THE 
LONDON, EDINBURGH anp DUBLIN 
PHILOSOPHICAL MAGAZINE 
AND 
JOURNAL OF SCIENCE. 
SUPPLEMENT ro VOL. XIV. FOURTH SERIES. 
LVI. Observations upon the Structure of Glaciers. 
By Joun Batt, M.R.LA., F_L.S.* 
oy a few of those who have paid attention to the interesting 
questions connected with the movement and structure of 
glaciers, have long felt that, in spite of the efforts of many able 
men who had observed the phenomena on the spot, and of the 
progress made towards understanding their physical theory, for 
which we are chiefly indebted to Professor J. Forbes, much still 
remained both of fact and theory that called for further investi- 
gation on the part of men who should combine habits of careful 
observation with a mastery over the principles of physical science, 
The paper read last January before the Royal Society, by Pro- 
fessors Tyndall and Huxley, followed by a lecture delivered at 
the Royal Institution by the first-named gentleman, has been 
welcomed by such persons as a material advance towards the 
completion of our knowledge on these subjects. 
The theory of glacier motion may, indeed, be now considered 
complete. Professor Forbes had proved that glaciers in their 
gradual descent move after the manner of viscous fluids ; Prof. 
Tyndall has now brought to light that property of ice by which 
rigid masses of glacier are enabled to conform themselves to the 
laws that regulate the motion of imperfect fluids. 
The question remains, whether the able and ingenious authors 
of the paper read before the Royal Society have been equally 
successful in explaining the physical causes of the singular and 
complicated structure which careful examination detects im all 
known glaciers ; and with a view to satisfy some doubts on this 
subject, I endeavoured, during a recent visit to the Swiss Alps, 
to observe with attention such peculiarities in the structure and 
arrangement of those glaciers which I was able to visit, as might 
help to test the sufficiency of the new theory. 
* Communicated by the Author. 
Phil, Mag, 8, 4, No, 96, Suppl, Vol, 14. 21 
