. Hence the ground
is only heated to a certain limit during the day, and grows al-
ways colder as the night advances.

But my late ingenious and learned friend Dr Wexts, by the.
publication of his Essay on Dew, which contains some acute ob-
servations, conjoined with a few striking experiments, though
performed in the gross way, had contributed to revive the no-
tion of a copious radiation, or pulsatory discharge of heat from
the earth’s surface. It was, therefore, desirable to ascertain
the existence and real extent of such pulsations. The accu-
rate means of determination were within my reach, though I
had hitherto, in a great measure, neglected their application ;
for though the pyroscope measures those impressions with
great delicacy in a close apartment, it is liable out of doors to
some derangement from the influence of light, and has its ac-
tion diminished by the sweep of violent winds. To avoid as
much as possible these disturbing influences, I constructed
a small pendant pyroscope, the lower ball being left naked,
and the upper ball gilt with silver-leaf, to reflect almost the
whole of the incident light. This instrument I fixed to a short
arm, made to slide along a staff which could be stuck in the
ground, In the month of August last, I carried it, with some

other

FROM THE HIGHER ATMOSPHERE, 479

other apparatus, into the country, for the greater convenience
of making observations. This pyroscope being let down with-
in a few inches of the ground, generally indicated an impres-
sion of heat during the day, seldom exceeding, however, three
er four millesimal degrees. But I remarked, with surprise, in
more than one instance, that towards evening, when the sky be-
came clearer, the liquor would fall a degree or two. Yet the
ground was still warmer than the air, and ought consequently to
have augmented, rather than diminished, the calorific pulsa-
tion. \ I now began to suspect that an opposite impression was
somehow showered from the atmosphere, and therefore set about
examining the subject closely ; though a tract of cloudy and boi-
sterous weather greatly retarded my inquiries. I fitted, a little
below the sentient ball of an ordinary pyroscope, a small circu-
lar: plate of tin, hammered into aslight concavity. The instru-
ment, having its action thus more than doubled, put the main
fact beyond.all doubt.

The object now was to discover, if those cold pulses shot
downwards from an azure sky, were subject to variation, and
whether they prevailed during the day, as well as at night.
I had a segment of a sphere hammered ont of tin, about nine
inches wide, and three inches deep, with a vertical arch, to
which the pendant pyroscope was attached, the sentient ball
being placed in the middle between the centre and the
bottom. But the indications were not altogether satisfactory,
owing partly to the influence of strong light, though chiefly
to the disturbing effects of the violent winds which happened
then to prevail. I therefore resumed the erect pyroscope, and
augmented its action, by adapting under the sentient ball an
eee pnerieal tin-cup of about 2 inches in diameter. To screen
the instrument from the sun and the wind, I placed it in the
middle of a wide earthen pitcher set behind a north wall. The

weather

480 ON IMPRESSIONS OF COLD

weather being very unsteady, I had to watch the intervals of an
opening sky. Covering the mouth of the pitcher with a pane
of glass, the pyroscope would sometimes indicate one or two
degrees of heat ; but, on removing that screen, it always mark-
ed impressions of cold amounting perhaps to five or six de-
grees, as often as the clouds parted, and left a blue space near
the zenith. The continual darting, by day and night, of cold pul-
sations from the sky was thus ascertained; and nothing seemed

wanting but to improve the construction of the instrument, and ~

render it commodious and portable. I resolved to inclose both
balls within the same cavity ; the lateral ball being gilt, and of
the same colour as that of the annexed reflector;.and the naked
sentient ball being placed in the focus. By this disposition,
the influence of light was almost completely destroyed, its ac-
tion being made equal on both the balls. But, to protect those
balls from the disturbing effect of wind, it was requisite, that
the cup containing them should be deep and rather nar-
row. If the cold pulses to be measured were darted only in a
vertical direction, the parabolic conoid would certainly be the
proper form of the reflector. I was convinced, however, from
some imperfect trials, that such impressions were likewise sent
down at different angles of obliquity. Supposing their inten-
sity to be equal in all directions, an hemispherical reflector would
answer best. But the focus, instead of a single point, would then
have branched into the diverging arcs of the caustic curve, and
the sentient ball of the pyroscope would have required half the
dimension of the reflector itself, (see fig. 11. P]. XI.) The main
cbject, however, was to measure the impressions received from
the upper portion of the atmosphere, that part near the horizon
being generally obstructed by clouds or vapour. I therefore a-
dopted an intermediate plan, and selected for the reflector a trun-
cated oblong spheroid, cut through the upper focus by a plane per-

pendicular

4

FROM THE HIGHER ATMOSPHERE. 481

pendicular to the axis, and having the sentient ball of the py-
roscope placed in the lower focus, (see fig. 2, 3. and 4.) It is
evident that the impressions which pass through the first focus
in every direction, must be reflected towards the second focus.
But since the upper focus occupies the middle of the aperture,
all the cold pulses which enter the spheroid will be nearly col-
lected on the sentient ball of the pyroscope. The more oblique
impressions, however, striking the sides of the reflector at a
greater angle of incidence, will be less copiously reflected ; and
consequently this compound instrument will indicate more fully
the action of that quarter of the heavens to which it is turned.

Of these truncated spheroids, I had two made of planished
tin; the one being eight inches high, with an extreme width
of the same, and its focus two inches from the bottom; and
another nine inches high, and six inches broad.; the focus be-
ing only an inch from the bottom. I had one or two more
reflectors, constructed of plated copper, after the same forms,
but with only half those dimensions. The more eccentric
spheroid being mounted on pivots, was better fitted to. explore
any particular portion of the sky, (see fig. 2. Pl. XI); To this
inquiry my attention. was now drawn. Watching when the sky
appeared most serene, I directed the instrument, first to the
zenith, and then. successively declined it, till it came within.
twenty degrees of the horizon. But the instrument continued
to indicate the: same frigorific impression, or about forty or
fifty millesimal degrees: at all inclinations. It was, therefore;
ascertained, that the action of a given section or angular por-
tion of the sky, is the same at every obliquity..

With the erect spheroid, I found, in cloudy weather, that the:
frigorific impression diminished, in proportion as the humid
mass, floating in the atmosphere, seemed to descend. When
the sky was canopied with high fleecy clouds, the effect on the

Vor. VIII. P.IL 9 instrument

482 ‘ON IMPRESSIONS OF COLD

instrument might amount to twenty degrees ; but when the
congregated vapours sunk so low as to hover on the hilly tracts,
the impression would frequently not exceed five degrees. It
was evident, therefore, that the effect depends on the altitude
of the lowest range of clouds, and might seem to result wholly
from the difference of temperature which prevails there, com-
pared with that of the surface.

But the same conclusion was drawn from another set of ob-
servations. In a calm day, when a mass of dark clouds was
spread at no great elevation above the surface of the ground,
the spheroid indicated only five millesimal degrees in a verti-
cal position, and yet marked still the same quantity, when de-
pressed to an angle of thirty degrees above the horizon. But
had this impression of five degrees penetrated directly through
the clouds, from the higher regions of the atmosphere, scarce-
ly one-half of a degree could have escaped through the mass
of vapours by the oblique passage. A range of clouds hence
acts as a complete screen, absorbing and extinguishing all the
hot or cold pulses received on it.

Since clouds consist merely of dispersed aqueous globules,
their influence, I conceive, may be safely inferred from that of
water itself. I therefore inclosed an inverted pyroscope in a
spheroidal cup, and suspended it a few feet above the ground,
while the sky appeared clear and blue, (see fig. 7. Pl. XL.) ;
then passing a silver tray under it, the reflected impression of
cold amounted to twenty-five degrees: on interposing a plate
of glass, this was reduced to two degrees ; but on removing
it, and pouring a sheet of water over the silver, the effect was
absolutely extinguished.

Most of these observations and experiments were made du-
ring the months of September and October 1817 on the top of
the Tower at Raith,—a spot very favourable for such researches,

and

FROM THE HIGHER ATMOSPHERE. 483

and endeared to me by many pleasing associations. The re-
sult of them has been the construction of a delicate instrument,
which will be deemed, I hope, a valuable accession to meteo-
rology, and indeed to physical science in general. From the
term «aiéeioc, which, in reference to the atmosphere, signi-
fies at once clear, dry and cold, I have appropriated the
name of ithrioscope to this new combination of the py-
roscope. The sensibility of the mstrument is very striking,
for the liquor incessantly falls and rises in the stem with
every passing cloud. Under a fine blue sky, it will some-
times indicate a cold of 50 millesimal degrees; yet on other
days, when the air seems equally bright, the effect is only 30°.
The causes of these variations are not quite ascertained. The
action is in general greatest under a clear and translucid at-
mosphere. But particular winds, blowing at different altitudes,
seem to modify the effect, and so may perhaps the transition.
from summer to winter.

There are three principal forms of the Athrioscope: 1. Erect:
2. Sectoral ; 3. Pendant.

1. Erect.—All the requisite conditions for measuring the at-
mospheric impressions are attained, by adapting the pyroscope
to the cavity of apolished metallic cup, of rather an oblong
spheroidal shape, the axis having a vertical position, the lower
focus being occupied by the sentient ball, while the section of a
horizontal plane; at the upper focus, forms the orifice, (see
fig. 3. Pl. XL.) The cup may be made of thin brass. or sil-.
Very. either hammered or cast, and then; turned and polish-.
ed on a lathe; the diameter being from two. to four inches, and’
the eccentricity of the elliptical figure varied. within. certain li-
mits.according to circumstances. The most convenient propor-
tion, however, is, that the eccentricity should be equal to half.
the transverse axis, or that the focus should be placed at the

3P2 third’

484 ON IMPRESSIONS OF COLD

third part of the whole height of the cavity, the diameter of the
sentient ball having likewise nearly the third part of the diame-
ter of the orifice of the cup. In order to separate the balls of
the pyroscope, the gilt one may be carried somewhat higher
than the other, and lodged in the swell of the cavity, its stem
being bent to the curve, and the neck partially widened, to
prevent the risk of dividing the coloured liquor in carriage.
The instrument. is adjusted to its position by a clasp which
slides along the stalk. A lid of the same thin polished me-
tal as the cup itself, is fitted to the mouth of the ethrioscope,
and removed only when an observation is to be made. The
scale may extend to 60 or 70 millesimal degrees above the
zero, and about 15 degrees below it.

2. Sectoral.—To ascertain and measure the cold pulses shot
obliquely, as well as those in the vertical direction, the zethrio-
scope may be constructed to turn towards any portion of the
sky, (see fig. 1. and 2. Pl. XI.) To effect this, the form best fitted
for reflexion would be that of an hyperbola, whose asymptotes
have an inclination equal to the visual angle of the space to be
explored. Fig. 1. may give an idea of the construction. But
to obtain accurate results, the focal ball must be small, and the
hyperbolic conoid wide and much extended. It will answer
nearly the same purpose, however, to adopt a truncated sphe-
roid, of great eccentricity. Let the height of the focus, for in-
stance, be one inch, that of the entire cavity nine inches, and,
consequently, the widest diameter six inches. The shape re-
presented in fig. 2. is rather more distended, its extreme
width being equal to double the eccentricity, and the focal ball
dividing the height of the orifice in the ratio of 1 to 3+ 8,or
of 6 to 35 nearly. The pyroscope inserted has a peculiar twist-
ed form, and receives its adjustment from a moveable socket.
While the sentient ball remains always in the same position,

the

FROM THE HIGHER ATMOSPHERE. 485

the axis of the instrument can, by means of a screw acting on
the limb of a quadrant, be depressed or elevated to any given
angle. But the effect will chiefly be produced by the direct
impressions: for the lateral pulses, striking less obliquely
against the cavity of the spheroid, will be feebly reflected.

This moveable axthrioscope was placed in a convenient si-
tuation out of doors, when the sky appeared free from clouds,
and had assumed a clear blue tint. The spheroid being turn-
ed first upright, the effect was noted ; but this continued still
unchanged, on depressing the axis successively, till it had ap-
proached the limit of energetic range, or within 20 degrees of
the horizon.

From every portion of the sky that subtends a given visual
angle, there is hence received the same quantity of the frigorific
pulses. But such would likewise be the result, if they were
showered from the horizontal surfaces of the successive strata
which divide the atmosphere ; since, although the intensity di-
minishes in the ratio of the sine of obliquity, a propellent space
broader in proportion is, for each elemental angle, brought
into action, as appears from the inspection of Fig. 10. Let
BC represent the boundary from which hot or cold pulses
are darted: A being the point at which these are recei-
ved, let BS and Ce denote minute portions of the vibrating
surface. A perpendicular Ck to AC would send impres-
sions in the direction CA, equal to those emitted by Ce. But
that the effects produced at A, from the projections of Ck and
Bd should be equal, the distances CA and BA must be pro-
portional to those breadths ; wherefore the triangles CA & and
BA 6 are similar to the elemental angles CA c and BA d equal.
It hence follows, that the impressions sent from a cluster of
such angles, amounting perhaps to ten or fifteen degrees, near
the vertical position, are equal to those contained within the.
same aggregate angle in an oblique direction. This entire

agreement :

486 ON IMPRESSIONS OF COLD

agreement between theory and observation is most satisfac-
tory.

3. Pendant.—The zthrioscope might be reduced to a small-
er and more compact form, by conjoining with it a pendant
differential thermometer. Neither of the glass balls in this
case requires to be gilt. But of the Pendant A‘thrioscopes
there are two varieties. In the first, the balls of the pyroscope
are enclosed by hemispherical brass cups. (See Fig. 6. Plate
XI.) These, however, may be a little deeper, forming seg-
ments about 10 or 15 degrees more than the hemisphere.
The pyroscopic balls, with two-fifths. of the diameter of the
cups, should be placed in the middle, between the centre and
the bottom. In the second variety, the lower ball of the pyro-
scope is encased by a hollow sphere of brass, composed of two
pieces which screw together, and the upper ball occupies the
focus of the cup, which needs scarcely be more than two inches
wide. (See Fig. 4.) This variety of the instrument is more
portable than any of the rest, and equally accurate; but owing
to the brass casing, it is, under a change of temperature, rather
slower in its action. The construction is rendered still more
commodious, by having the stem of the differential thermome-
ter inserted through a projecting circular piece, somewhat lar-
ger than the upper ball, which screws into a perforation at the
bottom of the cup, and then forms part of the same reflecting
cavity. This arrangement allows not only the standard of the
:nstrument to be occasionally detached, but also the cup itself,
_-a circumstance at once conducive to the safety of carriage,
and to the preservation of the metallic lustre and polish,

On replacing the metallic lid, the effect is entirely extin-
guished, and the fluid in the stem of the differential thermo-
meter immediately sinks to zero. A cover of pasteboard has
at first precisely the same influence ; but after it has itself be-

come chilled by this exposure, it produces a small secondary ac-
tion

FROM THE HIGHER ATMOSPHERE. 487

tion on the sentient ball, scarcely exceeding, however, the tenth
part of the entire and original impression. A lid of glass or of
mica intercepts the impressions like one of paper ; for the admis-
sion of light has no deranging effect, ifthe athrioscope be rightly
constructed and highly polished. The minute secondary ac-
tion is almost ‘extinguished, if screens of paper, glass, or mica,
be held at some distance above the mouth of the instrument.

The variety composed of two hemispherical cups will answer,
as an inverted zthrioscope, for measuring, at some elevation,
the warm pulses sent up from the lower strata. It is only re-
quisite to cover the upper hemisphere during the observation
with its metallic lid. ‘The same form of the instrument might
likewise conveniently be employed, when its altitude is not
very considerable, to determine the difference of the tempera-
ture of the surface of the earth, or of the sea, from that of the
superincumbent stratum of air. This difference, it would ap-
pear, from some unfinished observations which I have made,
is expressed, on Fahrenheit’s scale, by two-thirds of the millesi-
mal degrees indicated by the compound pyroscope. Nor is
this effect sensibly altered by the proximity of the terminating
surface, because its indefinite expansion will always present
nearly the same visual angle. Hence the relative temperature
of the surface of the sea, may be easily discovered from an
eethrioscopical observation performed at the stern or the prow
of a ship while under full sail.

In the Pendant Atthrioscopes, both the glass balls are left
naked ; but, in the Erect and Sectoral kinds, the lateral ball is
always gilt. This condition, however, is not essential, since the
concentration at the focus would be sufficient, by its excess alone,
to produce an adequate effect. Hence the observations may
be varied, by introducing within the reflector a differential
thermometer, either consisting of translucid balls, or composed
of balls blown from black glass. When the latter kind is used,

the

488 ON IMPRESSIONS OF COLD

the liquor will indicate merely the difference of opposite ef-
fects, and will rise or fall according as the impressions of cold
or heat sent from the sky chance to predominate. If the light
reflected down from the heavens be profuse, it will excite
more heat than the simultaneous frigorific impressions can de-
stroy. Under a canopy of fleecy clouds, a considerable excess
of heat is hence excited on the black ball ; but when the sky is
clear, the influence of cold generally prevails, increasing as;
the sun declines.

The question is now to discover the cause of the phenomena
which have been thus revealed. I have already stated, that
different experiments appeared to concur in indicating the cold-
ness of the superior atmosphere as the source of those effects.
Since pulses are darted from such various surfaces, and since
the softness of the external coat, and its tendency to fluidity,
seem vastly to augment their power ; may they not likewise be
excited from a boundary of air itself? This extension of a
great principle in the economy of Nature, has never yet been
surmised ; nor can it be readily brought to the test of direct
experiment, since a body of air, whether hotter or colder
than the general medium, would evidently not remain station-
ary, but continually rise or fall.

