NOTES ON TWO LIGHTNING FLASHES. 139 



verandah, but saw nothing, but my younger son rushed in 

 and said that the lightning bad struck a gas pipe piercing 

 the wall of a workshop and had set the gas on fire. The gas 

 was at once turned off at the meter, and an examination 

 made. The workshop was covered, both as to roof and walls, 

 with galvanized iron, the sheets on the western side touch 

 the soil, those on the front not quite ; both have fair contact 

 with the roof ; also an iron fence which runs from the side 

 for about fifteen feet is embedded in the soil, which at the 

 time was very wet. Inside the building the gas pipe is of 

 iron, f inch, and comes from the main service through an 

 adjoining room ; the main service being of inch pipe, which 

 runs underground about 80 feet to the meter. The pipe 

 ends a few inches outside the iron shed and is joined to a 

 tin pipe, such as is often used in walls, which ran along 

 the top of a wooden fence, on a batten, to a small labora- 

 tory; and in it did not go nearer the floor than about 

 four feet six inches, where it terminated in the usual 

 appliances for lighting and heating. 



I found that the iron pipe, the building, and all the con- 

 tents were uninjured, but that from the brass union the tin 

 pipe was melted for some fifteen inches, and the tin 

 spattered about. The rest of the pipe to the laboratory 

 was uninjured ; it was afterwards replaced by \ inch iron 

 pipe as far as the laboratory. 



A sewer ventilator about six feet above the skillion roof 

 near its highest part at the back of the building pierced 

 the roof, and was well flushed to it, but it went only into 

 dry soil, and there of course into the top of the earthern 

 trap. No damage occurred to these. As the interval 

 between the flash and the extinguishing of the burning gas 

 was only about two minutes at most, it is pretty clear that 

 the heat of the lightning, that is of resistance, was respons- 

 ible for most of the melting of the tin pipe. The difficulty 



