36 . Scientific Proceedings, Royal Dublin Society. 
by digging, extends some two miles west of the Bann, then 
narrows in the form of a great triangle, towards Coleraine. It is 
absolutely flat, only a few feet above the level of the Bann, 
and at such a height that it would ke covered at times of inunda-- 
tion. Rocks and stones that are covered when the Bann is in 
flood have on them a thin skin of diatomecious deposit, so that one 
is irresistibly led to the conclusion that the deposit is laid down 
when the Bann is flooded, and that the deposition is going on now. 
That the water, highly charged with silicious skeletons of diatoms, 
comes pouring out of Loch Neagh, and deposits this infusorial 
earth in the quiet waters of the flooded portions. The great store- 
house of the Kieselguhr is Loch Neagh itself, and the deposit on 
the banks of the Bann is as nothing to the immense deposit there 
must be on the bottom of the Loch. Of course this is a point that 
cannot be finally settled by speculative considerations such as the 
above, but must be determined by actual dredging, which will 
mean a certain amount of expense. 
The commercial uses of Kieselguhr are numerous, firstly, for 
dynamite, but the dynamite manufacturer states that the particular 
forms of the organisms in the county Antrim IGeselguhr are not 
those best suited for making dynamite, a tubular form giving, I 
am told, the best explosive effect. Mieselguhr, however, has 
many other uses for which thousands of tons a year are required, 
and are now shipped from the Continent to London. It is one of 
the best non-conductors of heat and sound, and is superior to all 
other materials for covering boilers and steam-pipes, for lining 
fireproof walls, floors, safes, and refrigerators, and its extreme 
lightness should specially recommend it for all such uses on board 
ship, and especially for lining fireproof bulkheads, for which one 
would imagine a very ready market would be found at Belfast if 
it were put in the proper form for consumption. 
