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[[column one]] SCIENTIFIC OBSERVATIONS Lightning andd Lightning-Rods The following paper on the storm of Mondday, May 25th, was read before the Meterological Section of the Franklin Institute, Last evening, by Prof. John Wise, and is reported expressly for the EVENING BULLETIN The thundergust that passed over the city on Monday afternoon, the 25th of May, was attended with more than the usual amount of electrical discharges. Immediately over the city the heavens were literally filled with flashes of light and brilliant corruscations of lightning. The cloud-matter was so thoroughly combined, and of such great thickness, that the usual echoes were not propogated, but, instead, we had the hoarse, rumbling intonations of thunder, resembling the sound of that produced by heavy carriages running over frozen ground. The thunderbolt discharges sounded much like the discharges of heavy artillery, while in smaller storms the sound resembles more that produced by small arms. While in all these storms there is a central vortex, those of great dimensions have within their areas a number of vortices. In that of Monday last the evidence of this feature of storms was discernible in the uprooted trees in different sections of the city. These vorticces are so much broken and shattered in passing over a city by the solid obstructions they meet in their whirling action that they become comparatively harmless; whereas, in passing over an orchard or woods, the umbrage of the trees presents a favorable condition to their impact, and many of them are twisted and lifted out by the roots. In addition to the great number of thunderbolts that were discharged upon the earth from the clouds, the vapor stratum over head was for half an hour embellished with brilliant horizontal scintillations of electrical fire, resembling the bursting of rockets filled with white stars. This display of electrical pyrotechnics was truly sublime. Many persons were reported as having suffered from these electrical discharges, but these sufferings were in most cases of the imaginary kind, distressing enough to be sure, but not very dangerous in their results. The pleasure afforded to those who view the phenomena in their beauteous and exhilarating aspects forms an equivalent to those who suffer from them. The most marked and instructive thunderbolt discharge brought to my notice was that which struck the building of Mr. Rech, on the southeast corner of Girard avenue and Eighth street. The building is provided with an extensive arrangement of lightning-rods. It is gravel rooted, and round the whole circumference of this roof there runs an iron rod conductor. From this horizontal iron bar there are perpendicular lightning-rods at sixteen different equi-distant places. It has, in fact, sixteen lightning-rods rointing to the clouds. Upon the roof and centering the avenue front, and about twenty feet from the front edge of the building, there stood a flagstaff. A branch of the circumferential conductor runs across to this staff and up it about twelve feet, where it ended and was fastened to an iron band around the pole. The thunderbolt, in disregard of the sixteen lightning-rods, struck the flagstaff, and completely shivered it down to within four feet of the iron band, and where the branch conductor ended. Why did this bolt prefer the wooden pole to the lightning-rods? Simply because it was in the path of the descending bolt. Now if, as claimed by eminent electricians, the rod does its sillent work fo discharging the cloud when it is yet afar off, did it not quietly and decently disarm this nimbuss artillery in this case? Certainly the garrisson was well fortified with these barbed protectors, expressly stationed there to prevent an explosion of electricity, by drawing the surcharge from the cloud, if not when yet afar off, at all events when the pending cloud passed over the protected building. The lightning-rod man claimed that the branch conductor carried off harmlessly the remainder of the bolt. No doubt it did, ssince that residue was of little momentum and energy of what was left of the bolt after having made splinters and kindling wood of a thirty feet flag staff. While this is the third flag-staff shattered by lightning in this city that I have examined within a few years, and where the mechanical effects of the bolt were little beyond that of rending the pole, it is the only one on a building where it was surrounded by a cordon of lightning-rods, or in proximity to a rod; it is one of the most conclusive evidences of the inutility of lightning-rods that could possibly be presented. If the rod would do what it is intended for, to wit: draw the surcharge of electricity from the storm cloud silently; disarm it of its force by drawing in a silent stream to its point, as the charge from the prime conductor of an electrical machine is drawn by any kind of a pointed material, glass as well as metal, there should not be a bolt ever descend upon a building in Philadelphia, with its thousands of lightning-rods peering toward the cloud region. The only protection from thunderbolt that has yet been proved to be efficacious is the metal roof. The greatest damage done to a building thus protected is the