MISCELLANEOUS MINERALS. 5 II 



Bailej', Matthew and Ells, in their report (present Eeport of Progress) infusorial 

 on the geology of that region. XewBrunswick 



The sample, the results of the examination of which are here given, 

 came from Pollet Eiver Lake, Mechanic Settlement, King's County, 

 New Brunswick, and was collected by Mr. E. W. Ells. It occurs in 

 considerable quantity, the deposit in this lake being, it is stated, about 

 four feet deep, and can be readily obtained, either by dredging or 

 draining the lake. A couple of slides of this material were prepared 

 and placed in the hands of Mr. J. F. Whiteaves for microscopic exam- 

 ination. This gentleman informs me that the deposit would appear to 

 be of fresh-water origin ; that it contains siliceous spicules of Spongilla 

 in great abundance, also quantities of frustules of diatomacese, mostly 

 detached, among which he has recognized the following genera, viz ; 

 Pinnularia, Surirella, Stauroneis and Himantidium. 



In texture it resembled an earthy chalk ; very fine grained but harsh 

 to the feel ; adheres to the tongue ; colour light greyish-white. Heated 

 in the closed tube, assumes a dark-grey colour, due to the separation 

 of carbon, and gives off an abundance of a somewhat ammonical, light 

 brownish-yellow coloured water — the material evidently containing 

 nitrogenous organic matter. After ignition, with free access of air, 

 its colour is reddish-white ; if treated with hydrochloric acid previous 

 to ignition, the colour is white or at most has a just perceptible reddish 

 tinge. 



When digested, either before or after ignition, with a boiling solution 

 of caustic potash or soda, the silica readily passes into solution, leaving 

 a small amount of insoluble residue, which after ignition has a light 

 reddish-brown colour. The insoluble residue readily subsides from the 

 solution, this latter, if the material has been treated before ignition, 

 has a brownish-yellow colour; if after ignition, and consequently when 

 free from organic matter, the solution is colourless. 



This sample had been kept in the dry atmosphere of the laboratory 

 for a lengthened period, and was regarded as perfectly air-dried. At 

 100° C, the oxygen of the air exercises a modifying influeuce upon 

 this material, so that, in order to ascertain the correct loss by water at 

 this temperature, it is necessary that the operation should be con- 

 ducted in an atmosphere of hydrogen or carbonic acid. 



