1809. ] 
To the Editor of the Monthly Magazine. 
SIR, 
HASTEN, through the medium of 
your Magazine, to thank Mr. Hume 
for his notice of my opinion, which I 
have since found to be of long standing* 
in the chemical world, and was in a manner_ 
forced upon me in my walks among an 
infinity of flints, and in the neighbour- 
hood of chalk pits. Ic certainly does 
militate strongly against the tenets of 
Mr. Hume, who, 1 am confident, will 
not take offence at my observing, that 
his communication on the subject has ra- 
ther tended to strengthen my former con- 
viction. As my general pursuits are lit- 
tle calculated to qualify me for -discus- 
sions of this nature, I deprecate any thing 
like a spirit of controversy, and ‘shall 
therefore briefly give my reasons for not . 
relinguishing an opinion, to which I can 
adhere only from its greater probability. , 
1. If flints are abraded or dissolved 
into nodules, how ig it, that the outside 
coating, in such specimens when hollow, 
correspond with that within, being no- 
thing more than chalk, the flint existing 
wregular between the two? The solution, 
or abrasion, would scarcely begin in the 
centre, as well as on the surface. 
2. Many flints have taken the interior 
form of shells; and one which I have 
in my possession bears the impression 
(external) of a cornu ammonis. Here 
the flint must have heen in a soft state. 
Dr. Gregory, in his Economy of Na- 
ture (B. 6, c. 14,) says expressly, 
« Flint often shews evident marks of hav- 
ing been in a soft and tough state, like 
glue or jelly.” 
3. White limestone and chalk are the. 
matrices of flints; the latter forming ge- 
nerally a thin stratum between two beds 
ofthe former. This does not look like 
solutions of flint; but rather like a 
change of chalk into flint, by water 
which has filtered down the surface of 
the earth, carrying with it that iron and 
alumine, which constitute the general 
attendants upon pure silex. 
4. These flints, when deprived of the 
water of crystallization, become white 
and opaque, without their former charac- 
teristic hardness, and effloresce like 
neutral salts. This appears, as if they 
returned as far as their nature, depend- 
* «¢ The Abbé Bacheley has asserted, 
that marine productions, such as polipiers, 
shells, &c. are capable of passing to the state 
of gun-fiint.’=-Journal de Physique, Sup- 
plement, 1782, t. xxv.eeChaptal’s Chemise 
try. Vol. ii. p, 125, ; 
Further Remarks on the Formation of Flints. 
29 
ing upon certain -combinations and 
changes effected by that water, and the 
ingredients introduced by it, will permit, 
into its oriyinal state of chalk. | 
5. May not the small particles of flint 
found in chalk, tend to prove the dispo- 
sition of this earth for such transmuta- 
tion? With respect to the other ingredi- 
ents of chalk, I would: venture to ask, 
if they are not all found upon the calci- 
nation of flints, or its decomposition by 
the flaoric acid! As far as I can learn, 
they can be all procured from such ope- 
rations, If so, the association of the 
two is not altogether unnatural. It may 
exhibit the yualities of an acid, by the — 
adoption of carbonic acid from the cal- 
careous earth, or of oxygen from the 
water. But here we want experiments, 
By these I could wish it to be ascertain- 
ed—ist. What are the constituent parts 
of that external coat of flints, which ad- 
heres to the tongue, and seems to he the 
first change the chalk undergoes, or that 
part which is not sufficiently altered toe 
wards a state of flint from a want of the 
water, and the ingredients brought with 
itf-—2dly. What are the component 
paits of the next coat of white opaque 
flint ; what is gamed, what is lost, &c. ?— 
3dly. A clear and accurate analysis of 
the commont gun-flint.—4thly. The 
same process with regard to common 
chalk, in which the flints are bedded. 
The experiments by fire, and by the 
fluoric acid might, perhaps, furnish some 
data for general conclusions. I know 
not what has been done towards a dis- 
covery of the nature of fiints, by Voltaic 
electricity. It is possible the result may 
be as favourable as in its application to 
limes, | 
Upon the whole subject, however, jet 
me be understood to speak under cor- 
rection ; and in what I have said, rather 
to express my desire, that some one, 
better able than myself, may bestow that 
attention upon this production of nature, 
which its great uses and universality seem, 
to deserve. 
Your’s, &c. A. BC, 
Lo the Editor of the Monthly Magazine. 
STR, 
HE total disregard of truth and 
justice, manifested by the con= 
ductors, and principal writers of the 
Edinburgh Review, has been long so no _ 
+ I learn, from the above author, that 
Wiegleb obtained, from an analysis of com- 
mon brown silex, per quintal, 80 silex, 16 
alumine, and two iron. 
a -toiious, 
