238 Scientific and General Memoranda. 



opening was soiled, and the sentinel, as soon as he was free from 

 the annoyance he suifered from the thrusts repeatedly made at 

 his body, approached the foreign substance to taste it, and evi- 

 dently disliking the material, he withdrew into the hive. A troop 

 of bees was soon observed to advance, towards the place, each 

 individual bearing a small particle of wax, or of propolis, in his 

 mandibles, which he deposited in his turn upon the soiled part of 

 the wood. The little labourers then returned to the hive, and 

 repeated the operation until a small pile rose above the blemish- 

 ed part, and consequently relieved the inhabitants from the an- 

 noyance. — Beechey^s Voyage. 



On preventing the Discharge of a Bullet from a Gun by the finger. — 

 At the sitting of the Helvetic Society of Natural Sciences of 

 the 20th July 1830. A letter was read from Dr. Flachin of Yver- 

 dun, relative to an experiment before mentioned to the society, 

 in which the ball was prevented from leaving the bottom of a 

 musket when the gunpowder was fired, simply by putting the 

 ramrod upon the ball, and the end of the finger upon the ramrod. 

 He supposes the effect may be explained by the circumstance, 

 that near the charge, the ball has a very small velocity compared 

 to that impressed upon it by the expansive force of the gases of 

 the fired gunpowder, when exerted during the whole of the time 

 in which it is passing along the barrel. It is well known that the 

 effect thus accumulated is the reason why long pieces carry fur- 

 ther than short ones, and why the breath of a man, which can- 

 not exert a pressure of more than a quarter of an atmosphere, 

 may, by means of a tube, throw a ball to the distance of sixty 

 steps. The experiment requires great care, especially as to the 

 strength of the piece, which is liable to burst in the performance 

 of the experiment. — Journal of Royal Institution. 



Penetrativeness of Fluids. — Dr. J. K. Mitchell's paper on this 

 subject, is republished in the number for August 1831, of " the 

 Journal of the Royal Institution of Great Britain," with the fol- 

 lowing observation : " The generality and importance of this 

 paper is such, that we think it quite impossible to convey an idea 

 of it by an abstract, and feel ourselves bound to bring it before 

 our English readers at full length." 