I sought accordingly to examine the effect of directing the
zethrioscope to a hot stream of ascending air. I placed on bricks

before that instrument, the lower part being screened, a large ~

mass of iron carried from the fire, at almost a red heat.
The zthrioscope then gave impressions of heat or cold, ac-
cording as its aperture was without or within the warm cur-
rent, or was affected by the anterior or the posterior boundary.
But this experiment proved very troublesome, and occasionally
turned out alittle unsatisfactory. Another experiment per-
formed out of doors, to try the action of hot smoke raised from

a

omy

i—_
ve

Ss EY

aver

4S"

ine saith

FROM THE HIGHER ATMOSPHERE. 489

a train of damp straw set on fire, was, from the difficulty of
managing it, found to lead to no certain conclusion.

But during winter, a much easier mode occurred for decid-
ing the question. In a room where a steady fire was kept up,
the sectoral aethrioscope was set on the inside of the window,
and directed to the upper part of the opposite wall; but on
throwing up the window, the instrument being now surround-
ed by a body of cold air, which, however, did not penetrate far
into the room, the liquor sank 5 or 6 degrees, indicating im-
pressions of heat, caused evidently by the excess of tempera-
ture of the remote air of the room above that which was con-
tiguous to the aethrioscope. It need hardly be observed, that the
effect increased in colder, and diminished in milder, weather.

A similar experiment is readily performed by help of the erect
zthrioscope. In a close apartment, where a good fire is con-
stantly kept up, the ceiling and the floor may be discovered by
the pendant differential thermometer to have exactly the same
temperature with its adjacent stratum of air. Yet the upper
portions of the confined air of the room will be found several
degrees warmer than the lower. Instead of being divided only
into opposite ranges, the whole mass, from the floor to the ceil-
ing, will, in consequence of the expansion and buoyancy of its
heated particles, form a series of intermediate strata, not dis-
tinguished, however, by any very precise boundaries. But the
intensity of action being proportional to the difference of tem-
perature, the effect on the zthrioscope must evidently be the
same, whether it is produced by a single set of large pulses or
by several sets of smaller ones. If, for example, instead of one
bounding surface, above which the air is seven degrees warm-
er than immediately below it, we suppose seven such boundaries,
each having an excess of temperature of only a degree: the
pulses excited at the first of these intermediate surfaces, and
‘successively augmented as they reach the second, third, and

Vor. VIII. P. If. 3Q fourth,

490 ON IMPRESSIONS OF COLD

fourth, &c. surfaces, will at last acquire the same energy as if
the ageregate difference of seven degrees had been all exerted
at once. Thus, the under surface of the stratum G (see fig. 2.
Pl. XI.) darts pulses downwards, which, being augmented in
succession at the under surfaces of the strata I’, E, D, C, B, and
A, may have finally the same intensity as if they had originated
from the opposition of the extreme strata G and A. Accord-
ingly, having planted a large screen immediately before the
fire, and placed a delicate pyroscope about the middle of the
room, with a broad circular piece of metal suspended a few
inches above it; on withdrawing this canopy after some time,
the instrument indicated a small impression of heat, seldom
exceeding, however, one degree. But the effect may be ren-
dered more sensible, by a moderate concentration of the power
excited. Thus, the hemispherical pendant athrioscope (fig. 6.)
will, in the same situation, mark a very sensible calorific impres-
sion, amounting, at least in ordinary cases, to three or four
degrees. Hot pulses are, therefore, actually shot downwards
from all the upper strata of the confined air of a room in which
a fire is kept steadily burning.

The experiment can be likewise reversed. Let an inverted
zthrioscope, composed of a pendant differential thermometer,
have its sentient ball fitted with a small hemispherical cup which
is turned downwards, (see fig. 7.) This instrument being set on
the floor, will remain at zero ; but if lifted only a few feet, it will
indicate a visible impression of cold received from below, which
will increase to three or four degrees when the zethrioscope is
suspended near the top of the room. Wherefore, the upper
surfaces of the successive decumbent strata, being comparative-
ly colder, send upwards a series of chilling pulsations. Each
of the conterminous boundaries appears thus to perform a
double operation, ‘shooting downwards impressions of heat, and
darting upwards equal impressions of cold. Such a mutual

exchange

PSS oe

FROM THE HIGHER ATMOSPIERE. 49]

exchange of influence must evidently tend to accelerate that
progress to an equilibrium which the gradual intermixture of
the different strata, if left quite undisturbed, would in time
produce. The air of a close apartment, exposed to the action
of a steady fire, is hence kept agitated through its whole mass
by a series of opposite tremors, which continually disperse, in
all directions, the irregularities of temperature.
_ If the action of the pulses excited in the air of a small room
be made thus apparent, how much more striking should we
expect to find the effect produced by the mingled tide of
commotion collected from the vast body of the atmosphere
itself? Taking even the lowest range of strata, to the height
perhaps of two miles, including scarcely one-third part of
the whole aérial mass, the difference of temperature between
its extreme boundary will amount to 20 centesimal degrees,
or 36 on Fahrenheit’s scale. The order of the series, however,
is exactly the reverse of what takes place in a close room, the
air of the superior regions being invariably colder than at the
surface of the earth. Accordingly, the simple pyroscope, ex-
posed in calm weather to a clear and open sky, will, at all
times, if not disturbed by the influence of a strong light, indi-
cate large impressions of cold, amounting to 5 or perhaps even
10 degrees. In most cases, it may be sufficient to screen this
instrument from the direct action of the sun’s rays. But the ac-
tion of light will be almost neutralized, by opposing a diapha-
nous ball to one gilt with silver, or contrasting a ball of the
different shades of green or blue, to another coated with pure
gold leaf. But to procure consistent results, it is still more
necessary to guard against the deranging influence of winds.
The same sectoral form of the athrioscope discloses also the
peculiar influence of clouds in obstructing the frigorific pulses
excited in the atmosphere. When the sky was completely ob-
scured by a dense canopy of clouds, the instrument being
3Q2 pointed

492 ON IMPRESSIONS OF COLD

pointed to the zenith, marked only five millesimal degrees ;
but, on lowering it successively to the angle of 30 degrees
above the horizon, it continued to indicate still the same effect.
Water almost completely absorbs the pulsatory impressions of
heat or cold ; and may not clouds, consisting of diffuse aque-
ous particles, produce a similar effect ? But the feeble action
of five degrees, amounting scarcely to the eight part of what is
observed in clear weather, could not be any remnant of the
pulses from the higher celestial regions, which had penetrated
through the mass of vapours ; because, if the vertical transit,
through the obstructing range, allowed only an eighth part to
escape, the oblique passage of 30 degrees, redoubling the ex-
tent of absorption, would have reduced the final discharge to
five-eighths of a degree. The impression measured by the
zthrioscope, in this case, must therefore have originated wholly
in the strata of air between the under surface of the clouds
and the ground. But in that narrow space, the extreme diffe-
rence of temperature would be comparatively small. Hence
the frigorific action is found always to diminish as the clouds
descend. Nor does their variable denseness appear materially
to affect the result, which is often the least, when a very thin,
whitish, but low vapour, gathers in the atmosphere. Hence
the ethrioscope might, with great facility, be employed in es-
timating the altitude of clouds.

As the higher strata of the atmosphere thus dart cold pulses
downwards, so the lower strata must evidently project equal
pulses of heat upwards. But to measure these, it would re-
quire, as in fig. 7. the zthrioscope to be inverted and furnished
with a pendant differential thermometer. The instrument, now
carried to the top of a lofty mountain, and directed to the plain
below, would indicate a considerable impression of heat, nearly
proportional to the quantity of ascent ; and, therefore, amount-
ing, for example, on the summit of Chimboraco, to perhaps 20

millesimal

FROM THE HIGHER ATMOSPHERE. 493

millesimal degrees. But, in the same situation, the common z-
thrioscope might, be expected to mark an impression of cold
from above, as just so much diminished. No opportunity,
however, has yet occurred, on a large scale, for making these
interesting observations. The ascent of a balloon would afford
the readiest mode of verifying and extending the theory. |

. The nature and intensity of the cold and hot pulses excited
in the several strata of the atmosphere, may be easily under-
stood from (fig. 9. Pl. XI.) Let two equal and opposite
circles touch the straight line AB, which divides a stratum
of cold, from another of warm, air.. While the opposite dia-
meters CD and Cd represent the forces of the perpendicular
pulses of cold darted downwards, and of heat shot upwards, the
chords CE, CF, CG, and CH, and Ce, Cf, Cg, and Ch, will

likewise exhibit the strength of the Pulees which are transmit-

ted with various obliquity.

- The:inverted zthrioscope likewise disiayews the quality and
measure of the pulses projected from the ground. These, in
general, are: very feeble, seldom in this:climate exceeding three
or four degrees. In the progress of a bright day, as the ground
grows warmer than the incumbent air, it excites hot pulses ;
but, as the sun declines, the effect gradually diminishes ;
till this again returns, increasing with a contrary character,
when the surface of the earth has become relatively colder.

The same instrument being suspended a few feet above the
ground while the sky appeared clear and blue, a silver tray
was laid upon it, and the reflected impression of cold amount-
ed to 25 degrees ; but, on interposing a plate of glass, it was re-
duced to two degrees; and on removing this, and pouring a
sheet of water over the silver, the effect was absolutely extin-
guished. The absorbent influence of water, and consequently
of clouds, was thus distinctly shown.

The

494 ON IMPRESSIONS OF COLD

>

The zthrioscope thus opens new scenes to our view. It ex~
tends its sensation through indefinite space, and reveals the
condition of the remotest atmosphere. Constructed with still
greater delicacy, it may perhaps scent the distant winds, and
detect the actual temperature of every quarter of the heavens.
The impressions of cold which arrive from the north, will pro-
‘bably be found stronger than those received from the south.
But the instrument has yet been scarcely tried. I am anxi-
ous to compare its indications for the course of a whole year,
and still more solicitous to receive its reports from other cli-
mates and brighter skies *.

All those effects are no doubt more conspicuous in the finer
regions.of the globe. Accordingly, they did not escape the ob-
servation of the ancients, but gave rise to opinions which were
embodied in the language of poetry. The term Azg was ap-
plied only to the grosser part of the atmosphere, while the
highest portion of it, free from clouds and vapour, and border-
ing on the pure fields of ether, received the kindred appella-
tion of Aide. But this word and its derivatives have always
been associated with the ideas of cold. The verb c&asbeimZm is
adopted by Athenzeus, to signify the cooling of a body by mere

exposure

* In this stage of the inquiry, it may be proper to notice a singular observation,
which I have not yet had an opportunity of repeating. An ethrioscope exposed to
the free air, on a platform projecting towards the north, from the window of my ex-
perimental room in Queen Street, stood a few weeks since, in a clear frosty day, at
about 25 degrees; but, on the approach of evening, a light wind having suddenly
turned to the opposite point of the compass, the atmosphere became at once obscu-
red by a body of very thick and dark smoke: the liquor, contrary to all expecta-
tion, immediately rose more than 10 degrees, and remained stationary till the
dense mass again disapersed. This stratum of fuliginous matter would no doubt
absorb the frigorific impressions showered from the sky ; yet being precipitated by
its collected weight, it would bring down intense coldness from the superior re-
gions, and therefore dart new impressions, rendered the more powerful from the

proximity of their source.

FROM THE HIGHER ATMOSPHERE. 495

exposure under a serene sky. Homer uses the term Ajégos, in
speaking of the reception of his hero, when overcome with
cold and toil*. The same graphic poet applies the epithet
Aibenyevns or Aidenyevélns, or frigorific, to Boreas, the north wind f.
The Chorus, in the Antigone of Sornoctes, deprecates alike
the pelting storm and the cold (aiégia) of inhospitable frozen
tracts t. The word asdgios is employed by Herovorus, to signi-
fy a chill, as well as a dry, Of the same import
is the expression in Horace—Sub Jove yaar

But the facts discovered by the athrioscope are nowise at
variance with the theory that regulates the gradation. of
heat from the equator to the pole, and from the level of the
sea to the highest atmosphere. The internal motion of the
air, by the agency of opposite winds, still tempers the dis-
parity of the solar impressions ; but this effect is likewise ac-
celerated by the vibrations excited from the unequal distribu-
tion of heat, and darted through the atmospheric medium with
_ the celerity of sound. Any surface which sends a hot pulse in.
one direction, must evidently propel a cold pulse of the same
intensity in an opposite direction. The existence of such pul-
sations, therefore, is in perfect unison with the balanced system
of aérial currents.

ee Ot A, Sh ee ee Bhs i pe
* Albeo wok xara Dedpentecvov ley & olxoy. Odyss. Lib. xiv. 318.
T (Qs OF are recePetcel uPeédes Ards exzrostovlecs,
Yuet imal frags aibenlevios Bogieo Iliad. Lib. xix. 357-8:
Keel Boging wibenyeverns, wiya xtux xvawday. Ody lyss. Lib. v. 296...
$ Avoabaray motryor cebgsa

Kas durope Bee Pevryety Bern. Antigone, 357.

|] QOsguedlegos yag On ess ro bdwe vs ve aiderec naa rhs Ogore. Euterpe,

XXII.

el
a tae Mone

A a rolenene
oda th
ve

gta

Feel faa rere titer eo Deiriaiise

7" srenert li; od pened
ia en ty oi “a rg
bt oh Rae
“TRI le 14 ay beh ie
AG LEK ce tiga ier

Po ee 4

XXII. A Method of determining the Time with Accuracy, from
a Series of Altitudes of the Sun, taken on the same side
of the Meridian. By Major-General Sir Tuomas Bris-
‘BANE, Knt. F. R.S. E.

(Read Feb. 2. 1818. )

i: for a number of years been constantly moving about,
in situations where I could not convey large astronomical in-
struments, I have repeatedly tried to what extent of accuracy
and consistency I could arrive with the smaller ones. The re-
sults have convinced me, that a great deal of accuracy may
in that way be obtained; and that the sextant is an instru-
ment, which, if perfectly understood, would be in higher esti-
mation, and more general use, than it is at present. The ob-
servations I am about to submit, were made with a ten inch
sextant of Troughton’s, divided on platina to 10”, (No 1200).
The manner of using it, which I am now to describe, is what
T have pursued for a great length of time, both at sea and at
land, and I can recommend it as uniting simplicity with accu-
racy, and at the same time as serving to discover errors, if they
happen to exist. Our climate does not admit of obtaining equal
altitudes very frequently, but I conceive that the mode which
I wish to see adopted, will admit of equal accuracy, and I am

Vou. VILL. P. II. ee ie justified

498 ON FINDING THE TIME ACCURATELY

justified in this conclusion, by the results of many hundred trials,
verified by calculating as simple altitudes those from which I
had deduced the time as equal altitudes. Indeed I am rather
disposed to give the preference to the simple altitudes for ac-
curacy, if a considerable change of temperature has taken place
between the morning and evening observations, as the conse-
quent change of refraction is seldom taken into account in
the calculation of the equations to equal altitudes, though it
may produce a sensible effect on the determination of the
time. To overcome these difficulties, has been my sole.object,
and my only wish, in making this communication, is to enable
every observer to put this method to the test, in the hope that
he may derive the same satisfaction from it that I have done.
In the morning, when the sun has nearly 10° of altitude,
and farther from noon than two hours, if far advanced in the
season, but otherwise, the nearer the prime-vertical the bet-
ter, I observe eleven successive altitudes of the sun’s lower
limb, reflected from quicksilver, where the situation will admit
of it; where it did not, I have employed with equal success
pure limpid oil covered by one of Troughton’s plate-glass an-
gular roofs ; but in most situations it may be used in a room,
without any cover; always taking care, in the morning obser-
vations, to set the index, with the utmost accuracy, to an even
10’ or 20’ greater than the sun’s altitude, and then to wait the
contact. If I use a chronometer, I have an assistant, who
counts the seconds aloud, which I direct him to note, with the
fractions, &c. at each observation. In the afternoon I pro-
ceed in the same way, only setting the sextant 10’ or 20’ less
than the sun’s altitude, and carefully noting the barometer and
thermometer, for each series of observations, in order to cor-

rect the mean refraction.
I

WITHOUT EQUAL ALTITUDES. 499

I send you a type of the calculation complete, in order that
any one who wishes to pursue it, may easily be enabled to put
it in practice. As the altitudes are all successive, the inter-
vals ought to be nearly equal ; by which means, merely casting
the eye over the results, you readily discover any inconsisten-
ey, if it should exist. Although there may appear a number
of figures in the work, it is extremely simple, as I have only to
combine the error of the instrument with the refraction, paral-
Jax, and semi-diameter of the sun, for the first and last obser-
vation, the tenth part of which difference must be equally dis-
tributed throughout the series, in order to obtain each altitude ;
and the same system applies to the rest of the work. As the al-
titudes increase or diminish by a uniform quantity, their natural
sines are all taken out at the same opening of the book, and the
proportional parts for seconds, applied as appears in the mode
I have adopted, and have herewith transmitted. The
Table entitled Logarith. Rising, in the Requisite Tables, al-
though perfectly equal to all nautical purposes, I did not consi-
der as sufficiently extended to give the tenths of seconds, which
modern instruments and Logarithmic Tables afford the means
of arriving at. I therefore computed a Table entirely a-new,
from the formula

sin. (co. lat. + dec. ©) — sin. (alt. ©) ,
cos. lat. x cos. dec. © i

2 sin.* (4 a) =

but taking the logarithms from tables to ten places of figures,
although only retaining eight for those in the computation,
as being sufficient to give me the last figure correct. These
Tables begin at 2h. from Noon, and are carried on to 6 h., and
to every 10’, with the differences corresponding. The re-
sults were proved by the first and second differences, and
lastly, by comparing the first five figures with those given in the

Requisite

500 ON FINDING THE TIME ACCURATELY, &Xc.

Requisite Tables. The Table of natural sines given in the Ap-
pendix to that work, is most convenient for the calculation of
the time by this method. If this communication is thought
worthy of a place in the Transactions of the Society, of which
I have the honour to be a member, I shall have the satisfaction
of making another, respecting the mode of determining lati-
tudes by the sextant most correctly, by a series of observa-
tions made near noon. [I should also wish to submit a paper
on the Repeating Circle, and the extraordinary accuracy of the
results I have obtained from observations made with a circle
of Troughton’s, twelve-inch in diameter, if the Society shall
think the matter deserving of its attention.