perforation of the metal at the point where the bolt strikes, and this is in the heaviest discharges, not over from a half in in diameter. Such has been the result of my observations through more than a quarter of a century. In all these observations I found the mechanical effects of the thunderbolt about the same in buildings that were struck, and with rods upon them, as those without rods, with this difference, that nearly all the cases of ignition were upon those with rods. Such are the facts of the case, with all the theories to the contrary notwithstanding. [[Column Two]] Metal has no more attraction for lightning than sponge has for water. In either case it may be viewed as an absorbent. Neither has a metal point an attractive power to draw electricity on it. Points act as recipients of conduction, or as entering wedges to the bolt, as a point would act in perforating a soap bubble of hydro-oxygen gas or any other film of attenuated matter. The attraction of a positive for a negative, as laid down in electrical science, proves nothing more than that there is present an unbalanced condition of electrical matter, and then necessarily a disposition to electrical equilibrium, which always follows, just as two drops of water will coalesce when their atmospheres come in contact. TUESDAY. JUNE 2, 1874. SCIENTIFIC OBSERVATIONS. Lightning and Lightning-Rods. The following paper on the storm of Monday, May 25th, was read before the Meteorological Section of the Franklin Institute, last evening, by Prof. John Wise, and is reported expressly for the EVENING BULLETIN: The thundergust that passed over the city on Monday afternoon, the 25th of May, was attended with more than the usual amount of electrical discharges. Immediately over the city the heavens were literally filled with flashes of light and brilliant corruscations of lightning. The cloud-matter was so thoroughly combined, and of such great thickness, that the usual echoes were not propagated, but, instead, we had the hoarse, rumbling intonations of thunder, resembling the sound of that produced by heavy carriages running over frozen ground. The thunderbolt discharges sounded much like the discharges of heavy artillery, while in smaller storms the sound resembles more that produced by small arms. While in all these storms there is a central vortex, those of great dimensions have withing their areas a number of vortices. In that of Monday last the evidence of this feature of storms was discernible in the uprooted trees in the different sections of the city. These vortices are so much broken and shattered in passing over a city by the solid obstructions they meet in their whirling action that they become comparatively harmless; whereas, in passing over an orchard or woods,the umbrage of the trees presents a favorable condition to their impact, and many of them are twisted and lifted out by the roots. In addition to the great number of thunder-bolts that were discharged upon the earth from the clouds, the vapor stratum over head was for half an hour embellished with brilliant horizontal scintillations of electrical fire, resembling the bursting of rockets filled with white stars. This display of electrical pyrotechnics was truly sublime. Many persons were reported as having suffered from these electrical discharges, but these sufferings were in most cases of the imaginary kind, distressing enough to be sure, but not very dangerous in their results. The pleasure afforded those who view the phenomena in their beauteous and exhilarating aspects forms an equivalent to those who suffer from them. The most marked and instructive thunderbolt discharge brought to my notice was that which struck the building of Mr. Rech, on the southeast corner of Girard avenue and Eighth street. This building is provided with an extensive arrangement of lightning-rods. It is gravel roofed, and round the whole circumference of this roof there runs an iron rod conductor. From this horizontal iron bar there are perpendicular lightning-rods at sixteen different equi-distant places. It has, in fact, sixteen lightning-rods pointing to the clouds. Upon the roof and centering the avenue front, and about twenty feet tron the front edge of the building, there stood a flagstaff. A branch of the circumferential conductor runs across to this staff and up it about twelve feet, where it ended and was fastened to an iron band around the pole. The thunderbolt, in disregard of the sixteen lightning-rods, struck the flagstaff, and completely shivered it down to within four feet of the iron band, and where the branch conductor ended. Why did this bolt prefer the wooden pole to the lightning-rods? Simply because it was in the path of the descending bolt. Now if,as is elaimed by eminent electritians, the rod does its silent work of discharging the cloud when it is yet afar off,did it not quietly and decently disarm this nimbus artillery in this case? Certainly the garrison was well fortified with these barbed protectors, expressly stationed there to prevent an explosion of electricity, by drawing the surcharge from the cloud, if not when yet afar off, at all events when the pending cloud passed over the protected building. The lightning-rod man claimed that the branch conductor carried off harmlessly