GLEANINGS 
IN 
SCIENCE. 
JVo. 27. — March, 1831. 
I Observations upon the natural Water Cements of England, and 
on the artificial Cements that may be used as substitutes for them . 
By C. W. Pasley, Lieut. Col. in the Corps of Royal Engineers, 
F. R. S., &c. 
[From a pamphlet published by authority in England.] 
INTRODUCTION. 
In 1826, in consequence of having received directions the year before, that Prac- 
tical Architecture was, in future, to form a part of the course of instruction for 
the Junior Officers of the Corps of Royal Engineers attending this Establishment ; 
I was induced, whilst investigating the general properties of limes and cements, to 
try a great number of experiments, in hopes of obtaining an artificial water ce- 
ment from chalk and clay, all of which failed ; owing to the neglect of a precaution 
usually observed in respect to bodies about to be subjected to chemical analysis, or 
prepared for chemical combination, but of the necessity of which I was not at that 
time aware. 
In 1828, Major Reid having come to Chatham for a few months, requested me 
to show him in what manner I had proceeded in those experiments ; and the origi- 
nal stock of clay, which was procured from a considerable distance, having been 
expended, a different kind was used, as being nearer to the spot, which to our mutual 
surprise, for I had prepared him for certain failure, formed a very good artificial 
cement. This mere accident led me to resume, under more favourable circum- 
stances, an investigation that I had entirely given up, and since that period, many 
hundred experiments of a satisfactory nature have been tried upon the subject of 
artificial cements, a detailed account of which will probably hereafter appear in the 
Transactions of the Royal Society, and which will also be noticed in an Essay on 
Practical Architecture, that I propose to publish. 
In the mean time, under an impression, that the inferences drawn from these 
experiments, might be very useful to Engineer Officers, especially in the Colonies, I 
had previously condensed them into as brief a form as possible, in the following 
paper, which contains all the Rules applicable to practical purposes, and which 
having been laid before Major-General Sir Alexander Bryce, the Inspector General 
of Fortifications, and through him submitted to his Lordship the Master- General, 
and the Honourable Board of Ordnance, has been so far honoured by their appro- 
bation, that I have received authority to print a hundred copies for circulation in 
the Department. 
NEW SERIES, NO. III. 
