Intelligence and Miscellaneous Articles. 471 



regulate the escape. A very little practice enables the operator to 

 determine the quantity so as to produce the maximum of heat. 



The usual experiments as performed by the apparatus I have 

 thus, 1 tear, imperfectly described, are, if I may be allowed the use 

 of the expression, infinitely more splendid and more impressive 

 than can be effected by any other means with which I am ac- 

 quainted. The lime experiment, especially, is inconceivably bril- 

 liant, exhibiting a disc of pure white light 1^ inch in diameter. 

 With a piece of clock-spring I have filled an area of 3 feet dia- 

 meter with the most beautiful coruscations. 



The advantage of this apparatus is that of sufficient capacity 

 that one or two charges will be sufficient for a course of illustrative 

 experiments in a lecture-room. There is not the slightest dan- 

 ger of explosion. It is more powerful and more striking in its 

 effects than any other instrument. 



I shall have great pleasure in furnishing any further details that 

 may be required. — i\Iight not vessels of sufficient strength and ca- 

 pacity be constructed in which a store of gas could be kept at the 

 most important light-houses, to be used in thick weather, in further- 

 ance of Lieut. Drummond's plan? 



Dr. Faraday has informed me that about the time that Clarke's 

 blowpipe was invented, an instrument somewhat similar to mine 

 was shown him, and was, he believes, described in the Phil. Mag. 

 But that instrument consisted of one vessel only, divided by a 

 diaphragm. Hence there was no security against an explosive mix- 

 ture forming in either of the chambers through a defect in the metal. 



Lyiiiington, Hants, Sept. 10, 1832. 



NOTICE OF A MARINE DEPOSIT IN THE CUFFS NEAR FAL- 

 MOUTH. BY R. W. FOX. 



Many persons are no doubt aware, that in some parts of the cliff's 

 between Falmouth and Helford harbours, there exists an horizontal 

 bed of rolled quartz pebbles, gravel and sand, similar in every respect 

 to the materiiils which prevail on the contiguous sea-shore. Hence 

 it cannot be questioned that the origin of both is the same ; and 1 

 think it may also be assumed, from the above-mentioned materials 

 being in many parts arranged in separate layers in the bed, that the 

 sea must have frequently risen to its level. 



The thickness of the^bed varies from one to three feet and upwards, 

 and it is situated generally about nine to twelve feet above the level 

 of Uie highest spring tides. 1 luive not yet extended my observations 

 on this bed beyon<l about four miles of coast, but within these limits 

 it seem.s almost everywhere to exist when the cliffs are not composed 

 of .solid rock. This bed does not appear to penetrate far into the 

 clifl', if we may judge from the few parts where it has been broken 

 away or cut through. In one place I have observed it about eight 

 feet, and in another twenty, within the face of tlie cliff. The rocks 

 on this coast arc of clay-slate, having a very considerable underlie,' 

 mostly towards the S.E. ; but the bed in question is found only in 

 tiio.-5C puits of the tlilF which arc composed of earth, stones, and de- 



