THE EFFECTS OF LIGHTNING. 81 



Of the flames which issue from the earth and form objects upon it, the most } 

 common and most frequently observed are those which have appeared on the ? 

 points of spears, and more frequently still on the extremities of the masts and 

 yards of ships. These were observed by and known to the ancients long before 

 electricity assumed its place among the sciences. When they appear in two 

 flames on the masts and rigging of vessels seamen call them Castor and Pol- 

 lux, when as a single flame, Helen. The latter is regarded as an evil omen, 

 the former a presage of a favorable voyage. Passing over many examples of 

 these phenomena of remote date, and which might be considered of doubtful 

 accuracy, we shall here state a few of the more recent instances of them. 



On the 25th of January, 1822, during a heavy shower of snow, M. de Thi- 

 elaw, on his route to Freyburg, observed the branches of the trees in a heavy 

 shower of snow, to emit a bluish light. 



On the 14th of January, 1824, immediately after a storm, a large black cloud 

 overspreading the sky, M. Maxadorf saw a wagon on which a load of straw 

 was transported into the middle of a field, near Cathen, and observed that the 

 blades of straw stood on end, and seemed to be on fire, a vivid flame also is- 

 sued from the whip of the driver. This appearance lasted about ten minutes 

 and ceased when the wind had dispersed the cloud. 



On the 8th of May, 1831, some officers of the French engineers and artil- 

 lery were walking after sunset, with their heads uncovered, on the terrace i 

 of Bab-Azoun, at Algiers. Each looking at the others observed with unquali- { 

 fied astonishment, that the hairs of his companions stood on end, and little jets 

 of flame issued from them. When the officers raised their hands, similar jets 

 issued from their fingers. 



Similar phenomena are seen to issue from the pointed extremities of steeples 

 and other elevated structures. 



IX. LUMINOUS RAIN. 



The following are the proofs and examples of the occurrence of this class 

 of phenomena collected by M. Arago : 



On the 3d June, 1731, Hallai, prior of the Benedictines of Lessay, near 

 Constance, states that he saw in the evening, during a thunder-storm, rain fall 

 like drops of red-hot liquid metal. 



In 1761, Bergman wrote to the Royal Society of London that he observed 

 on two occasions, toward evening, and when no thunder was heard, rain which 

 sparkled as it struck the ground, which seemed to be covered with waves of 

 fire. 



On the morning of the 22d of September, 1773, in the district of Skara, in 

 East Gothia, in Sweden, a thunder-storm broke, attended by very violent rain. 

 The rain commenced at six o'clock in the evening. All the accounts agree 

 in stating that the drops struck fire and scintillated on touching the ground. 



On the 3d of May, 1768, near La Canche, about two leagues from Arnay- 

 le-Duc, M. Pasumot was caught on an open plain by a violent storm. The 

 rain-water collected abundantly on the leaf of his hat, and when he stooped his 

 head to let it flow off, he observed that in its fall, encountering that which fell 

 from the clouds a^t about twenty inches from the ground, sparks were emitted 

 between the two portions of liquid. 



On the 28th of October, 1772, on his way from Brignai to Lyons, the abbe 

 Bertholon was caught in a storm at five o'clock in the morning. Rain and hail 

 fell heavily. The drops of rain and the hail-stones which struck the metallic 

 parts of the mounting of his horse's trappings, emitted jets of light. 



A friend of Howard, the meteorologist, on his way from London to Bow, on 



VOL,. II. 6 