Paris, 23d November 1817.

The

[ Vol. VILE. Part II.—p. 501.]

The following are the Times and Altitudes of the Morning and Evening Observations, from which the Calculations of the Times Srom

8h 41’ 49".7 23° 10°

42 34.3
43 17.3
4413
44 46.3
45 30.3
46 16.3
47 13
47 45.3
48 29.3
49 15.3
50 13
50 46.3

oe
Gd! 8 0 thc

2»

20
30
40
50

0
10
20

~ 30

40
50

0
10

Equal and Simple Altitudes have been deduced, as referred to in the respective Calculations.

Qh 56’ 39''.3.

- 55 54.3
- 55 10.3

Ana og a o

54 25,0
53 41.4
52 58.3
52 11.8
51 26.0
40 42.0
49 57.0
49 12.0
48 26.4
47 40.7

Barometer, Morning Observation, 748.30

Thermometer, do.

Barometer, Evening Observation, 745.60

Thermometer, do,

10.3

14,00

8b 41/ 49'".7
2 56 39.3

11 38 29.0

40 14.5
14.3
13.8
13.2
13.8
14.3
13.8
13.6
13.7
13.1
13.7
13,8
13.5
49.1

_——_

11 49 13.77

Calculation of Time, from Equal Altitudes.

© Longitude 74 14° 7

34.3 17.3 13 46".3 30".3 167.3 1.3 45°3 29°83 15°83 13

54.3 10.3 25.0 41.4 58.3 11.3 26.0

28.6 27.6 26.3 Q1.7 28.6 27.6 27.3
143 13.8 13.2 13.8 14.3 13.8 13.6

11 49 13.77
+ 17.68

11 49 31.45

42.0 57.0 12.0 26.4
27.3 26.3 27.3 27.7
13.7 13.1 13.7 13,8

8n 46’ m. Time, Morning Observations.
14 52 m. Time, Evening Observations.

“6 06 Interval,
3 03 4Interval.

[Vol. VILL. Part I1.—p. 502.]

CALCULATION FOR FINDING THE

81.2 Mean E. A. T. = 10/28” .12

Chateau de Sainte, Pas de Calais. Morning Observations. Very Clear.

841497 42343 49178 444 15 44-463 45 903. 46.168 47 15 OT -
3100 320 2330 93 40 23.50 2% 0 410 220 24 SI
— 6 Error. { Daily var. @’s decl. 17 55 = ot FREE

; 5 19 15 ; 37 36 0513841 4.052805¢
23 040 se led 0 i 24 50634863 5.063486
23 040 85224 8 59 49 $.1462789, 2.1287H07
11 32 0 307 36-3 00 11 140 0 GEN
+ 11 45.5
lH 45 1148473 1153491 1158509 123527 128545 1213 564 1218 58
©'s declin. first obser. 16 14 17 co-sine 9.9823202 @’s declin. last obser.16 14 22 5 Co-sine, ean
Co-ar. co-sine, co-lat. 50 19 57 0.9149539 - - - - - - - - .
0.2126337 0.2126371
©’s declin, first obser. 16 14 17 Last observ. 16 14 22.5
Co Latitude, 39 40 3 39 40 3
@'s meridian alt. = 23 25 46 Nat. sine 397619 93 25 40.5 Nat. sine 397594 Differ. 25
*s mer. alt. Ist obser. 23 25 46 Nat. sine 397619 397617 397614 397612 397609 397607
pase Seale a ll 43 455 “7 203072 204496 205920 207343 208765 210187
194547 193121 191694 190269 188844 nBeeu
Prop. parts for seconds of alt. 45.5 9 = 216 225 233 243 251 259
194331 192896 191461 190026 188593 187161
Log. - = = = 9.288542 9.285323 9.282080 9.278813 9.275526 9.272215
Co-ar. co-sine, co-lat, ©’s declination, 0.212634 212634 212654 212634 212635 212635
Horary. - - - 9.501176 497957 494714 .491447 Ee 61 484850
; 0975 H $ t
TWAS — | i H }
1454} H i H
t ; H H
556 | i
3.7428 3 6586 3 6143 3 52993 4455 3 4 09
852172 853014 85345.7 854301 8 55 59.1 8 5559.1
8 41 49.7 42 34.3 4317.3 44 13 4446.3 45 30.3,
10275 10271 10984 10288 10282 10 98.8
Q7.1
28.4
28.8
28,2
28.8
27.6
274
28.5
28.9

TIME WITHOUT EQUAL ALTITUDES.

@ Tth Nov. 1517, Lat. 50°19 57” Long. 2’ in ‘Time west of Pans. Error of Inst. — 6’

48.293 49155 Ther. 103 9.9995 9.9995
24-40° 2450 Bar. 74830 9.9931 9.9981
Error, — 6 8D. - %8 2.4280. ‘77 2.3986
28 172 38 218
24 44
12 22 24378 2.4080
+1236 -
re 2741 Refrac. 255.9
12 343 6 87 Paral. 86
12 25 59.9 12°29 1.8 965 4 Ref.- 247.3 -
— 425 4 Par. + 4 75
©’s semi-diameter, + 16 10°9 16 10.9
4-11 45 5 + 12 03.6
©’s declin. at noon, 16 16 37 16 16 37
3) 7 36 “= 2 20 SOP = 2 14.5
16 14 17 16 14 22.5
897604 3897602 397599 397597 897594
211609 213030 214451 216156 217575
185995 184572 183148 181441 180019
269 276 285 8 17
185726 184296 182863 181433 180002
9.268873 9.265522 9.262126 9.258716 9.955277
212635 212636 212636 212636 212637
481508 478158 474762 471352 467914
} } } $ 471
H H H H 761)443(5.8
{ } ; H 3805
; H
H { H 625
$ ; ‘ $
3 3161 3 23135 8 1462 3111 8 0158
85643.9 85728.7 858138 358589 859442
4616.3 47 1.3 47 45.3 48 29.5 4915.3
10 27.6 10 27.4 10 28.5 10 29.6 10 28.9

CALCULATION FOR FINDING DHE LIME WinHouT EQUAL ALTITUDES.

Calculation for the Evening Observations.

(Vol. VIII, Part IL—p. 503.)

Times, = 249120 49570 50420 51260 52
s 113 52583 538414 54250 55103 55 643 56 39 3 Th . 14 0 = 9.9934
Altitudes, we! a0 24400 24300 24200) 24100 24 00 23500 98400 23800 982900 98100. Bar 745 60 = 90916 eee
. Error— 6 3D. 77 = 2.3936 78 = 2.4280
} 24 44 0 O's daily var. 17 89 Log. = 3.0253059 17 39 Log. =8.0258059 283. 04 pHing = 112
*}2 22 0 25941 40326590 3 78 4.050304 11 82 0 2.4004 2.4302
24 5.0634863 24 5.0634863 } 45} 7 269’ 3
21214512 2.1390946 H — bey UJ
1823 =2123 137 8 =2178 i 242 7 260 6
Leroi, 1 a 0 — 4 27 Refrac. Paral.— 4 20 6
+ 11 503 16 10 . idi
12 22 0 + 16 9 ©’s semidiam. + 16 10 9
+ 1282 11 43 503 12 82 11 503
Altitudes corrected, 125482 12 29964 122446 121928 121410 128592 123575 1158557 1153539 11 48521 n 43 50 3
©’s declination, 1st observation, = 16 18 49 Co-sine = 9.9821530 Last GEGRLBES WY 18 55 Co-sine = 9.9821493
Co-latitude, co-sine, ar. co. 839 40 08 0.1949539 = a - - 0.1949539
0.2128009 0.2128046
©’s declin. 1st observation, 16 18 49 Last observation, 16 18 55 cosme
Co-latitude, = = 39 40 03 = e 2 39 40 03
23 21 14 N. sine 396409 23 21 08 Nat. sine = 396383
©’s mer. alt. 23 21 14 Nat. sine 396409 396406 396403 396401 896398 396395 396393 396390 396388 396385 396383
12 34 8 217575 216156 214735 213315 211893 210187 208765 207343 205920 204496 203072
178834 180250 181668 183086 184505 186208 187628 189047 190468 191989 193811
Proportional parts, - - 39 80 17 13 5 281 QT2 265 257 247 239
178795 180220 181651 183073 184500 185927 187356 188782 190211 191642 193072
Logarithm, - - 9.252355 9.255803 9.259238 9.262624 9.265996 9.269343 9.272668 9.275961 9.279236 9282491 9.285719
Ar, co. co-sine, co-lat, — sun’s decl. 0.212801 0.212801 0.212802 0.212802 0.212803 0.212803 0.212805 0.212804 0.212804 0.212805 0.212805
9.465156 9.468604 9.472040 9.475426 9.478799 9.482146 9.485471 9.488765 9.492040 9.495296 © 9.498524
4418 i $ H i { j i 058
== 3 H 3 H =
764)73809 7 H H H i i ; H 780)466(6 4
6876 H H i ; i { i 4380
soo i H i i i i i 280
‘ 30%9 $1102 31850 5 2399 3 3 246 3492 8 4536 8 5879 8 6228 37 64
ata a 3 34057 0 250420 251260 262113 52583 253414 254250 255103 255 543 256393
10° 27 7 1027 9 10282 10 290 10 286 10 263 10278 10 286 10276 10280 10271
27 9
28 2
29 0
28 6
26 3 aren recerees E. — Apparent Time, - = 10’ 27’88
27 8 Es E. — by mean morning pbseryation: 10 28 12
98 6 Mean of both, " - 1 ai " 10 28 00
Apparent noon simple alti-
28 0 aR tudes, vt - ll 49 32 00
27 1 Ditto by cul altitudes, same
11)306 8 day, 11 49 31 45
Difference from equal altitudes, + 65

(Vol. VIII. Part II.—p. 504.)

‘Times, =) 8*1'524.8 2 R8".2 3/3'.8 53 39.3 4 18.4 4 48.3 5 24.3 5 59.3 6 36.3 tf 11.8 q 46.8
Altitudes observed, 38° 195 88° 20) 88° 80’ 38° 40 88° 50’ 39° 00' 39° 10’ 89° 20 39° 30 39° 40 39 ne Suecein farcnntink ea
un’s declin. at noon lod
$*46' 48" before noon, + 3.41 — 8354
oe of Refraction — Parallax — 2/37".4 Also — 2 29.7 a fd Fae ane F
Semi-diameter, +15 59-5 15 59.5 un’s . corrects 44 30 0 44 36.6
Correction for Refr. Parallax, 13 22 & semi-diameter. ee re Ms 4 ss + 18 29.8 Semi-diam. Paral. & Refrac. Cosine, - ; 9999636 i 635
ibe 3 298 re coe 1981520 01951520
; eee sees Ae 221 + 99, . co, cos, Lat. 1.195152 . 52
True Altitude, - 19 15 22 20 05 29.8 True Alt. Sun’s Centre. eo
. 0.1951884 0,1951885
Co.-Latitude, - 39° 38/45” 89° 38 45”
Sun’s declination South, 0 44 30 0 44 35.6
Sun’s Meridian Altitude, 38 54 15 38 54 09.4
Nat. Sine, - - 627963 627963
Proportional parts for /’ + 59 Diff, proportional parts, = 23 36
628022 62799
$
H
H
Co-Latitude, a 39° 38° 45! FER REREETAREREHAHSERESES FRESHEST U ERE EES R eR HEE EEE EEREEE HEE BEBESESE EEE HEHEHE SESE EES EDERESSMENESSOREEY ? seneeegeee Petre ee eeeee Dense etna een eae shemerawennee Seen eee ee eeeeee
¥ in. S. - 7 t wot Me
Sun's 0 4430 The 23 Proportional Parts for difference of Sun’s declination to be equally distributed from first to last Observation.
Fans Meridian Altitude, 38 54 15
at. Sine, 5 = 628022... 628020 628017 628015 62 3
pay ts 0 28013 628010 628008 628006 628004
N, sine Ist Alt..19°16/ 22 629691 331068 332436 333807 335178 336548 337917 539285 340653 ee ite
Difference - - 298331 296957 295581 % j 1
= ’ Aa b 94208 292835 291462 290091 288721
Prop. parts for N. sines, 100 103 107 il 114 118 121 125 kis er 7 ae
Log. : 298231 296854 Q95474 294097 2 a
: ets 296 295 29409 92721 291344 289970 288596 28722:
ASR ei a eubas parahae 9,4705194 9.4684906 9.4664539 9.4644662 9.4623531 9.4602903 SASERI0S 9. 4561852 9. ree
. dat. 0.192 1951884 0.1951884 0.1951884 0.1951884 0,1951844 0.1951885 0.1951885 0.1951885 0.1951885 0.1951885
9.6697412 9.6677314 ——— —— :
iva ui 9.6657098 9.6636790 9.6616423 9.6595946 9.6575416 9.6554788 9.6534078 9.6513237 9.6492342
—- 9839
572)4288(7'.4 a503(
4004 590)2508(4.2
2360
234 Lee
143
Time from Noon, - 3 51 17.4 3 50 42.3 3 50 0 ¢
Times of Observation, 8 8 426 TL 3 49 31.9 3 48 56.7 $ 48 21.3 8 47 46.10 8 47 10, ‘
cktanceaeter "Tinea, niniiscts 8 oe a : 9 52.9 8 10 98.1 811 33 8 11 38.7 8 12 140 8 iz ra 3 ie Pe 3 4 ong 3 is aes
SAE 2 S§ 8 38 8 3 398 8 413.4 8 04 48.3 8 5 243 8 5 593 8 6 363 8 7118 8 7 463
Chronometer — App. Time, 6 49.8 6 49.5 6 49.6 6 43.8 6499 e504 Py = —— a
7a i 6 49.7 6 50.1 6 48.5 6 48.9 6 49.5
49.6 u
48.8
ans Result of Equal Altitudes observed the same Day with Sextant. Sun’s Longitude 6s 2° 0’
50.4 10» 42’ 057.3 28°3 11’3 BY 35".3, 120°.3 4.3
49.7 1 2554 108 a8. i d ) ‘ rae ys tei Middle Observati 3
50.1 iiss = pes, ee ge 20,0" 33.3 50.6 "73 ete le Observations,
48.9 11 45 40.7 39.1 39.8 41.6 39.6 40.3 37.6 "89.0 589. 38.6
49.5 == 49.5 49.9 50.8 47.8 gon a) Bao i
ee 11 52 50.3 : et oe a2) 494 49.8 eat
10)6 496.2 49.5 ll 52 49.77 d ,
— 49.9 + 18.03 Equation of Equal Altitudes.
Men, - - - = 6 4962 50.8 zeadies
Rate to Noon, =~ 61 49.8 11 53 07.80 Mean of Apparent Noon, by Equal Altitudes.
Difference of Meridians, — .06 DO EM hes tenatehecares 11 53 07.80 —_—_——. Simple Ragin with Sextant.
Reduction of Equation to Noon, + 3.25 48.8 H
a 49.5
0 6 52.20 49.4 i
11 53 07.80 by Chronometer. 49.8 $

App. Noon, rs

CALCULATION FOR THE TIME WITH AND WITHOUT EQUAL ALTITUDES.

Valenciennes. % 25th September 1817.

Valenciennes, 25th September. Very clear.

Mode of determining the Time by a Sextant of TnrovcHton’s, No. 1200.

Latitude 50° 21/15” Longitude East of Paris 4’ 44!” in time.

11 52 49.77 Mean.....-+

App. Noon 1]» 51’ 41".7

ie

XXIII. Observations on the Junction of the Fresh Water of Rivers
with the Salt Water of the Sea. By the Reverend
Joun Fiemine, D. D. F. R.S. Eni.

( Read June 17. 1816.)

I. is possible, that the following observations may contain
little that is new to those who are familiarly acquainted with
the details of the science of Hydrostatics. But as I have not
met with any remarks on the subject, in the course of my li-
mited reading, the experiments which were performed, and the
conclusions to which they lead, are here submitted to the con-
sideration of the Royal Society.

When the flux of the tide obstructs the motion of a river,
the wave has been supposed to produce its effects in the same
manner as a dam built across a stream. This popular opinion,
however, appears to have been adopted without sufficient con-
sideration, as it can only hold true, in those cases, where the
opposing fluids are of equal density, but never at the junction,
of opposite currents of fresh and salt water, which are of diffe-.
rent densities. In this last case, where currents of fresh and
salt water come in opposition, the lighter fluid, or the fresh
water, will be raised upon the surface of the denser fluid, or.

Vou. VIII. P. I. 358 the

508 JUNCTION OF THE FRESH WATER OF RIVERS

the salt water, and when the stronger current of the tide has
reversed the direction of the stream, the salt water will be
found occupying the bottom of the channel, while the fresh
water will be suspended or diffused on the surface. This view
of the matter occurred to me in 1811 ; but it was not until the
29th of September 1813, that I had an opportunity of verify-
ing the conjecture, by an examinatien of the waters of the
Frith of Tay.

Flisk Beach, opposite to which the experiments were made,
is situated a considerable way up the Frith, being upwards of
sixteen miles from Abertay and Buttonness, where the Frith
of Tay actually joins the German Ocean. The channel of the
Frith at this place is about two miles in breadth ; but upwards
of a mile and a half of this extent consists of sand-banks, left
dry at every ebb of the tide, and during flood, covered with
from three to ten feet of water. These banks are separated
from one another by deep pools, or /akes as they are termed,
which occasion great irregularities in the motion of the cur-
rents. The channel of the river is near the south side. It is
about half-a-mile in breadth, having in the deepest part about
eighteen feet of water, when the tide has ebbed, and upwards
of thirty feet during flood.

