330 LETTERS ON NATURAL MAGIC. 



be less than two or three inches in diameter. 

 We set the gas on fire as it issued through the 

 water. It burnt for some time with a good deal 

 of splendour ; but as the rivulet was swollen, 

 and rushing along with great impetuosity, the 

 regularity of the issue was necessarily disturbed, 

 and the gas was extinguished." Dr. Thompson 

 found this gas to consist of two volumes of hy- 

 drogen gas, and one volume of vapour of carbon ; 

 and as its specific gravity was 0.555, and as it 

 issues in great abundance, he remarks that it 

 might be used for filling air-balloons. " Were 

 we assured," he adds, " that it would continue 

 to issue in as great abundance as at present, it 

 might be employed in lighting the streets of 

 Glasgow."* 



A very curious natural phenomenon, called the 

 Lantern or Natural Lighthouse of Maracaybo, 

 has been witnessed in South America. A bright 

 light is seen every night on a mountainous and 

 uninhabited spot on the banks of the river Cata- 

 tumbo, near its junction with the Sulia. It is 

 easily distinguished at a greater distance than 

 forty leagues, and as it is nearly in the meridian 

 of the opening of the Lake of Maracaybo, navi- 

 gators are guided by it as by a lighthouse. This 

 phenomenon is not only seen from the sea-coast, 

 but also from the interior of the country at 

 Merida, for example, where M. Palacios observed 

 it for two years. Some persons have ascribed 

 this remarkable phenomenon to a thunder-storm, 

 or to electrical explosions which might take place 

 daily in a pass in the mountains ; and it has 



* Edinburgh Journal of Science, No, 1, New Series, p. 

 71-75. 



