Ixxul PROCEEDINGS OF THE GEOLOGICAL SOCIETY. 
Such have been the labours of the Geological Society of London 
since the last Anniversary ; they have neither been slight nor unim- 
portant ; they have extended from our own land to the antipodes, in 
one dectinn by North America, and in the other through India ; 
they have embraced a variety of subjects, palezeontology, said its ap- 
plication in identifying contemporaneous deposits having formed a 
prominent part of them. It is evident that we have not been idle or 
neglectful of that science for the cultivation and extension of which 
we are associated, and that, therefore, we have assisted to promote 
the progress of knowledge generally, and consequently the well-being 
of our fellow-men. 
GEOLOGICAL SOCIETY OF IRELAND. 
Our sister society in Dublin has, as heretofore, been active in pro- 
moting the advance of our science in Ireland. The earliest commu- 
nication made to it during the year was by Sir Robert Kane, on the 
occurrence, in the county Clare, of carbonate of manganese as a thin 
earthy bed, interposed between a decomposed surface of old red sand- 
stone and a bog, two feet deep. To all appearance this carbonate of 
manganese is of comparatively recent origin. Respecting mineral sub-— 
stances a valuable paper was read by Dr. . Apjohn upon an undescribed 
variety of hyalite from Mexico, where it is found in large glossy, 
transparent, globular concretions. It is considered a hydrate of silica, 
containing about 2°5 of water, and was found by the optical researches 
of Dr. Apjohn to be formed of a confused aggregation of microscopi- 
cally minute rock-crystals. This result will be appreciated by those 
acquainted with hyalite, a mineral exhibiting at first sight few traces 
of crystalline arrangement, and it at the same time proves the value 
of optical methods of research in the examination of mimerals. 
Another communication of interest respecting mineral substances - 
was made by Professor Oldham. Among the many alterations in 
the structure of the various beds of the older fossiliferous rocks of 
the counties Wicklow and Wexford, caused by the protrusion through 
them of the granites, is one wherein the component parts of the 
beds have been so acted upon that crystals of andalusite are abun- 
dantly formed amid micaceous slates, themselves altered argillaceous 
slates. The crystals of this mineral, sometimes of large size, occur 
in multitudes, crossing each other in all directions. Among these 
Prof. Oldham discovered some which had themselves been again re- 
placed by mica, the latter occupying the space once filled by the mat- 
ter of the andalusite, and its cleavage planes usually running across 
the principal axis of the original crystal, though sometimes occurring 
in planes perpendicular to every surface of it. This movement of the 
particles of matter, taking place at different times, without the bed- 
ded or laminated structure of the original rock being lost, in conse- 
quence of actual fusion by contact with the adjacent molten mass of 
granite, is one of no small geological importance when the laminated 
crystalline rocks, forming whole regions in some parts of the world, 
are under consideration. Prof. Oldham points out that Mr. Weaver 