The apparatus which I employed was very simple: It con-
sisted of a common bottle, with a narrow neck, having a weight
attached to it. Besides the cord by which the bottle was low-
ered, there was another connected with the cork, in such a
manner, that I could pull it out when the bottle had sunk to
the place of its destination. . The weather was favourable, and,
on the day of the experiment, there was no wind to disturb
the surface of the stream.

With this apparatus, I proceeded to the middle of the chan-
nel of the river, at Jow water, when the current downwards had

ceased.

» WITH THE SALT WATER OF THE SEA. 509

ceased to be perceptible in the boat at anchor ; and I obtained
water from the bottom, the middle, and the surface of the
stream. The water taken from the surface of the stream, was
fresh, and tasted like ordinary river water. The water taken
from the middle, was not perceptibly different ; but that which
was brought frem the bottem was sensibly brackish. The wa-
ter from the surface did not coniain any salt, as a thousand
grains of it, when evaporated with care on a sand-bath, left on-
ly a grain and a half of residue, apparently mud, which, when
applied to the tongue, communicated no impression of salt-
ness. The water from the middle of the stream yielded two
grains of residue, when the same quantity was evaporated, of
a whiter colour than the former, and having a perceptibly salt
taste. ‘The water from the bottom, which was saltish even to
the taste, yielded four grains of saline matter. According to
these experiments, the layers of water were arranged accord-
ing to their densities, the heaviest water occupying the bottom
of the stream, and the lightest floating on the surface.

At halflood, I repeated the experiments on the waters ob-
tained from the same situations as before. The water at the
surface had now become very sensibly salt to the taste, and
thus gave decided proofs of the progress of the tide. The
three bottles of water now obtained, yielded results, not
in unison with those already taken notice of. The arrange-
ment of the different strata of water, according to their den-
sities, as observed at ebb-tide, was in some degree rever-
sed; for here the water at the surface was salter than that
which was obtained from the bottom, and the water from the
middle was salter than either. A thousand grains of water
from the bottom, yielded by evaporation only ten grains of sa-
line matter, while the water from the surface yielded eleven
grains, and from the middle twelve grains, by the same pro-.

cess.
S5'2 This

510 JUNCTION OF THE FRESH WATER OF RIVERS

This anomaly is easily accounted for. Were the current of
the tide confined entirely to the channel of the river, an ar-
rangement of the waters, similar to that which existed in the
first experiments, would have prevailed. But during the flow-
ing of the tide, the sea-water soon occupies more than the
channel of the river, and spreads itself in various streams
among the hollows of the sand-banks. These streams reunite
at different places with the principal current, and, in this man-
ner, prevent the salt and fresh waters from gaining their natu-
ral relative position. But as soon as these sand-banks are co-
vered with water, the tide proceeds with regularity in its
course, so that the different layers of water can then arrange
themselves according to their specific gravities.

A thousand grains of water obtained from the bottom, at the
height of flood, yielded by evaporation twenty-three grains of
salt, while the same quantity of water from the middle yielded
only eighteen grains; and from the surface only seventeen
grains. This was a difference of no less than six grains, and
seemed to afford a decisive result.

In order, however, to complete the series of observations,
I examined the conditions of the currents at half-ebb. The
same irregularities prevailed, as before observed at half-flood.
A thousand grains of the water, from the bottom, yielded after
evaporation eleven grains of salt ; from the middle, nine grains,
and from the surface, twelve grains. At this time the densest
water was at the surface, and the lightest occupied the middle.
The cause of this was obvious. Extensive portions of the
sand-banks had already been left dry by the receding tide, and
various currents of water, disjoined from the main stream by
the inequalities of these banks, were now re-uniting with it,
through various channels, and disturbing the natural arrange-
ment which had prevailed during the time of flood.

Although

WITH THE SALT WATER OF THE SEA, 5it

Although the Frith of Tay is very ill calculated for experi-
ments of this kind, from the circumstances already taken no-
tice of, still the premises which we have stated seem to war-
rant the conclusion, that when the wave of the tide obstructs
the motion of a river, and causes it either to become station-
ary, or to move backwards, the effect is produced by the salt
water presenting to the current of the river an inclined plane,
the apex of which separates the layer of fresh water from
the bed of the channel, and suspends it buoyant on the sur-
face *. < 7 .

It may here be observed, that this inferior current of salt-
water, will never reach that point of the bed of the river, which
is intersected by a line drawn perpendicular to the altitude of
the wave of the tide, in the ocean, at the mouth of the river.
This point is undoubtedly the place at which the salt-water
would arrive, at every flood, were there no fresh-water current,
as has been demonstrated with regard to the waters of the
Tay, by the accurate observations of Mr James Jarprne.
But as the motion of the current of salt-water is retarded by
the opposite current of the fresh-water, and the apex of the
wedge which it forms, also washed away by the same agent,
the point which the salt-water reaches will be considerably
lower than the summit of the tide-wave with which it is con-
nected.

The surface of the higher part of the river, whose elevations
and depressions are influenced by the movements of the tide,
will necessarily attain a higher level than the summit of the
tide-wave, in consequence of the lower specific gravity of the
river-water, when compared with the denser column of sea-

water,

* T understand that my friend Mr Rosert Srevenson has made similar obser-
vations at the mouth of the Dee, near Aberdeen, and also on the Thames, and that
his conclusions and my own nearly coincide.

512 JUNCTION OF THE FRESH WATER OF RIVERS

which it counterbalances ; and this, independent of the pro-
gressive motion of the tide in the river.

If the view which we have taken of this subject, in reference
to the progress of the salt water, be considered as just, it will
enable us to explain some of the phenomena of nature, at pre-
sent rather perplexing, and may even be useful in its practical
application.

In examining the vegetable productions of the banks of ri-
vers, at their junction with the sea, we are sometimes surpri-
ed to witness the growth of plants, considered as the natural
inhabitants of the sea-shore. But our surprise will cease when
we reflect, that the sea-water proceeds farther up the river at
every flood-tide than the sensible qualities of the water at the
surface indicate ; so that the plants, which we hastily conclude
to be out of the reach of the salt-water, are still within the
sphere of its influence. Thus, at the Beach of Flisk, and even
farther up the river, the Fucus vesiculosus, (the species commone
ly cut for making kelp) not only vegetates, but in its season
appears in fructification.

But that which proves in a still more decisive manner, the
action of the inferior stratum of salt-water at the place, is the
growth of the coralline termed T'ubularia ramosa (Exx1s’s Co-
rallines, Tab. xv. fig. A.), and another of a different genus,
closely resembling the Sertularia gelatinosa of Pattas. There
are likewise some traces of Flustre.

A knowledge of the facts which we have already stated, may
be of use to those who are engaged in the erection of salt-
works at the mouths of rivers. In such situations, the open-
ings of the pipes for obtaining the salt water, should be placed
as near the bottom, or as deep in the water as possible; and
water ought only to be drawn during the height of flood-tide,
when the fresh-water is diffused over the surface.

Even

eee eee ae Se oe

WITH THE SALT WATER OF THE SEA. 513

Even to navigators, an acquaintance with this subject may
sometimes be of use. Thus, for example, when entering a
creek in an unknown coast, they may easily ascertain whether
any streams of fresh water flow into it, by examining the com-
parative density of the water taken from the surface and from
below.

These experiments appear to give countenance to the opi-
nion which supposes that the water at the surface of the sea
contains less salt than the water at the bottom. This may be
expected to take place in the neighbourhood of continents, at -
least, whatever may be the case in the open ocean. During
winter, the difference is probably very considerable, as at that
season the rivers incessantly pour vast quantities of fresh wa-
ter into this great reservoir, while but a small portion is ab-
stracted by evaporation. In the Frith of Forth, the difference
between the dense water of summer and the diluted water of
the winter season, is as eighteen to sixteen, and that even as.
_ far down as Prestonpans.

Manse oF FLIsx,
11th March 1816. }

XXIV,

os

XXIV. Memoir of the Life and Writings of the Honourable
ALEXANDER Fraser Tyrier, Lord Woodhouselee. By
the Rev. Axcurpatp Atison, LL. B. F. R. S. Lonp..
& Ep.

(Read June 3. 1816, and January 6. 18177. )

Rcrosari TyrLer was born at Edinburgh, 15th October
1747. He was the eldest son of our late venerable associate
Witiram Tyrier, Esq. of Woodhouselee, in the county of
Mid-Lothian, and of Anne Crarc, daughter of Jamzs Craic,
Esq. of Costerton, in the same county. ?

If the most important education is that which is received
beneath the paternal roof,—if it is there that the principles and
tastes of future life are chiefly formed, the education of Mr
Tyrer began under fortunate auspices. His father was a
man of high honour, of generous affections, of cultivated taste,
and of distinguished eminence in his profession. His mother
was a woman of elegant manners, of great gentleness and ten-
derness of disposition, and of still greater firmness of moral
and religious principle. And the society in which they lived
was nearly that of all those who then were distinguished in

Vou. VIII. P. I. 3T this

516 MEMOIR OF

this city, by their manners, their talents, or their accomplish-
ments. These advantages were not lost upon Mr Tyrter;
and in this domestic school he early acquired that taste in life,
or that sensibility to whatever is graceful or becoming in con-
duct or in manners, which ever afterwards distinguished him,
and which forms, perhaps, the most important advantage that
the young derive from an early acquaintance with good so-
ciety.

In the year 1755, he was sent by his father to the High
School, then under the direction of Mr Marnerson. In that
school he remained five years, distinguished to his school-fel-
lows by the gaiety and playfulness of his manners, and to his.
teachers, by his industry and ability ; and, when he left it, he
left it with the highest honours which the school ean bestow,
as Dux of the Rector’s, or highest class.

The High School, however, although then a respectable se-
minary of education, had not yet acquired the eminence which
it has since attained, by the zealous activity of the late Dr
Apam, and, more recently, by the enlightened improvements
of the present Rector, Mr Prrrans. To complete the classical
education of his son, Mr Tyrer, therefore, determined to
send him to one of the academies of England; and for this
purpose he chose the Academy at Kensington, then under the
care of Mr Expuinston, a man of learning and of worth, and
distinguished by the friendship of Dr Samvet Jounson. It
was in the year 1763, when he was fifteen years of age, that
Mr Tytier went to Kensington. He was himself at that time
conscious of the imperfection of his classical knowledge ; he felt
that he had yet much to learn, particularly in the articles of
Prosody and of Composition, and he entered the academy with
the ambition of returning an accomplished scholar. The pro-
gress of youth, and the instructions of his father, had now

awakened

ee

‘LORD WOODHOUSELEE, 517%

awakened him to a sense of the beauties of classical composi-
tion; and the names of Jounstone and Bucuanan reminded
him, that the accomplishments which he now travelled to ac-
quire, were once the produce of his own country.

With this ambition, he soon distinguished himself among
his school-fellows of the Academy. He became the favourite
pupil of Mr Exrnrysron, and received from that worthy man
all that cordial assistance and encouragement which knowledge
has so fortunate a pleasure in affording to the ardent and aspi-
ring mind of youth. A little incident, at this time, too, oc-
curred, which served to confirm Mr Tyrter in his love of
Latin poetry, and in his ambition to excel in it.

The celebrated Dr Jorrin was at that period vicar of Ken-
sington. Upon some occasion, when Mr Tyrer had particu-
larly gratified Mr Exrurnston, by a copy of Latin verses, the
good man carried them in exultation to Dr Jorrin. The ver-
ses pleased Dr Jontin so much, that he requested to be made
acquainted with the author. Mr Tyrier was accordingly in-
troduced to him. He received him with the greatest kindness,
and, after praising the composition, and encouraging his assi-
duity, he took down a copy of his own Latin poems, and re-
quested Mr Tyrer to accept of it, as a memorial of his ap-
probation and regard. This volume, with a little inscrip-
tion in the author’s handwriting, Mr Tyrier ever afterwards
preserved with veneration, and often acknowledged, that much
of his attachment to Latin verse was owing to this little inci-
dent.

It is among the most important effects of these studies in
early life, that they awaken the minds of the young to a new
sense of the beauties of Nature, and of the charms of poetical
imitation. Both these effects Mr Tyrizr seems at this period
to have experienced. It was during his residence at Kensing-

3T2 ton,

518 ' MEMOIR OF

ton, that he first began the art of drawing, and the study of
landscape-painting ; a pursuit which he continued ever after-
wards to follow, and which formed one of the most favourite
amusements of his future life. At the same time also, in his
hours of leisure, he began by himself the study of the Italian
language ; and in the early admiration of the poetry of that
country, with which his industry was then repaid, opened to
himself a field of elegant and of refined amusement, which he
never ceased to cultivate with increasing delight.

There was another acquisition which Mr Tyrier accidental-
ly made at this time, of which he always spoke with gratitude.
It was the love of the science of Natural History. When he
went to Kensington, he was particularly recommended by his
father to his early friend Dr Russet, the celebrated physician
of Aleppo, who at that time resided in the neighbourhood of
Kensington ; and with this respectable and intelligent man Mr
Tyrer used always to pass his holidays. Dr Russrri was
then engaged in the pursuits of natural history ; and seeing
the ardour of his young friend for knowledge, he made him ac-
quainted with the general principles of the science, associated
him as his companion in study, and delighted him, in their
leisure hours, by his accounts of the scenery and productions
of the East. To these studies Mr Tyrie was then alone led
by the charm which, in his eyes, they threw over Nature, in
the illustrations they every where afforded of the wisdom and
benevolence of its Author. He did not foresee that they were
afterwards to become to him the source of unfading consola-
tion, and to relieve many an oppressive hour of lassitude and
pain.

In 1765 Mr Tyrter returned to Edinburgh, after two
years passed at Kensington, with equal happiness and improve-

ment. Of these years he always spoke with pleasure, and of
Mr

LORD WOODHOUSELEE. 519

Mr Expuinston with the most grateful and affectionate regard.
He continued ever afterwards occasionally to correspond with
him ; and so little did the lapse of time, or the business of ma-
ture life, diminish the remembrance of early obligations, that
when Mr Expurnsron died, he had the satisfaction of associa-
ting himself, with his respectable widow, in erecting, in the
church-yard of Battersea, a monument to his memory.

In the close of the year 1765, Mr Tyruer entered the Uni-
versity of Edinburgh, and upon a new field of knowledge and
of study.

The profession to which his own disposition, and the wishes
of his father inclined him, was that of the Law; the profes-

sion, of all others connected with literature, most.attractive to .
the ambition of a young man, both by the variety of powers
which it demands, and the importance of the distinctions to
which it leads. It was to this end, accordingly, that his stu-
dies were now chiefly directed ; and although he attended the
lectures of Mr Russet upon Natural Philosophy, and of Dr
Brack upon Chemistry, yet he seems to have limited himself
to a general knowledge upon the subject. of physical science,
and to have reserved the vigour of his attention for those clas-
ses that more immediately related to his future profession.
While he was pursuing, therefore, the study of Civil Law, un-
der the tuition of Dr Dicx, and afterwards of Municipal Law,
under that of Mr Wanxzack, he followed with interest the use-
ful and perspicuous prelections of Dr Srevenson in the science
of Logic: he improved his taste by the celebrated lectures
which Dr Buarr was then delivering upon the subject of Rhe-
toric and Belles Lettres ; and he listened with ardour to that
memorable course of Mixa Science, in which Dr Fereuson il-
Justrated, with congenial power, the various systems of ancient

philosophy,.

520 ‘MEMOIR OF

philosophy, and occasionally exhibited all the splendors of an-
cient eloquence.

Of the progress or success of Mr Tyrxen’s studies during
these years, no record, indeed, remains in the annals of the

University. It has been the practice, and perhaps the wisdom:

of the Professors of that distinguished Seminary, to seek more
to gratify the desire of knowledge in the young, by the instruc-
tion they convey, than to stimulate it by the distinctions they
confer ; and to look for their reward rather in the future emi-
nence of those they instruct, than in the display of early and
premature exertion. Of the dispositions or attainments of the
young, however, there is, at this age, one unfading proof to be
found, in the character of the friends and associates whom they
select. The circumstances of the times, and the celebrity of
the Professors, had at this period excited in the young men of
the University, an unusual spirit of literary ambition, and many
of those who have now arisen to the highest distinctions in
their country, were at this time laying the foundations of the
eminence to which they have attained. It was in this class
that Mr Tyrier sought for friends, and it was in this class he
found them. The vivacity of his temper, the variety of his at-
tainments, and the high spirit of honour which distinguished
even his earliest years, rendered him acceptable to all the
young and spirited of his own age; while his zeal for know-
ledge, and his ambition of distinction, conciliated the regard of
those who were older. It was in these years, accordingly, that
the great friendships of his life were formed ; and it was his
peculiar happiness, that among those to whom the affections
of his youth were given, the course ‘of his mature life was
passed, and its final period was closed. The list is an ample
one, and will not be heard in this Society without emotion ;
for it contains the names of Henry Mackenziz, of ALEXANDER

~~ ABERCROMBIE

'

LORD WOODHOUSELEE. 525

Apercromere (late Lord Axercromste), of Writram Crarc
(late Lord Craic), of Arran Maconocute (late Lord Mea-
powzank), of Wittram Apa (now Lord Chief-Commissioner),
of Rosert Lasron, of ANprew Dawzet, of Wittram Rosgert-
son (now Lord Rozertson), of Joun Prayrarr, of Dr Gre-
cory, and of Duéatp Srewart,—men, whom in this place it
would ill become me to insult with praise, but from whose
friendship, I may be permitted to say, there is no name so il-
lustrious that would not derive distinction.

