1896.] MICROSCOPICAL JOURNAL 393 



had been cracked, water bad infiltrated through the 

 cracks. The water which came in poured with it the 

 pulverized, smashed, and crushed atoms of broken crys- 

 tals, and strewed over the projecting peaks and pin- 

 nacles of the carbonate of lime, a perfect shower as if a 

 snowstorm had descended upon the Alps. A curious 

 thing was that in the clefts of these peaks he had found 

 the sporangia and the scale of a fern. Some of the 

 nuts were filled with quartz sand just like that pre- 

 served at the Royal Baths, and on searching through 

 this they found curious evidences of organic remains. 



The microscope showed him a spray of 8elagiuella 

 absolutely to be identified, while close by were a number 

 of the spines of Echini. These must have been washed 

 into the nut through cracks. Projecting from the sides, 

 or lining the testa of the nuts, crystals of strontia were 

 found, being readily recognizable by their blue tinge 

 and their radiating fan-shaped distribution. There was 

 also arragonite. Carbonate of lime, when mixed with a 

 little strontia, would frequently yield arragonite, but 

 the latter was very apt to fall from the surface on 

 which it was formed, as it had in the case of one of his 

 best specimens that evening on the way to the Institu- 

 tion. They found in these crystals curious evidences of 

 change of temperature. In many instances a change of 

 temperature had caused the carbonate of lime to take 

 the form of arragonite and in others the form of calcite. 

 The strontia crystals, radiating and bundled like a 

 closed fan, had a magnificent sheen upon them, and 

 were remarkably beautiful. 



If they took the analysis of Bath waters, they would 

 find it stated in some of them that traces of strontia 

 were found; in other instances, it would be said that 

 traces of strontia were suspected. Was it not an inter- 

 esting thing, therefore, that what by chemical analysis 

 of the water was " suspected " or barely traced, they 



