20 Dr, Boase, on a New Oxide 



It is, perhaps, unnecessary to remark that this figure is 

 contained within an inverted cone, and the above mode of 

 representation has been preferred as being better capable 

 of shewing the details. 



114. These figures are seen with best effect when conical 

 vessels made of blue or green glass are employed, the con- 

 trast of the light coloured powder and the dark ground 

 upon which the figures rest, appeal to the eye better than 

 when white glass is employed. 



1 15. All the experiments contained in the present paper 

 depend greatly for their success upon the newness of the 

 glass vessels, and the bows ; the latter should have horse 

 hair of the stoutest kind capable of great tension, and 

 rosin should be applied sparingly ; a few days work, how- 

 ever, renders the hair quite useless, and active vibration 

 has similar effects on glass vessels also. An old bow and 

 glass that has been much employed often prevent results 

 which with new instruments are immediately obtained.* 



Salisbury, March, 1836. 



Article III. 



On a New Oxide similar to that of Donium. By Henry S. 

 BoASE, M.D., Secretary of the Royal Geological Society 

 of Cornwall, 



To the Editor of the Records of General Science. 



Sir, — I have just read, in your last number, Mr. Richard- 

 son's interesting account of the oxide of Donium, which he 

 has recently discovered in Davidsonite. If I am not mis- 

 taken, it is precisely the same substance as one which I 

 have also found, and for which I had intended to propose 

 the name of Treenium, from Treene the place where it was 

 obtained. 



I might have announced my discovery to the public, as I 



• Since the date of the ahove paper, one of the methods proposed (106) for oh- 

 taining the figures in the interior of a conical glass by sifting lycopodium into it, 

 has been successfully adopted, the only precaution necessary to insure success, 

 being the employment of new glasses and a good bow. By new glasses, I mean, 

 such as hare not been employed in vibratory experiments. — C. T. 