If the seasons of academical ‘study were thus happily and
usefully employed by Mr Tyrter, the seasons of the summer
vacation were not less so. Upon these occasions, he retired
to Woodhouselee, the beautiful seat of his father, near Edin-
burgh, a scene endeared to him by the remembrances of in-
fancy,—by all the ties of domestic affection,—by the improve-
ments which his father was then annually adding to it,—and,
perhaps, by those anticipations of greater embellishment which
it was afterwards to receive from his own hands. Amid the
solitude and quiet of this romantic residence, and at a distance
from the prescribed routine of academical labour, he felt all the:
happiness that arises from the freedom of study, and was at
liberty to follow out, without interruption, those literary pur-
suits to which inclination and taste most strongly inclined him.
The character of his age, and of his mind, led him naturally to.
those compositions which, as addressed to: the imagination and.
the heart, constitute the polite literature of every country.
His knowledge, both of the ancient and the modern languages,,
enabled him to indulge this desire; and in the course ‘of

* successive summers, he seems to have formed and to have exe-
cuted,-with this view, a plan both of comprehensive and of

systematic study.

$22 - MEMOIR or

He began with the great writers of antiquity—the Poets,
the Orators, and the Historians of Greece and Rome, to whose
works he now returned with that increase of knowledge, and
that improvement of taste, which enabled him more fully
to seize and to appretiate their various excellence. He next
resumed, (though with more enlightened views), the study of
Italian literature, and perused with new admiration the writers
of that brilliant period which succeeded the revival of letters
in Europe, and who, though formed, in the great principles of
composition, upon the models of classic taste, have yet added
to them all the splendid courtesy of feudal manners, and all
the romantic interest of chivalrous adventure. After the ex-
tinction, or (as I trust) only the slumber of Italian genius, he
followed the progress of taste into France, and pursued the
singular history of composition in that country, from the pe-
riod that the genius of CornerILix first gave to its imperfect
language the dignity of poetry, to the time that the eloquence
of Feneton, of Burron, and of Rousseau, rose above the level
of its poetic diction, and gave to prose composition all the
powers and all the pathos of poetry.

The study of foreign literature led Mr Tyrxer naturally to
that of his own country, and, in comparing the great writers of
England with those of the different nations of the Continent,
he was enabled to form a more accurate estimate, both of the
_ extent of English genius, and the powers of the English lan-
guage. While engaged in this pursuit, his curiosity was led
into a field at that time little cultivated in this country, I mean
to the study of the ancient writers of England, those original mas-
ters of composition, in whose writings the genius of the people ‘
and of the language is most strongly displayed, and who con-
ducted him (in the language of Spenser) to “ the pure well of
“ English undefiled.” The pursuit not only rewarded him at

the

LORD WOODHOUSELEE. 528

the time, but tended to form his taste in future days; and he
was among the first literary men of this country, who felt the
beauty of our language in its first stage of improvement, and
foresaw the advantages that the study of our earlier writers
would give to modern composition, by introducing greater
unity of character, a purer analogy of construction, and the
peculiar energy that arises from idiomatic expression.

The same taste which guided the studies of Mr Tyrer at
this, period, directed also his amusements. The art of Draw-
ing, which he had at first begun to practise at Kensington, he
now resumed with ardor, amid the beautiful scenery he inha-
bited. The love of Music, which was hereditary in his family,
had been cultivated by the example, and under the instruc-
tions of his father, and he willingly became a performer, not
only to indulge his own taste, but that he might add his assist-
ance to the little family concerts with which that excellent
man loved always to close his active day. But the amusement
in which at this period Mr Tyter peculiarly delighted, was that
of making excursions to visit the remarkable scenery, either of
England,.or of his own country. He had an early love of the
great and beautiful in Nature; and his sensibility in this respect
had been increased by his study of landscape painting. But his
taste was not of that servile kind, which looks only to the art
of imitation: and he felt that there were many other sources
of beauty in the scenery of Nature than the painter can em-
ploy. His mind was open, not only to all those moral expres-
sions which form what has been called the poetry of Nature,
but to all those local and accidental expressions which it re-
ceives from the events of time; and he loved to mingle in such
scenes, with the sensibilities of taste, the associations of poeti-
cal description, and the memory of historical events. In this

manner, Mr Tyrrzr used always to pass some parts of the
Vou. VIII. P. IT. 3U summer

524 MEMOIR OF

summer or autumnal months ; and, in the course of a few years,
there were few scenes, either in England or in Scotland, which
he had not visited, that were distinguished, either by natural
beauty,—by poetical celebration,—by the residence of eminent
men,—or by the occurrence of memorable transactions. In
such employments, to him (as to all who are capable of it)
there was something more than amusement; and he never
returned from them, without feeling his taste improved, his ar-
dour in study animated by the memories of illustrious men,
and his love of his country increased, both by the monuments
of its former glory, and the appearances of its progressive
prosperity.

In the year 1770, Mr “Tetcacing was called to the Bar; and in
the spring of the succeeding year, he accompanied his friend
and relation Mr Kerr of Blackshiels on a tour to Paris, from
which they returned by Flanders and Holland.

The year 1776 was marked by the most important as well
as the most fortunate event of his life, by his marriage to Miss
Anne Fraser, eldest daughter of Witt1am Fraser, Esq. of
Balnain,—an union which Fan long been the object of his se-
cret wishes,—which now stata licked all the hopes he had
formed of domestic happiness,—and which, after the long pe-
riod of thirty-six years, unclouded almost by misfortune or dis-
tress, closed at Jast in more grateful and profound affection
than it at first began.

At this period, when the business and the duties of life were
opening fully upon him, Mr Tyrier seems to have made a
very deliberate estimate of the happiness that was suited to his
character, and to have marked out to hiniself, with a very firm
hand, the course he was afterwards to pursue. His profession
opened the road both to professional fame, and to civil distine-
tion, and the circumstances of the times were of a kind to ani-

mate

LORD WOODHOUSELEE. 525

mate all his ambition of literary distinction. The period to
which I allude, was perhaps, indeed, the most remarkable
that has occurred in the literary history of Scotland. The
causes which, since the era of the Union, had tended to re-
press the spirit of literature in this country, had now ceased to
operate: the great field of England was now opening to the
ambition of the learned; and the ardour with which they ad-
vanced into it, instead of being chilled by national prejudice
or jealousy, was hailed by the applause of that generous people.
The fame of Mr Hume was now at its summit of celebrity.
After the honours with which the Histories of Mary and
Charles V. were crowned, Dr Rozertson was laying the foun-
dation of new claims to historical reputation ; and in the soli-
tude of his native village, Mr Smrru was preparing that illus-
trious work which was afterwards to direct the laws, and to
regulate the welfare of nations. The different Universities of
the country were vying with each other in the ardour of scien-
tific pursuit, and in the dissemination of useful knowledge ;
and from them there were annually advancing into life, some
of those men who have since supported or extended the repu-
tation of their country. The profession of law partook in the
general spirit of improvement: the pleadings of the Bar began
to display a more cultivated taste, and the decisions of the
Bench to be directed by a more enlightened philosophy. The
eloquence of Mr Locxuarr was still occasionally heard ; and
Mr Erskine was beginning that brilliant career which so late-
ly only has been closed. Lord Hares was carrying into the
obscurity of our antiquities the torch of severe but sagacious
criticism ; and Lord Kames was throwing over every subject
almost of science or of literature, the lights of his own original
and comprehensive genius.

3U 2 These

526 MEMOIR OF

These were circumstances sufficient to excite and to justify
ambition ; but although Mr Tyrrer was ambitious, it was not
so much of fame he was ambitious, as of usefulness. The mo-
desty, as well as the benevolence of bis nature, disqualified him
for those adventurous speculations, in which nothing but perso-
nal celebrity is attained; and in looking at the literary scene
before him, the path that invited him, was not that which rises
amid dangers and difficulties into solitary eminence, but that
which follows out its humbler and happier way amid the duties
and charities of social life. In all his ambition, too, there was
(if I may use the expression) something always domestic. The
honours to which he aspired were those which he could share
with those he loved, and the “ eyes” in which he wished fo
read his history, were not so much the eyes of the world, as
those of his family and friends. It was with this moral and
chastised taste that he looked even to the honours of his pro-
fession: And when he recollected the brightest distinction it
ever received, it was not Cicero in the Forum or in the Senate
House, that was so much the object of his admiration, as
Cicero at his Formian or his Tusculan Villa, amid the enjoy-
ments of domestic friendship, and the delights of philosophic
study.
With these dispositions, Mr TyrLzr soon found, that the
share of business which a young man can acquire at the Bar,
was insufficient to employ the activity of his mind, and that
the merely occasional attention which particular cases requi-
red, was at variance with those habits of continued study in
which he was accustomed to be employed. To consider law
as a science was more congenial to his mind, than to consider
it only as a profession ; and he became desirous, therefore, of
engaging in some continued work, where (like some eminent
men before him) he might entitle himself to the honours of

his

LORD WOODHOUSELEE. 627

his profession, rather by the labour of solitary study than by
the celebrity of actual practice. While he was forming this
resolution, the advice of his patron and friend Lord Kames,
not only encouraged him to execute it, but suggested to him
also a subject in which it might usefully he executed. As this
incident gave origin to the first work which Mr Tyrtrr pu-
blished, and as it is descriptive of the benevolent attention of
that distinguished man to his younger friends, I am happy to
be able to relate it, in Mr Tyrier’s own words, from a little
manuscript account of the principal events of his life, which
he has left for the instruction of his family.
——< The first time (says he) I became intimately acquaint-
“ ed with Lord Kames, was, I think, in autumn 1767, when
“he asked my father and me to accompany him on the South-
“ern Circuit. We passed a few days with him at his estate of
“* Kames, and thence travelled to Jedburgh and Dumfries.
“ From that time I had the satisfaction of perceiving that. I
“had some share in his good opinion, of which he gave me
“many proofs. While prosecuting my studies in the law, I
** was wont frequently to resort to him for his advice, and in
“the vacations I made many excursions to Blair-Drummond,
“ where I staid for ten days or a fortnight at a time, and par-
~“ took in all his occupations either of study or of amusement.
“ Having read to him alittle literary Dialogue which I had’
“composed, with which he was pleased, he gave me his. ad-
~ vice, to fill up my intervals of leisure by composing a set of
“ Literary Essays: In consequence of which, I wrote a few de-
“ tached sketches, which I shewed him from time to time. | It
was upon one of these visits to Blair-Drummond, about three
“ years after I had put on the Gown, that, in talking of some
“of his Law Works, he asked me if ever I had attempted to
“ write any thing in the way of my profession. I told him
* that

§28 MEMOIR OF

“ that I had not, but that I was at that time meditating some-
“ thing of that kind. He then proposed to me to write a Sup-
plemental Volume to his Dictionary of Decisions, bringing
* down that Work to the present time. I told him, that the
“‘ boldness of the undertaking terrified me ; but that the good
“ opinion he had shewn of me by making such a proposal, was
“ certainly a strong inducement to me to make the attempt.
“ T took, however, some time to deliberate upon it; and ha-
“ ving at length resolved to undertake the work, I went out
“ again to Blair-Drummond, to inform myself of the method
“ he had followed in abridging and arranging the cases. These
“ he communicated to me, and I set to work under his eye.
“ The simple abbreviation of the printed cases occupied me
“ above four years, and during all that time I read over occa-
“ sionally to Lord Kames, the sheets of my abstracts, on which
“ he gave me his notes and emendations. The arrangement
“ of the cases gave me another year’s employment ; and while
“ this was going on, I shewed the sheets, from time to time, to
«“ Lord Kames, a great part of them to Mr Inay Campsexz,
“ as also to the Lord President Dunpas, to all of whom I was
“ much indebted. When the Work was completed and print-
«« ed, I was much gratified to find that Lord Kags was plea-
“*sed with it. Some passages in the Preface, apologizing for
* defects, he desired that I would strike out. ‘ The Work,
“ (said he,) does you honour; and a man ought not too much to '
“ yndervalue his labour, or depreciate his own abilities.” This
volume of the Dictionary of Decisions was published in folio,
in 1778; and of the character and value of the work, no other
testimony is necessary after the sanction of the great Lawyers
that have been mentioned.
_ Mr Tyrter had now avowedly dedicated his life to the pur-
suits of Literature, and his friends became anxious to see him
placed

a
.

LORD WOODHOUSELEE. 529

placed in some one of those public literary stations, where his
talents and his industry might be more conspicuously displayed
than in the retirement of private study. An opening of this
kind soon occurred, which Mr Tytxer willingly embraced. The
late Joun Prinexe, Esq. had been recently appointed to the
Professorship of Universal History and Roman Antiquities in
the University of Edinburgh ; but finding the discharge of the
duties of it incompatible with his other employments, had ex~-
pressed his inclination to resign it. The Class, (I believe,) in.
its original institution, in this and in other Universities of Scot-
land, had been intended as subsidiary to the study of the Civil
Law. It had been taught always by Members of the Faculty
of Advocates, and attended by students of that description :
And it had, therefore, that degree of relation to Mr Tyt1izn’s
own profession, that forfeited none of the hopes or expecta-
tions he might form of its future distinctions. An arrange-
ment was soon made with Mr Prinexe. In 1780, Mr Tyrrer
was appointed Conjunct Professor, and in 1786, sole Professor:
of Universal History.

From that period until the year 1800, Mr Tyr1ter devoted
his life almost exclusively to the duties of his Professorship ;
and ten years of assiduous study were employed in the com-
position and improvement of the Course of Lectures which he
annually read in the University.

- Of the character and value of that Course of Lectures I
should have felt it a duty to have attempted some slight de-
scription, if I were not prevented by the presence of many, to
whom every attempt of this kind would be superfluous, and by
the recollection, that while they remain unpublished, they
cannot be the objects of public criticism. I may be permit-
ted, however, to offer to the Society a few observations upon
the views with which Mr TytLex entered upon his Professor-

ship,

530 MEMOIR OF

ship, and upon the plan he pursued in the conduct of his Lec-
tures.

The Class had hitherto been taught chiefly in relation to the
Science of Law, to which it was considered as subsidiary. It
was not so much Universal History that was the subject of
prelection, as the History of Rome; and the views that were
exhibited of Roman Antiquities, were chiefly those that were
illustrative of the principles or progress of the Civil Law. Mr
Tyruer felt that it became him to take a more comprehensive
view of the subject ; to aim at higher utilities than those of
a single profession ; to adapt his Lectures to the more libe-
ral opinions which had arisen with regard to education, and the
increasing celebrity of the University where they were to be
delivered ; and in the course of them, (as he has himself ex-
pressed it,) to exhibit a progressive view of the state of mankind
from the earliest ages, of which we have any account,—to deline-
ate the origin of states and empires,—the great outlines of their
history,—the revolutions which they have undergone,—and the
causes which have contributed to their rise and grandeur, or ope-
rated to their decline and extinction.

In the execution of a design so extensive, Mr Tyrxer’s at-
tention was first directed to the choice of a Plan, or to the
formation of a system of arrangement, by which he might be
able to give some degree of unity and consistence to the great
mass of materials that were before him. In examining the
methods in which Academical Lectures on this subject had hi-
therto been conducted, either in this country or on the Conti-
nent, he perceived that there were two different systems which
had chiefly been followed, and which may, perhaps, not impro-
perly be styled the Narrative, and the Didactic Systems. In
the first, the principle of arrangement was simply that of Chro-
nology : the only order observed was the order of time, and

the

LORD WOODHOUSELEE. 531

the only object.of the teacher was to convey to the student
the knowledge of the succession of historical facts. In the
second, the principle of chronological arrangement was :alto-
gether disregarded: the events of history were considered not
as a branch of knowledge in themselves, but as a ground. work
for the conclusions of science; and the great object of the
teacher was to convey to the students the knowledge of
the general puncinles of public law and of political philose- .
phy. ,
In neither of Saniss systems did Mr Tyrrrr find the utilities

which it was his ambition to derive from the subject of his lec-
tures. The first appeared to him only a barren detail of chrono-
logical events, in which nothing more was conveyed than the
mere knowledge of the succession of these events ; and all that
is included under the name of the Philosophy of Fass was 11e-
cessarily omitted. In the second, he feared that too wide a field
was opened to the ambitious speculations of the teacher, and
that while the attention of the student was liable to be occu-
pied by hasty or by unfounded theories, the interest of his-
torical narration was necessarily lost, and all the moral instruc-
tions of history neglected.

» The system which Mr Tyrter finally ncléipted for his own
course of lectures, was one which combined the advantages
of both these systems, and was very happily adapted, both to
maintain the interest and to consult the instruction of the stu-
dent. In surveying with an attentive eye, the ancient history
of the world, he observed, (to use his own words,) that it was
distinguished, in every age, by one prominent feature; Thai
one nation or empire was successively predominant, to whom all
the rest bore as it were an under-part, and to whose history, we
Jind that the principal events in the annals of other nations may
be referred from some natural connection. In this remarkable

Vox, VIII. P. II. 3X feature

532 MEMOIR OF

feature Mr Tyrter saw that a principle of natural arrangement
was afforded him, which might give to his course a sufficient
degree of unity and order ; aad which, while it preserved to
the student the interest of historical narration, gave to the
teacher the opportunity of exhibiting those general views of
the progress of the human race, which form the most import-
ant instruction we can derive from its history.

It was on this principle that his course of Ancient History
was conducted. After some general prospects of what is known
of the Assyrian and Egyptian Empires, he began with the bril-
liant and interesting subject of Greece. He treated at length,
the events of its civil and political history, and in conduct-
ing his marr ative, brought occasionally into view the situation
oft the nations by vibes it was surrounded. He then exami-
ned the nature of the various governments which distinguish-
ed it;—the different political institutions which they had adopt-
ed,—the character of their military establishments,—their
principles of colonization, and of internal regulation: And
when time had conducted him to the ssielanieioly period of the
extinction of their independence, he took a retrospective view
of its literary history,—of the state of its attainments in arts
and science, and, above all, of the nature and causes of that
unequalled excellence which it attained in all the arts of
taste.

