16 
of the Society the conditions under which the palaeolithic 
implements are found in the river-strata and in the caves, 
in association with the extinct mammalia, such as the Mam- 
moth and woolly Rhinoceros. Although the number of 
flint implements from the river-strata in various collections 
was very great, yet it is small when viewed in connection 
with the emormous quantity of gravel removed in their 
discovery. They are not evenly distributed, but cluster 
round certain spots. Their discovery in India along with 
the extinct mammalia proves that man was living, both in 
Europe and in southern Asia from the Ganges to Ceylon in 
the same rude uncivilised state, at the same time in the life- 
history of the earth. He also called attention to the art of 
the hunters of the reindeer and mammoth in the south of 
France, Belgium, and Switzerland, an art eminently realistic, 
and by no means despicable, and he inferred from their art 
and implements and the associated animals that they may 
be represented at the present day by the Eskimos. 
“ On a Colorimetric Method of Determining Iron in 
Waters,” by Mr. Thomas Carnelley, B.Sc. Communi- 
cated by Professor H. E. Roscoe, F.R.S. 
Of late years the analysis of water has become of such 
importance that any improvement in the methods employed 
in that analysis will, it is thought, be acceptable, however 
small such improvement may be ; and it is with this consi- 
deration that the following paper is submitted to the 
Society. 
In the determination of heavy metals in water, with the 
exception of lead, great inconvenience arises from the want 
of rapid and accurate methods of estimating very small 
quantities, and it is to remedy this inconvenience in the 
case of iron that the following method is proposed. Besides 
accuracy it fulfils both the other requisites, viz. rapidity and 
the power of determining exceedingly small quantities ; for 
without any evaporation 1 part of iron in 13,000,000 parts 
of water can be detected and a determination made in less 
than fifteen minutes; the smallest amount of ammonia 
