-1859] WRITINGS OP JOSEPH HENRY. 375 



of public meetings, increases the tendency of lightning to 

 fall on the edifice. The inductive action will be slightly in- 

 creased when the audience assumes a standing position. 

 For a similar reason sheep which are crowded together dur- 

 ing a storm are frequently killed by lightning. The fact 

 has several times been noticed that when a discharge passes 

 through a number of animals arranged in a straight line, 

 those which are at the extremities of the row suffer most ; 

 and this has been observed even when the animals were not 

 in immediate contact with each other, as for example a 

 number of horses in a series of stalls. It is probable that 

 the heated air between the horses may have served as a con- 

 ducting medium, and that the effect can be referred to the 

 increase of intensity which always takes place in the electri- 

 cal discharge at the points where the air is ruptured, or 

 where the electricit}^ enters and passes out. 



The probability of injury from lightning is slight, even 

 in this country where thunder-storms are comparatively 

 frequent in the summer; and though it may be well to 

 observe proper precautions, yet on account of the small risk 

 to which we are subjected we should not deprive ourselves 

 of the gratification of observing and studying one of the 

 most sublime spectacles of nature; and indeed we know of 

 no better way of overcoming the natural dread which many 

 persons have of this meteorological phenomenon than by 

 becoming interested in its scientific principler^, and in study- 

 ing, in connection with these, its appearance and effects. 



Effects of the introduction of gas and water pipes. — Since tlie 

 use of gas has become so general in our cities as to be con- 

 sidered almost one of the essentials of civilized life, a new 

 source of danger has been introduced. Persons who repu- 

 diate the use of lightning-rods because they attract the elec- 

 tricity from the clouds should reject the introduction of gas 

 — particularly in the upper stories of their dwellings, since the 

 perpendicular pipes must act as the most efficient conductors 

 between the cloud and the earth. We say the most efficient 

 because they are connected below the ground with a plexus 

 of pipes, in many cases of miles in extent, the whole of which 