The next great subject which presented itself was the his-
tory of Roi and in the views he took of this magnificent.
portion of his course, he followed the same arrangement, and
employed the same method of instruction. After recounting
its obscure origin and infant institutions,—after tracing the
progress of its political constitution, until it terminated in that.
ilustrious Republic, which, though so long extinct, still reigns,
as by some magic spell, over the minds and imaginations of

mankind,

LORD WOODHOUSELEE. 533
mankind,—he followed the progress of its arms through a world
hitherto unknown 5 and thus gradually. introducing to the ob-
servation of his students, those various nations of the North,
that were destined i in future years to overturn this mi ighty fa-
bric,. he made the easiest, but the most fortunate, transition
to the history of Modern Europe, and: to the examination of
the causes that produced the fall of Rome. . At this. eventful
period, he again availed himself of the pause which history af-
forded him, to take a retrospectiy e view of this great people,
—to consider. their attainments in arts and arms,—to compare
their. progress . in science and in literature with that of the
mighty. people. that had preceded them,—and to indulge him-
self in that illustration, of the excellence of their greater wri-
ters, which he was so well qualified , to give, and which, far bet-
ter than mere critical examination was wert to excite the admi-
ration, and t to form the taste, of the young who heard] him. |
The history | of Modern Europe : affor ded not to Mr‘ Tyrie
the same fortunate principle of arrangement which he had
found i in. the Ancient ; But another principle of connection
presented . itself, of which he willingly availed himself. To
the historian ‘of Modern Europe, the natural place of observa-
tion is his own countr y. It isthe point . of view to which all
his interests 1 most obviously conduct him, and from which all
the events ¢ a the surrounding world f fall into somewhat of SYS-
tematic order and harmonious d distance. ‘Tt was on this prin-
ciple, therefore, that ; Mr Tyner conducted ‘his views | of mo-
dern history. Considering ‘the history « of. their « own country
as the, subject most important in the instruction o ‘of his stu-
dents, he began by the ‘narration. ¢ of. the great e events of its ci-
vil and military. story : He traced the : successive steps. of its
progress i in ‘industry, i in legislation, in opulence, and i in refine-
ment ; and | unfolded. y with, care the gradual 1 rise ‘of its political
3X 2 Coasieation,

534 MEMOIR OY

constitution, until it terminated in the memorable era of the
Revolution. From this central point of observation, he took
occasion, at different times, to direct the attention of his stu-
dents to the contemporary history of mankind,—to mark to
them the successive changes that were occurring upon the Con-
tinent of Europe —to introduce to them those new empires
which at one period the frenzy of fanaticism, and at another the
avarice of commerce, had revealed to the European eye,—and
to awaken their attention to the mighty consequences which
the establishment of Christianity, the invention of printing,
the discovery of the New World, and the spirit of the Refor-
mation, have had upon the general character and manners and
happiness of modern times. With these great subjects he
gladly at times interwove the history of literature and sci-
ence ; and while his attention was chiefly directed to the pro-
gress of British literature, he led the observation of his stu-
debts to the contemporary history of learning upon the Eu-
ropean Continent, and to the examination of those general
causes which had influenced the successive steps of its pro-
gress, from the time of the revival of letters to the brilliant
period when his lectures closed.

The success of this course of lectures was sufficient, (as Mr
Tyrxer has said,) “ to compensate the labours of the author.”
They came to form an important part in the system of general
education ; and he soon numbered among his students, not only
those who were destined to the profession of the law, but the
young of every different description, whose education was con-
ducted upon liberal and philosophical principles. The little vo-
lume which he published in 1782, under the title of Outlines of a
Course of Lectures, for the assistance of his students, became
so popular, that he found himself called upon to present it to
the world, in a larger form, under the title of Elements of Ge-

neral

LORD WOODHOUSELEE. 535

neral History, in two volumes. This work has since pass-
ed through four editions, and has been found so useful‘ by
those engaged either in the business of private or public edu-
cation, as affording a concise and luminous arrangement of
historical events, that it is now used as a text-book in some
of the principal seminaries of education in England, and has
Become (as I understand) the ground-work of historical study
in some of the Universities of America.—Of the lectures them-
selves, while they remain unpublished, it would be preposter-
ous to offer any opinion: yet, when they are given to the
world, I shall be much deceived, if they are-not found to fill
up an important desideratum in English literature,—to afford.
to the minds of the young more pleasing and more enlighten-
ed views of the history of Man, and the progress of the Hu-
man Race, than any other similar work in our language pre-
sents them, and to accomplish the generous ambition of their
author, in rendering the study of history subservient to the great
end of all education, that of forming good men and good citi-
zens. .

‘The labours im which Mr Tyrer was thus employed, were:
sufficient to occupy, but not to engross, his attention. Hecon-
tinued assiduously his practice at the Bar; and he followed,
with the interest of a man of letters, the progress of Science
- and Philosophy around him: ~The reputation which his taste
and talents had now acquired, created many appeals to him for
literary advice or assistance, and to him every labour was wel-.
come, in which he could serve the cause either of literature or:
of friendship.

In 1778, when Dr Grecory was publishing an edition of the:
Works of his Father, Dr Joun. Grecory, he solicited Mr Tyt-
ter to prefix to it a short account of his life and’ writings.
It was a task which Mr Tyrer willingly undertook, from his

early:

536 - . MEMOIR OF

early acquaintance with that eminent and amiable man, and
he executed it with the simplicity almost of filial reverence and
affection.

The year 1779 was distinguished in this country by the ap-
pearance of the celebrated periodical paper, The Mirror. :Ot
the progress of a work which, both in its design and execution,
did so much honour to Scotland, Mr Tyrier could not be an
indifferent spectator. Although not properly a member of the
Society, he was yet the friend of all who were known to be
members of it. To the beauty and excellence of the serious
papers in this work, Mr Tyrzer felt that nothing could be
added ; but it seemed to him that something was wanting up-
on the side of levity and gaiety ; ; not only for the purpose of
temporary popularity, but to give to the serious papers them-
selves their proper importance and relief. With this view, he
contributed tothe Mirror the papers, Nos. 17.37. 59. and 79. ;
and in 1785, to the Lounger, the papers, No. Tai 24. 44, G7.
70. 79.

Of these papers the original manuscript happens still to re-
in, fetta Mr Tinos was accustomed ta; pass his most ‘vacant
hours. The manuscript occupies the blank Jeaves of some
-sketch-books with which Mr Tyrer always, travelled, for the
‘purpose of ,landscape-drawing, and was written at inns, in the
evenings after the journeys of. the day ,were.done. Tt was in
this manner,that.the chearful activity of his mind found em-
ployment and amusement every where ; and that the hours
which most men pass in indolence or fretfulness,. were passed
happily by him, in the offices of friendship, or in the enjoyments
_of elegant composition,

On the institution of the Royal Society in the year 1783,
Mr Tyrer was,one of its constituent members, and was un-

animously

LORD WOODHOUSELEE. 587

animously élected one of the Secretaries of the Literary Classy
—an office which he continued to fill with zeal for many
years ; and in the execution of which he drew up that “ Account
“ of its Origin and History,” which is prefixed to the Ist vo-
lume of its Transactions.

In 1788, he contributed to the Royal. Society a biographical
Memoir of the Tate Roser Dundas of Arniston, Lord Presi=
dent of the Court of Session,—a paper valle: not only for
the just and vigorous delineation which it gives of the charac=
ter of that eminent Judge, but for the interesting account it
pis some of the earlier branches of a family, so long and

so honourably distinguished in the legal annals of Scotland.

In 1789, Mr Tyrirr read a paper to the Royal Society up-
on the Vitrified Forts in the Highlands of Scotland. Of these
singular antiquities, the prevailing theory had been, that the
vferiremttaet was produced i in the process of their erection, and
that it was the substitute of a rude age forcement. The theory
which Mr Tyrier suggested was Hie aVEHSdemr ths | ;—that the
vitrification was the result, —not of their erection, but of their:
destruction,—and that it was produced by the efforts of ene-
mies in attempting this destruction by fire. The theory is cer-
tainly not without some appearances of probability : it assimi-
lates sufficiently with the period of society to which such build-.
ings undoubtedly refer; and Mr Tyrier was able to support
it with learning and ingenuity. Of the impression it made at
ihe time upon ‘the Society, I am happy to be able to refer to:
an evidence of no little weight, in a letter from our late illus-
trious associate Mi Smrru to Mr Tytier upon the subject

and, althougl 1 the letter is very short, I persuadé myself that it
will not be unacceptable to. the Society, both because there
are unhappily very few letters of this. great man remaining,

and becaiise it involves also. the memor 'y of some other men,
, whose:

588 _. MEMOIR OF

whose names can never be listened to in this place without
emotion :

Dear Sir,

“ T have read over your paper with the greatest pleasure.
The composition is what it ought to be, simple, elegant, and
perfectly perspicuous, and will be avery great ornament to our
Memoirs. Some of my chemical friends, however, are of opi-
nion, that the degree of vitrification which takes place in the
specimens of these forts, is too great to be the effect of any ac-
cidental fire, such as you suppose, and could be produced only
by a great accumulation of wood, heaped upon the wall after
it was built. This is a subject of which Iam ignorant. You
had convinced me, who fancied that this imperfect vitrification
was more likely to be the effect of accident than of knowledge.
The friends I mean, are Dr Brack and Dr Hurron, who in
every other respect entertain the same high opinion of your

composition which Ido. You had better converse with them :
you may convince them, or they may convince you; and even
though neither of these two events should happen, the offence,
I apprehend, will not be great, either to them or to you. I
have the honour to be, Me
. “ Apam Smit.”

In the year 1790, Mr Tyrer read in the Society those pa-
pers on Translation, which they who heard them will remem-
ber to have been listened to with so much pleasure, and which
he soon after published without his name, and under the mo-
dest title of an Essay on the Principles of Translation. The
work was scarcely published, when it occasioned a correspon-
dence with the late learned and ingenious Dr Campsext, Prin-

cipal

LORD WOODHOUSELEE. 539

cipal of Marischal College, Aberdeen, from which, however
painful at first, Mr Tyrier might easily have foretold its fu-
ture fortune in the literary world. Dr Campzeti had, some
time previous to this, published his Translation of the Gospels,
to which he had prefixed, in a preliminary dissertation, some
very acute and ingenious observations, upon the principles of
translation. Upon the publication of Mr Tytier’s anonymous
work, he immediately procured it, and was so much struck with
the coincidence of their views upon the subject, that he wrote to
his printer Mr Creecu, to know who was the author; and
while he acknowledged himself “ to have been flattered not a
“ little to think, that he had in these points the concurrence in judg-
“ ment of a writer so ingenious,’ he expressed at the same time
some suspicion, that the author might have borrowed from his
Dissertation, without acknowledging the obligation. Mr Crrecn,
with great propriety, communicated the letter to Mr Tyter;
and he instantly wrote to Dr Campsex, acknowledging himself
to be the author, but assuring him, that the coincidence of sen-
timent was purely accidental, and that the name of Dr Camp-
BELL’s work had never reached him until his own had been
composed. “ The coincidence of our general principles, (says
“ Mr Tyrer), is indeed a thing flattering to myself; but I can-
“ not consider it as a thing at all extraordinary. There seems
“ to me no wonder, that two persons, moderately conversant in
“ critical occupations, (I am far from thinking equally so ), sitting
“ down professedly to investigate the principles of this art, should
“* hit upon the same principles, when in fact there are none other
“© to hit upon, and the truth of these is acknowledged at their first
“* enunciation. In my opinion, there would, on the contrary, be just
“ matter of wonder if they did not hit upon them. But in truth,
“ (concludes Mr Tyt Er), the merit of this little essay, (if it has
“ any ),does not, in my opinion, lie in these particulars. It lies in the

_ Vou. VIL P. IE “i “ establishment

540 MEMOIR OF

establishnient of those various subordinate rules and precepts,which
apply to the nicer parts and difficulties of the art of translation ;
in deducing those rules and precepts which carry not their own
authority in gremio, from the general principles which are of
acknowledged truth, and in proving and illustrating them by
evamples. How far you may have anticipated me even in this
respect, I cannot say, until I have perused your Dissertations.
They appear to contain a rich mine of philological and critical
learning ; and I am confident, that if my book comes to a se-
cond edition, I may be able to profit much by your remarks. In
that case, f shall most cordially, and with the highest pleasure,
acknowledge my obligations.”

To those that are acquainted with the character of Dr Camp-

BELL, it will be unnecessary to add, that he received Mr Tyr-
Ler’s explanation with the most candid and polite liberality.

s
.

«

o

2
r

The lelier you favoured me with, (says he), made me both

ashamed and vexed, that F should have been so rash as to ex-
press myself to Mr Creecu in a manner which could give a
moment's uneasiness to a man of merit, especially one whom I

consider myself as having the honour to call a friend. When

I wrote that letter, I neither knew nor suspected who the au-
thor of the Essay was. Had I known what I now know, the
name of the author alone would have convinced me that the co-
incidence was merely accidental.—Your arguments are good,
but I was sorry you had recourse to them; sensible as I am,
that if your declaration had not been sufficient to satisfy me, I
did not deserve to be satisfied. Mathematical demonstration,

- were you to attempt it, would not give me stronger conviction

than I already have, that what you say is the truth. But to
have done with the disagreeable part of this mistake, (he con-
cludes), J cannot avoid mentioning one circumstance in this in-
cident, which to me is always extremely agrecable, the evidence

© which

LORD WOODIIOUSELEE. 54]

“ which it gives of a concurrence in sentiment upon critical sub-
Re ects with persons of distinguished ingenuity and erudition.
“ Such a discovery makes a man more confident in the justness of
“ his own sentiments. I have only to add, that your illustrations

“ of the general si and your examples fr om the ancients,
“ please me exceedingly.”

The opinion of Dr Campsett was very soon justified by the
voice of the literary world ; and 1 believe that there is no work
of literary criticism which this country has produced, that so
soon attained celebrity in England, as the Essay on Translation.
The different reviewers of the day, contended with each other in
the earliness of their notice, and in the liberality of their praise.
The most celebrated scholars of England, Dr Mari«nam, Arch-
bishop of York, Dr Dovcxas, Bishop of Salisbury, Dr Percy,
Bishop of Dromore, Dr Vincent, of Westminster, and Dr Wat-
son of Winchester Schools, wrote to the author in terms of high
approbation. “ Were I not afraid,” says Mr Murpny, the well-
known translator of Tacitus, in a letter to the author, “ of be-
“ ing thought a dealer in compliment, I should say, that I esteem
“ it the best performance I have ever seen on the subject. In-
genious hints, and cursory remarks, are to be found in many
“ authors, ancient and modern; but they remained scattered, and
“ nothing like a regular system has been formed until now.” And
Mr Cumpertanp, the extent of whose learning, and the fertili-
ty of whose genius gave so much value to his opinion, was so
much delighted with the work, and so grateful for the just
praise which Mr Tytter had bestowed upon his admirable
translations from the fragments of Greek comedy, that he
wrote to his friend Sir Wittiam Forsrs, to beg of him to pro-
cure Mr Tytxer’s permission to dedicate to him a translation
of The Clouds of AxisrorHanes, which he was then preparing,
and which the praise of so distinguished a critic had encouraged

3Y2 him

542 MEMOIR OF

him at first to undertake. To the opinion of these eminent
men, it may be supposed I very willingly subscribe; yet, I
must add, that the work has always appeared to me as entitled
even to a higher praise. In its plan, indeed, it appears to re-
late only to the principles of translation ; but in its execution,
it necessarily involves the principles of composition in gene-
ral; and in the nature and variety of the examples he adduces,
and the acuteness and delicacy of the criticism he employs, Mr
Tyrer seems. to me to have made use of one of the happiest
methods to lead the minds of his readers to a sense of those
fine and evanescent beauties in composition, which abstract
language can so imperfectly express, and which affords. the
best preparation, not only for the task of translation, but for
the higher purpose of original composition.

The Essay on the Principles of Translation has now passed
through five editions, in each of which the author has been
anxious to repay the approbation of the public, by the addi-
tions he has made; and after the experience of fifteen years, it
may now be considered as one of the standard works of =
lish criticism.

While Mr Tyrrer was thus actively and usefully Sinjohayel,
the Government of Scotland began to consider him as one who
was fitted to share in its administration, and Lord Mezviixe
thought himself now entitled, by the character which Mr Tyt-
Ler had established, to testify to the public the sentiments of
his private friendship. His practice at the Bar, though not
extensive, had been respectable, and, in the conduct of it, he
had shewn sufficiently the talents he possessed for business.
His honour was high,—his integrity acknowledged,—and_his
manners amiable and conciliating. His political opinions were
those of hereditary loyalty ; and in the acceptance therefore of
office, he had none of those sacrifices of principle to make, by

which

LORD WOODHOUSELEE. 543

which the course of political. ambition has been sometimes de-
graded. In the year 1790, he was appointed een Sete
‘af Scotland, in the room of Mr Cuartes Hope.

The office of Judge-Advocate, it had: hitherto, (I belicre),
been usual to execute by deputy; but Mr Tyrer was not of
a character to. make any compromise with duty, or to accept of
office, without accepting of all its obligations. He made it his
_ business, therefore, to attend upon every trial: he-gave to every
case his most careful and considerate attention ; and so anxious
was he-to fulfil his duty to the utmost, that he took the trouble
of drawing up, for his. own direction, a Treatise upon Martial
Law, which afterwards, when he retired from the office, he
gave to:the public, and which has (I-understand) been found
of the: most bn use in. - decision of cases: of this
ery 5 ae

Into the: detail of Mr Dveenicn’ s conduct in the — of
this delicate but important office, it would be presumptuous in
me to enter; but I may. be permitted to relate, from his corre:
spondenee, a.single incident, which illustrates both the con-
sciousness with which he discharged his duty, and the respect
in which his, opinion was held by those who were then.ati a
head of the Military Department.

_A court-martial had been held‘at Ayr, with the sentence of
ville Mr Tyrier-was extremely dissatisfied, and to the injus-
tice of which, he had: anxiously, but.in vain, endeavoured at
the time to awaken the attention of the Court. Upon trans-
mitting the proceedings to London, Mr Tyrirr thought it his
duty to communicate the grounds of his dissatisfaction. with:
the sentence to Sir Cnartes Morean, then Judge-Advocate-.
General, and, in the most earnest terms, to implore his atten-
tion to the case, if his Majesty should (as was probable) refer
it to his decision. Sir Cartes Morean cheerfully undertook
the

544 MEMOIR OF

the revision of the case: his opinion coincided in every respect
with that of Mr Tyrer; and to the letter in which Sir Cuarzes
communicated to him his Majesty’s disapprobation of the sen-
tence, Mr Tyrrer added the following note: “I have thus
“ had the satisfaction of procuring from his Majesty a disap-
** proval of this very unjust sentence, and a rectification of it
“in every point where it was wrong.”

In the year 1792, Mr Tyrrer had the misfortune to lose his
father, at the advanced age of eighty-one. Of the character of
this excellent man, the Society already possesses a description
by Mr Mackenzie, which no one will attempt to improve. The
loss to his son was of a kind which it is the fortune of few men
to experience. Their connection had subsisted for the long
period of forty-five years, undiminished by distance, and un-
broken by misunderstanding ; and there was so singular a cor-
respondence in their tastes, their pursuits, their principles, and
even their prejudices, that Mr Tyrurr felt he had not only lost
a father, but his best and oldest friend. His first employment
was to design a little monument to his memory, which he soon
after erected in the pleasure-grounds of Woodhouselee, upon a
spot which his father had particularly loved ; and he engraved
upon it the following inscription, which so well expresses the
filial tenderness of the author, and so happily obeys that pro-
found and merciful propensity of sorrow, which leads us stilk
to fill the scenes we love, with the presence of those we have
lost.

LORD WOODHOUSELEE. ; 545

M.S.
GULIELMI TYTLER, de Woodhouselee,
H. L. P. F.

En virides aras, en hance quam ponimus urnam,
Tu, fil ex manibus respice dona, Pater !
Sie, venerande Senex, olim qua rura placebani
Sint eadem busto nunc decorata tuo.

_ Neve Tibi desit post funera sueta voluptas,
Proximo ab umbroso cantet avis nemore,
Et qui Te placido lenibat murmure rivus,

Dulcia perpetuis somnia portet aquis-

By the death of his father, Mr Tyrier had succeeded to ‘the-
estate of Woodhouselee ; and some years before that period,
Mrs Tytxer had, in a similar manner, succeeded to the pater-
nal estate of Balnain in Inverness-shire. He was now in cir-
cumstances of aifluence,—his friends were numerous,—his own.
disposition in the highest degree hospitable and kind,—and he
felt himself at liberty to attempt to realise some of those visions
of retired and rural happiness, which had long played in his ima-
gi ation, and which form, perhaps, one of the earliest reveries:
ae generous or cultivated mind. He began, therefore,
immediately to embellish his grounds, to extend his plantations,
and in the enlargement of his house, to render it more ade-
quate to the purposes of hospitality; and in the course of a
short period, he succeeded in creating a scene of rural and do-
mestic happiness, which has seldom been equalled in this coun-
try, and which, to the warm-hearted simplicity of Scottish
manners, added somewhat of the more refined air of classical

| elegance.

546 MEMOIR OF

elegance. It was here, from this period, that all his hours of
enjoyment were passed,—that all his works were composed,—
and that, in the bosom of his family, and amid the scenery and
amusements of the country, he found the happiness that was
most congenial to his character and disposition.

His morning hours were uniformly given to study; but his
studies were of a nature that tended rather to animate than to
fatigue his mind. It was not in abstract or metaphysical spe-
culations he was engaged, where the understanding only is ex-
vercised, and where the progress of discovery is so little propor-
tioned to the time or labour that is employed ; nor in works
.of imagination, where the mind is ever in pursuit of that ideal
‘excellence which it is never destined to attain. The historical,
the antiquarian, or the critical studies in which he was engaged,
required no painful concentration of thought, and no laborious
processes of reasoning. They related to the deeds and lan-
guage of men, where it was not the understanding alone that was
employed, but where the imagination and the heart were per-
petually exercised ; and he could rise from them to the com-
mon business or offices of life, with a mind undistracted by
doubt, and unfatigued by abstraction. The employments to
which he gave his hours of exercise, were of the same gentle
and cheerful kind. He had little relish for the sports of the
field, unless angling, in which, like the amiable and contem-
plative Watton, he had from his early days delighted; but
he took great delight in gardening, in the embellishment of
his pleasure-grounds, and, more than all, in improving the
dwellings, and extending the comforts of his cottagers,—an
occupation, in which taste so fortunately combines with bene-
ficence, and in which, fer all the labour or expence he bestow-
ed, Mr Tyrer found himself every day rewarded, by seeing

the face of nature and of man brightening around him.
' The

:
i
‘

LORD WOODHOUSELEE. 547

The society that assembled at his table, was the best that at
that period this country afforded,—his own famil} y-relations,—
the families of the neighbouring proprietors in the populous
county of Mid-Lothian,—most of the men eminent in science
or in literature, of which our metropolis was then so profuse,—
and occasionally those strangers of distinction, whom the love
cof science or of nature had induced to visit Scotland. His hos-
pitality was cordial, but unobtrusive,—his attentions were so
uunostentatious, that his visitors found themselves at once at
home,—and he himself appeared to them in no other light
than as the most modest guest at his own table. The conver-
sation which he loved, was of that easy and unpremeditated
kind in which all could partake, and all enjoy. To metaphy-
sical discussion, or political argument, he had an invincible
dislike ; but he gladly entered into all subjects of literature or
criticism,—into discussions on the fine arts, or historical anti-
quities, or the literary intelligence of the day; and when sub-
jects of wit or humour were peated, the hearty sincerity of
his laugh, the readiness of his anecdote, and the playfulness of
his fancy, shewed to what a degree he possessed the talents of
society. His sense of humour was keen, but at the same time
characteristic: it was the ludicrous, rather than the ridiculous,
in character or in manners, which amused him: those excesses
rather of the amiable than of the selfish or sordid passions,
which are observed with a sentiment of tenderness as well as
of disapprobation, and which the poet has so happily express-
ed by the phrase, circum precordia ludit. The humour of most
men is unhappily mingled with qualities which add little to
the amiableness, and still less to the respectability of character.
From the gayest conversation of Mr Tyrzer, on the contrary,
it was impossible to rise, without a higher sense of the ed
of his taste, and the benevolence of nt nature.

VouVvil ee ee 3Z it IO B94 His

548 MEMOIR OF

His evenings were always passed in the midst of his family,
either in joining them in the little family concerts with which,
like bis father, he always wished to close the day, or in read-
ing aloud to them some of those works by which he thought
their tastes or their minds might be improved; or, not unfre-
quently, when none but his more intimate friends were pre-
sent, in sharing with his younger children in those various
youthful amuseinents which contribute so much to the gaiety
of domestic life, and in which the affections of kindred, and
the love of home, are so well, though so insensibly cultivated.

Of this scene of simple and virtuous happiness, there are
some present who will not easily part with the remembrance,
though accompanied with the melancholy reflection that they
can meet it no more; and Mr Mackenzie will, I trust, forgive
me for reminding him of an expression which he used to me
many years ago, when I accidentally met him upon the road as
he was returning from Woodhouselee, and which conyeys so
much better than any thing I can say, the character of the
scene. “ I hope,” said he, “ that you are going to Wood-
“ houselee ; for no man can go there without being happier,
“ or return from it without being better.”

To this picture, however, there is yet another feature to be
added : it is in the sentiments with which Mr Tyrer felt the
prosperity he enjoyed. In the little MS. volume from which I
have formerly quoted, (and from which I should more fre-
quently quote, if I did not feel it a kind of profanation to ex-
pose to the eyes of the world that train of secret thought which
was intended. only for the eyes of his children), I find the fol-
lowing passage, for the introduction of which, I am sure I need
no apology, and which expresses, in a manner which no bio-
grapher can do, the governing principles and persuasions of his
mind. It was written on his birth-day, 15th October 1795.

6h I

LORD WOODHOUSELEE. 549

«“ | have this day (says he) completed my forty-eighth year,
and the best part of my life is gone. When I look back on
“« what is past, [am humbly grateful for the singular blessings
“ T have enjoyed. All indeed that can render life of value,
“ has been mine. Health, and peace of mind;—easy, and even
“ affluent circumstances ;—domestic happiness ;—kind and af-
“« fectionate relations ;—sincere and cordial friends ;—a good
“* name ;—and, I trust in Gop, a good conscience. What
“ therefore on earth have I more to desire? Nothing; but if
“ He that gave, so please, and if it be not presumption in me
“* to pray,—a continuance of those blessings. Yet, if it should
“ be otherwise, let me not repine. I bow to His commands,
“ who alone knows what is best for his creatures; and I say
“ with the excellent Grorivus,

a
o

«¢ Hactenus ista: latet sors indeprensa futuri ;

Scit, qui sollicitum me vetat esse, Devs.

Duce genitor me magne! Sequar, quocunque vocabor,
Seu Tu lata mihi, seu mihi dura, paras.—

Sistis in hac vita? Maneo, partesque tuebor

Quas dederis. Revocas, Optime? Promptus eo.”

The melancholy change for which Mr Tyrrer seems thus to
have prepared his mind, was soon to take place. In the au-
tumn of the year 1795, he was seized with a long and dange-
rous fever, accompanied with delirium, and tending frequently
to relapse. Under the anxious care of his friend and physi-
cian Dr Greeory, he recovered from the fever; but in one of
the paroxysms of the disease, he had the misfortune to rupture
some of the blood-vessels of the bladder,—an accident which
not only protracted his recovery at the time, but which threa-
tened to degenerate into one of the most painful diseases to
which the human frame is subject. .

3 Z2 In

550 MEMOIR OF

In the state of weakness and suffering which succeeded this
severe illness, Mr Tyrier was for a long time incapable of re-
turning to his professional studies: but his mind was incapable
of inactivity; and he turned willingly to those pursuits in na-
tural history which had formed the amusement and the delight
of his youth, and which are perhaps of all others the most suit-
able to the grateful feelings of convalescence.

Among the works with which he now amused himself, was
the once celebrated treatise of Dr Dernam, entitled Physico-
Theology. In perusing it again, with all the affecting associa-
tions which the past .and the present afforded him, he could
not but lament, that it was in some degree rendered obsolete,
by the innumerable discoveries with which science has been
enriched since its publication, and that its popularity among
those to whom it might be most serviceable, was restrained by
the number of Latin quotations which remained without a
translation. It occurred to him that his hours of convalescence
could not be better employed than in remedying these defects,
and in thus extending the usefulness of a work of which he
had himself felt the value. This pleasing and unfatiguing
task he executed with his usual ardour, and prefixing to it a
short but valuable dissertation on Final Causes, published it in
the year 1799.

Of this work, it is unnecessary for me to enter into any fur-
ther detail; but I cannot omit a passage relating to it, which
I find among Mr Tyrxer’s papers, and which marks distinctly
the great principle by which his studies as well as his conduct
were governed.

“ Of all my literary labours, (says he,) that which affords me
“ the most pleasure on reflection, is the edition which I pu-
“ plished of Derham’s Physico-Theology. ‘The account of the
“ Life and Writings of Dr Dzruam, with the short disser-

“ tation

LORD WOODHOUSELEE. 55k

** tation on Final Causes, the translation of the Notes of the
Author, and the additional notes, containing an account of
‘those more modern discoveries in the sciences and arts
“which tend farther to: the illustration of the subjects of the
work, are all the original matter of the edition to which I
have any claim ; so that the vanity of authorship has a very
small share in the pleasure I enjoy from it. But when en-
‘gaged in that work, I had a constant sense that I was well
employed, in contributing, as far as lay in my power, to-
‘those great and noble ends which this most worthy man
proposed in his labours, by enforcing on the minds of man-
-kind-the conviction of an all-wise and. all-beneficent Author
of Nature. The» demonstration, in short, of that great and
‘central truth, on. which depends our present happiness and
-our future hopes. Since the publication of this edition,
some other excellent works have appeared upon the same
» subject, from which many valuable additions may be made
to the Notes.on Deruam; and-I intend, accordingly, to make:
those additions, if a-new edition should be wanted in my
“ lifetime.”

The year 1799 was distinguished by the agitation of the great
question with regard to the Union with Ireland ; and in attend-
ing to the debates it occasioned; Mr:'Tyrtxer thought that no:
view of the subject.could be better fitted to conciliate the minds:
of the Irish people to this important measure, than a represen-.
tation of the benefits which Scotland had derived: from the
Union with England. These observations he threw: into the.
form of a letter; and they were published at Dublin, with the
title of Ireland profiting by Example ; or the Question consider-
ed, Whether Scotland has gained or lost by the Union? Of this.
little work. it is enough to say, that.such was its merit, or its:

- popularity,

552 MEMOIR OF

popularity, that three thousand copies were sold upon the day
of its publication. ;

In the year 1801, a vacancy occurred in the Bench of the
Court of Session, by the death of Lord Sronerrerp. The
‘ friendship of Lord Mrtvite had a new opportunity for its
display ; and the friends of Mr Tyrrer had now the satisfac-
tion of seeing him elevated to the highest honours of his pro-
fession. On the 2d of February 1802, he took his seat upon
the Bench with the title of Lord Woopuovuseter.

Of Lord Woopnovseter’s qualifications for this important
office, it would be presumptuous in me to offer any opinion ;
and I feel, with gratitude, that it is unnecessary, as, of all the
honours which the Government of this country has to bestow,
those which have been in the estimation of the public most
purely won, and most honourably. worn, are those which belong
to the Administration of Justice. He brought not the Bench,
indeed, either that profound acquaintance with the details of
law, which nothing but continued and extensive practice can
give; nor that metaphysical acuteness, which so often seeks to
distinguish itself by subtlety of distinction, or novelty of inter-
pretation ; nor that impatient eloquence, which loves to find in
the most trivial cases, an opportunity for ifs own display. But
he brought to it qualities, in a country like this, of higher va-
lue, and of more genuine usefulness,—a just and enlightened
adiniration of the laws he was called to administer,—the most
conscientious patience in the investigation of truth,—and a
mind incapable either of being intimidated, in the discharge of
duty, by the dread of censure, or of being misled by the love
of praise. In his conduct on the Bench, the characteristic in-
tegrity and modesty of his nature were apparent. In this, as
in all other situations, his highest ambition was to be par ne-
goltis, non supra,—to be able to fulfil his duty without seeking

for

LORD WOODHOUSELEE. 55E

for personal fame; and to accommodate his conduct, not so
much to the opinion of men, as.to that higher standard, which
existed in his own breast. There-were, however, occasions when
his. powers were more peculiarly called forth ; and, upon some
of these appearances from the Bench, there are many of us
who can remember the high praise that was bestowed by the
late Lord President Brairn,—a man whose praise was fame,
and who was of too proud an integrity to bestow it where he did
not feel it was deserved.

From the period of his. elevation to the: Bench, Lord Woop-
HousELEE devoted his time exclusively, (while the Courts were
sitting,) to the business that arose; but, during the vacations,
he was always happy to return to his private studies. The so-
litude of the country, (to which he then always retired,) invited
him to labour; and as he was now free from his academical
engagements, and from that continued attention which the im-
provement of his lectures occasioned, he had time to return to
the consideration of some of the literary projects which he had
formed in his earlier days, and which he hoped he might now
be able to resume. One of these, I find, was the literary and
political Life of Bucnanan ; a subject which was interesting to
him from many associations, and in which he proposed to do.
ample justice to his genius as a poet, and his merits as a histo-
rian, but to examine, with firmness and accuracy, his conduct:
as a man, and as a politician.

Another was to give a faithful translation of Campen’s An=.
nals of Elizabeth, iliustrated with notes, and comparing it with.
the best accounts of her time that have since been published.
The subject had been suggested by Dr Campzett in the Bio-
graphia Britannica, and in the view which Lord Woopnouse-
LEE took of it, it promised him the opportunity of exhibiting a
fuller and more faithful picture of that interesting period in.

English.

554 MEMOIR OF

English history, than had yet been accomplished in any one
performance in our language. The most important, however,
of these literary projects, was that of a continuation of Lord
Hartes’s Annals of Scotland, from the period when Lord
Hares’s researches closed, to the accession of James VI. to
the Crown of England; a work to which no common talents
were adequate, and of the difficulty of which no stronger evi-
dence can be given, than that, however desired, it has yet re-
mained unattempted.

All these projects, however, yielded to another, which was
much more interesting to Lord Woopnouserre himself, and
to the accomplishment of which he was animated by some-
thing more than the hope of literary fame,—this was the Life
of his earliest friend and patron Lord Kamrs. ‘ He had wait-
“ ed, (as he says,) with his usu-] modesty, for more than twen-
“ ty years, in the hope of its falling into abler hands.” He
was now raised to the same Bench isi had been dignified
by the presence of Lord Kames ; and the business in which he
was engaged, served every day to bring him to his remem-
brance, and to afford him the new opportunities of appretiating
his learning and his genius. From this fortunate concurrence
_of circumstances, Lord Woopuovse.re felt himself emboldened
to undertake the task, and having determined upon his plan, he
entered with eagerness upon the study of his works, and the
collection of materials; and in the course of the vacations of
only four years, he was able to accomplish his design. The
work was finally published in two volumes, quarto, in the year
1807, with the title of Memoirs of the Life and Writings of
Henry Home, Lord Kamrs.

It is impossible not to admire the motives which led Lord
Woopuovsetze to this undertaking, and it is impossible also
not to respect the ability with wont amid the distractions of

public

LORD WOODHOUSELEE. 555

public business, and the sufferings of infirm health, he has been
able to execute it; yet 1 know not if the friends of Lord Woon-
HOUSELEE’s literary fame have not some reason to lament his
choice of a subject ; and there are circumstances in the extent
and variety of Lord Kames’s powers, which seem to me to
place him almost beyond the reach of the biographer.

The fortunate subjects of biography are those, where some
powerful and uniform interest is maintained,—where great
minds are seen advancing to some lofty and determinate ob-
ject,—and where, amid the toils or the difficulties they have to
encounter, the mind of the reader feels somewhat of the same
anxious and unbroken interest, with which we follow the pro-
gress of the drama, or the narrative of the epic poet. The lives
-of conquerors, and of legislators,—of discoverers in science,
_or of inventors in the arts,—of. the founders of schools in phi-
losophy, or of sects in religion, it is impossible even for the
rudest hand to trace, without awakening an interest which ail
men can understand, and in which all can participate; and
even the history of inferior men can yet always be made inte-
resting, when one object of ambition is seen to be steadily pur-
sued, and one correspondent sympathy is awakened. Of this
unity of pursuit, and of interest, the Life of Lord Kames was
singularly destitute. There was a vigour in his powers, and
an elevation in his ambition, that were incapable of being re-
‘strained within the limits of any one pursuit ; and he seems to
have felt it to be his peculiar destiny, to take the lead in
every science by which the reputation of his country could be
-exalted, and in every art by which its prosperity could be in-
creased. To delineate the progress of such a mind; to follow
his steps in all the various fields of inquiry through which he
travelled,—to mark with precision the accessions that science
derived from his labours, or the arts from his suggestions, was

Von. VIII. P. II. 4A a

ied

556 MEMOIR OF

a task to the execution of which, few men could bring adequate
knowledge or capacity ; and, even if it could have been execu-
ted, there were still fewer readers who could preserve any con-
tinuity of interest in a progress so eccentric, or be able to
make perpetual transitions from the subtleties of metaphysics
to the details of husbandry, or from the refinements of philo-
sophical criticism, to the technical questions of Scotch law.
The emblem of Lord Kames’s genius was not that of the Gan-
ges or the Indus, which roll forward their condensed streams,
and fill the eye of the spectator with their simple and increa-
sing’ majesty ; but that of the Rhine or the Nile, which divide
the volume of their waters into innumerable branches, and,
while they fertilize a wider surface, yet perplex the eye, that
labours to number and pursue them. What fidelity and affec-
tion could do, upon a subject so difficult, Lord WoopnovusELEE,
I apprehend, has done. He has given the portrait of Lord
Kanes, with all his various and characteristic features ;—he
has surrounded him with his contemporaries, and sketched out,
in many pleasing and interesting details, the literary history
of the age in which he lived ;—and his work, like those of Pia-
‘ro and of Xrnornon, will descend to posterity with an interest
which no other can now possess, that of being executed from
the living subject, and of blending the veneration of the dis-
ciple with the fidelity of the historian.

In the year 1811, Lord WoopuovsELEE was appointed to
the Justiciary Bench, on the elevation of the Lord Justice-
Clerk Horr to the President’s chair.

Although Lord Woonuovserner was now advancing in age,
and his strength declining, yet the publication of the Memoirs
of Lord Kames did nat put a period to his literary activity.
It was now too late, indeed, for him to resume any of the lite-
rary projects which he had once hoped to accomplish : but he

returned

LORD WOODHOUSELEE. 557

returned willingly to another occupation, with which he had
always intended to close his literary career. This was the re-
vision of his lectures upon history. In the composition of
these lectures, the best years of his life had been employed,
and at the distance of time that had intervened, he was now
able to review them with the eye of impartial criticism, and to
make such additions or alterations as might better fit them for
that general usefulness for which they were .originally intend-
ed. To this pleasing occupation all his remaining seasons of
leisure were devoted ; and with the usual chearfulness of his
temper, he flattered himself, that he might be able to accom-
plish a revision of the whole of the lectures that composed
his Academical Course. As the first great subject of these
lectures related to Grecian History, he now began anew the
study of the Greek historians ;, and as his views included the
history of science, of literature and of the fine arts, he was
Jed insensibly to the study of the moralists, the orators and the
poets, of that interesting period. So fascinating to his mind
was the occupation, that, in the course of a few vacations, he
was able to compose anew the whole of his lectures upon
Grecian History, and to be rewarded by that peculiar delight,
(which has been so often observed in the later years of literary
men,) the delight of returning again to the studies of their
youth, and of feeling, under the snows of age, the chearful me-
mories of their spring.

In the year 1812, the death of his friend and relation Gene-
ral Sir James Crate, (the late Governor of Canada,) and the
property to which he succeeded. by his will, rendered it neces-
sary for Lord WoopuouseELze to undertake a journey to Lon-
don. -As Sir James Craic had been distinguished by the Order
of the Bath, it became the duty of Lord WoopuousEteExz, as his
nearest relation, to return to the Prince Regent the ensigns of

4A2 the

558 MEMOIR OF

the Order ; and for this purpose his Royal Highness was piea-
sed to grant him an audience. Of this interview Lord Woop-
HOUSELEE always spoke with gratitude, not only as it afforded.
him the opportunity of observing that dignified courtesy by
which the manners of the Prince Regent are distinguished,
but as it shewed him the intimate acquaintance which his Roy-
al Highness possessed with regard to the affairs of Scotland,
and the interest which he took in her progress in science and
in literature. Some time after the interview with the Prince
Regent, it was intimated to Lord Woopuouszxez, that, if agree-
able to him, the dignity of Baronet would be conferred on him,
which he requested permission to decline,—an instance of mo-
desty, which surprised no one to whom Lord WoopuousELEE
was known; and which (I am proud to say) was to none so ac-
ceptable as to his own family, to whom no illustration could
be so dear as that of their father’s name.

I am led, besides, to mention this journey of Lord Woop-
I0USELEE to London, as it gives me the opportunity of intro-
ducing a little composition to which it gave occasion, and which
ought not to be omitted in any account of his life. He had for
some time believed, that the disease under which he Jaboured
was soon to be fatal; and a little before this, he had given or-
ders that his family burial place should be repaired, and had
inscribed upon it an epitaph, full of tenderness and of affec-
tion, to the memory of his father and his mother. In leaving.
London for the last time, and returning to his own country, it
was natural for him to look forward to the event which he had
long thought approaching, and to that final home where he was
to rest with his fathers. Under these impressions the follow-
ing lines were composed, as he was returning homewards; and
as they afford a picture of his mind which no Biographer could

' reach,

LORD WOODHOUSELEE. 559
reach, I trust I need no apology for introducing them in this
place. . i

ae

The Verses are entitled :

I~ Sepulchrum meum avitum, in Cemeterio Francisconorum,
Edinburgi, nuper re-zedificatum.

Jam duodecimum condere lustrum
Contigit,—et jam cernere canos
Vertice summo, dum fatiget
impigra quondam membra gressus,
ony Nec oculi vigeant nec aures,
ty? - Hebeat et prorsus sensuum acumen.—
—Hee sunt nec tarde indicia mortis.—
Hisce admonitus Fati nunciis,
Refici avitum denuo Sepulchrum °
Curo, et cineris protegi injuria
Mistz ut amicis reliquiis cubent,,
—Hic enim juncti quondam vita
(Nec sivit divelli fatum),
Dormiunt una Pater et Mater, ‘2
Purusque et pius ordo Parentum.——
Salve ! O vitai Anchora et Portus-!’
| Salve ! laborum terminus et quies!

Salve ! brevi subeundaque tecta.
Hospitium viatori fesso !
Te specto impavidus ; te longam.
Per noctem fidus sis custos,

Et reddas (precor) incolumem DEO.

The event to as Ford Woopnousetze thus steadily look-
ed forward was now approaching. In June 1812, after super-
intending

560 " -MEMOIR OF

intending his workmen in some improvements he was making
at Woodhouselee, he felt that he had fatigued himself, and he
was soon sensible of the recurrence of the same unfortunate
accident which had laid the foundation of so many years of
suffering. From this period, the remainder of his life was a
scene of coittinued pain and increasing debility,—borne, in-
deed, with the most calm and even chearful resignation, and
relieved by every thing that filial and conjugal tenderness could
supply, yet too visibly approaching to a period which neither
tenderness nor magnanimity could avert.

In the beginning of winter, he was prevailed upon to leave
his favourite Woodhouselee, and to remove into town; and
from this time his disease appeared to make a more rapid pro-
gress. On the 4th of January 1813, he felt himself more than
usually unwell ; and in the evening, when his family, with their
usual attentions, were preparing to read to him some work of
amusement, he requested that they would rather read to him
the evening service of the Church, and that they might once
more have the happiness of being united in domestic devotion.
When this was finished, he spoke to them with firmness, of the
events for which they must now prepare themselves: He assu-
red them that to him death had no sorrow but that of leaving
them: He prayed that Heaven might reward them for the un-
interrupted happiness which their conduct and their love had
given to him; and he concluded, by giving to each of them
his last and solemn blessing.

After the discharge of this last paternal duty, he retired to
rest, and slept with more than his usual tranquillity, and in the
morning, (as the weather was fine,) he ordered his carriage,
and desired that it might go out on the road towards Wood-

houselee. He was able to go so far as to come within sight of
his

——— = —.

LORD WOODHOUSELEE. 561

his own grounds; and then raising himself in the carriage, his
‘eye was observed to kindle as he looked once more upon the
hills, which he felt he was so soon to leave, “and which he
“ had loved so well.” There was an influence in the scene
which seemed to renew his strength, and he returned to town,
and walked up the stair of his house with more vigour than he
had shewn for some time; but the excitement was momen-
tary, and he had: scarcely entered his study, before he sunk
down. upon. the floor, without a sigh or a groan. Medical as-
sistance was immediately procured, but it was soon found that
all. assistance was vain; and Dr Grecory arrived in time only
to close his eyes, and: thus. to give the final testimony, of a.
friendship which, in the last words that he wrote for the press,
Lord Woopuousetze had gratefully commemorated as heniog
borne the test of nearly half a century...

_ His remains were interred. im. the family butialsplace.i in), tlie
Gucabiics Church-yard, beside those of his father and. mother,
to whose memory it was then found, that his filial, piety had
so exclusively dedicated it, that their epitaph occupied the
whole of the tablet, and no room. was: left: for any fusctiptiag:
to himself. > Jawa

Vi > *4h

~ Thave very ill executed the melancholy task I have under-
‘taken, if it is now necessary for me to conclude this account:
with any laboured delineation of the character of Lord Woop-:
HOUSELEE. I am Speaking to some, in whose memories his vir-
tues are written in better characters than those of words; and.
“I am too conscious of the partiality of friendship, to trust my-
self to any other ni pape igs than that ot his ‘own life:

(rey

‘and

562 MEMOIR OF

and conduct can supply. Upon his literary character, it will
be the province of posterity to pronounce ; and to it I willing-
ly leave to determine the rank he is to hold among the writers
of his country. To us in these moments, when we are again,
as it were, leaving his grave, there are other reflections that
belong ; and there are recollections of no vulgar kind that
arise, when we review the life of which we have seen the
close.

It was a life, in its first view, of usefulness and of honour.
He was called to fill some of the most important offices which
the constitution of human society affords,—as a father of a fa-
mily,—a possessor of property,—a man of letters,—and a
Judge in the Supreme Courts of his country; and he filled
them all, not only with the dignity of a man of virtue, but with
the grace of a man whose taste was founded upon high prin-
ciples, and fashioned upon exalted models. It was a life, in
its second view, of happiness as well as of honour: happy in
all the social relations which time afforded him,—in the esteem
of his country,—the affection of his friends,—the love and the
‘promises of his children: happy in a temper of mind which
knew no ambition but that of duty, and aspired to no distinc-
tion but that of doing good: happier than all in those early
and elevated views of Religion, which threw their own radiance
over all the scenes of man or of Nature through which he pas-
sed, and which enabled him to enjoy every present hour with
thankfulness, and to look ferward to every future one with

hope.

The records of this Society contain the histories of greater
men,—of none, I believe, more virtuous, more amiable, or
more happy: And while the lives of these illustrious men,

' (written

=.

LORD WOODHOUSELEE. 563

(written by men of kindred genius,) will, I trust, long continue
to inspire in this place the spirit of philosophical ambition, I
dare to hope, that even the faint outline which I have now gi-
ven of the character of Lord Woopuovse.er, may tend to che-
rish that moral ambition which all men are called to indulge ;
without which learning is vain, and talents are dangerous, and
to which rewards of a nobler kind are assigned, than either the
praise of men or the splendors of literary fame.

Vor. VIII. P. Il. 4B APPEN-

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APPENDIX.

Containing Lists of the Orricr-Brarrers and Mempers elected
since November 1815.

November 1815.
OFFICE-BEAREBRS.

Sir James Hatt, Baronet, President.

Lord Mrapowzank, l ia
Right Honourable Lord Gray, oe

Professor Piayrarr, Secretary.
James Bonar, Esq. Treasurer.
Tuomas Attan, Esq. Keeper of the Museum and Library.

PHYSICAL CLASS.

Sir Grorce Macxenziz, Baronet, President.

Tuomas Cuartes Hort, M. D. Secretary.

Counsellors.
James Bryce, Esq. del
Davin Brewster, LL. D.
4B2 Sir

566 APPENDIX.

Sir Witu1am Forzes, Baronet.
Awprew Coventry, M. D.
Professor Leste.

Lord Wess Szymouvr.

LITERARY CLASS.

Henry Mackenziz, Esq. President.
Tuomas Tuomson, Esq. Secretary.

Counsellors,
Reverend Dr Jamreson.
“et, Watter Scort, Esq.
Lord GLen ee.
Dr Tuomas Brown.
Witiiam Arzurunot, Esq. Lord Provost.
James Pitians, Esq.

22d January 1816.

MEMBERS ELECTED.
Captain Tuomas Cory, Royal Engineers.
Leonarp Horner, Esq. F. R. S. Lond.
Henry Co.esrooke, Esq.
Rev. Grorce Cook, D. D. Laurencekirk.
Right Honourable Witiram Avam, Lord Chief Commis-

sioner.

Joun Fuiierton, Esq. Advocate.
Tuomas

APPENDIX. 567

Tuomas Jackson, LL.D. Professor of Natural Philosophy,
St Andrew’s.

Joun Rostson, Esq.

Henry Dewar, M. D.

Mr Hvuew Morray.

Mr Roserr Witson, Accountant.

November 1816.
OFFICE-BEARERS.

Sir James Hartz, Baronet, President.

Lord GLEenLez, ae,
Right Honourable Lord Gray, } a ast

Professor Prayrair, Secretary.
James Bonar, Esq. Treasurer.
Tuomas Azan, Esq. Keeper of the Museum and Library.

PHYSICAL CLASS.

Sir Grorce Mackenzie, Baronet, President.
Tuomas Cuarzes Horr, M. D. Secretary.

Counsellors.

Sir Wiru1am Forzss, Baronet.
Anprew Coventry, M. D.
Professor Lxsutr.

Lord Wess Seymour.

Colonel Imrie.

Professor JamMEsoN.

LITE-

568 APPENDIX..

LITERARY CLASS.

Henry Mackenzie, Esq. President.
Tuomas Txomson, Esq. Secretary.

Counsellors.
Dr Tuomas Brown.
Witiiam Arsutunot, Esq. Lord Provost.
James Pitians, Esq.
Professor Dunrar.
Reverend Dr Macxknient.
Reverend ArcuiBaLp ALISON.

27th January 1817.

MEMBERS ELECTED.
The Honourable Baron Cuerx Rarrray. —
Right Honourable the Earl of Wemyss and Marcz..
The Honourable Davin Douctas, Lord Reston.
Francis Bucnanan, M. D. F. B.S. Lond.
Joun Wirson, Esq. Advocate.
Davw Hosack, M.D. F. R. S. New York.
Right Honourable Avexanper Maconocuir, Lord Advo-

cate.
Joun Freminc, M. D. late of Calcutta.
Davin Joun Hamittron Dickson, M. D. Clifton.
Wiuiam P. Arson, M. D.
James SKENE, Esq. of Rubislaw.

Dr Howe. ,
Rey..

APPENDIX. 569

Rev. Rozert Moreneap.
Roserr Batp, Esq. Civil Engineer.
Tuomas Sivricut, Esq. of Meggetland.

November 1817.
OFFICE-BEARERS.

Sir James Hatt, Baronet, President.

Lord GLEenLer, Vice-Presid
i t Je
Right Honourable Lord Gray, i 7 eae
Professor PLayrarr, Secretary.
James Bonar, Esq. Treasurer.

Tuomas Auian, Esq. Keeper of the Museum and Library.

PHYSICAL CLASS.

Sir Grorce Macxenziz, Baronet, President.
Tuomas Cuarzzs Hore, M. D. Secretary.

Counsellors. ©
Lord Wess. Seymour.
Professor Lrstir.
Colonel Imriz.
Professor JamEson.
Davin Brewster, LL. D.
Mr James Jarprne.

LITE-.

570 APPENDIX.

LITERARY CLASS.
Henry Mackenzix, Esq. President.

Tuomas Tuomson, Esq. Secretary.

Counsellors.

James Pitians, Esq.
Professor Dunzar.

Reverend Dr Macxnieur.
Reverend Arcurpatp ALIson.
Lord Reston.

Rey. Dr Jamigson,

26th January 1818.
MEMBERS ELECTED.

Tuomas Mackenzix, Esq. younger of Applecross.

Wittiam Ricuaxrpson, M. D. Harrowgate.

Honourable Captain Wituiam Napier, R. N. of Merchi-
stoune.

Harry Wittiam Carrer, M. B. Oxford.

Parrick Miter, M. D. Exeter.

Nartuanret Bownrtcu, Esq. Salem, Massachusetts.

Joun Craic, Esq.

Joun Warson, M. D.

Captain Tuomas Brown.

Joun Hors, Esq. Advocate.

Major James Auston.

Wiiu1am Fercuson, M. D. Inspector of Hospitals.

Sir Witu1am Hamitton, Baronet, Advocate.

END OF VOL. VIII.