the remainder of the bolt. No doubt it did, since that residue was of little momentum and energy of what was left of the bolt after having made splinters and kindling wood of a thirty feet flag staff While this is the third flag-staff shattered by lightning in this city that I have examined within a few years, and where the mechanical effects of the bolt were little beyond that of rending the pole, it is the only one on a building where it was surrounded by a cordon of lightning-rods, or in proximity to a rod; it is one of the most conclusive evidences of the inutility of lightning-rods that could possibly be presented. If the rod would do what it is intended for, to writ: draw the surcharge of electricity from the storm cloud silently; disarm it of its force by drawing in a silent stream to its point, as the charge from the prime conductor of an electrical machine is drawn by any kind of a pointed material, glass as well as metal, there should not be a bolt ever descend upon a building in Philadelphia, with its thousands of lightning-rods peering toward the clond region. [[Column Three]] The only protection from thunderbolt that has yet been proved to be efficacious is the metal roof. The greatest damage done to a building thus protected is the perforation of the metal at the point where the bolt strikes, and this is,in the heaviest discharges, not over from a half to an inch in diameter. Such has been the result of my observations through more than a quarter of a century. In all these observations I found the mechanical effects of the hunderbolt about the same in buildings that were struck, and with the roods upon them, as those without rods, with this difference, that nearly all the cases of ignition were upon those with rods. Such are the facts of the case, with all the theories to the contrary notwithstanding. Metal has no more attraction for lightning than sponge has for water. In either case it may be viewed as an absorbent. Neither has a metal point an attractive power to draw electricity on it. Points act as recipients of conduction, or as entering wedges to the bolt, as a point would act in perforating a soap bubble of hydro-oxygen gas, or any other film of attenuated matter. The attraction of positive for negative, as laid down in electrical science, proves nothing more than that there is present an unbalanced condition of electrical matter, and then necessarily a disposition to electrical equilibrium, which always follows, just as two drops of water will coalesce when their atmospheres come in contact. THE STORM ON THE FOURTH Thunderbolts, Flag-Staffs and Metal Roofs. Prof. John Wise made the following report to the Meteorological Section of the Franklin Institute, at its regular meeting last evening, July 6th, 1874: During the thundergust that passed over our city on Saturday last, between 5 and 6 o'clock P. M., the Eighth Police District Station-house, in the Buttonwood, below Eleventh street, was the recipient of a thunderbolt. The building is roofed with tin. Along the front margin of the roof an ornamental iron railing is erected, and a few feet in the rear of this stood a flag-pole, surmounted with a wooden ball of ten inches diameter. The thunderbolt hurled the ball into the street, just grazing a man's head; the pole was rent into many fragments, large and small, for half its length downwards; and from thence down to the level of the level of the roof it was driven and shattered, tearing the wood away from the many knot-pins, leaving the pins standing bare and unscathed. From the top of the remaining portion of the flag-staff it is plainly discernible that the force doing the work of destruction was gradually expended as it passed along; and as it approached the roof within several feet its violence was very much diminished. When it reached the level of the roof, and where the tin was turned up and around the staff, precisely there its destructive force was ended. The lower part of the staff, i.e. below the level of the tin, shows no sign of mechanical force. The tin turned up against the staff was bent outward in a southeast direction, indicating that the line of projection was from the northeast. No trace of force or heat was visible on the roof, but along the splintered edges of the staff traces of singeing were visible. The building adjoining on the west is also covered with tin. I deem this another expressive case of immunity from thunderbolt harm under the shelter of metal roofs. There are no traces of violence upon the wooden ball that capped the flag-staff. It would seem that the iron pin that fastened it on to the top of the staff transmitted the force right on to the pole. There is no lightning rod in the building. In the room of the telegraph operator, and where the instrument is standing, it made its appearance by darting out from the wire where there was an open or broken space of insulation of half an inch in length. The instrument was unprovided with a "lightning arrester," and the consequence was the heating of the wire to a red heat. The operator was but slightly shocked, and but for the metal roof would have experienced a more decided evidence of its manifestations. It is worth any electrician's time to go and see, in this case, how nicely the tin roof gauged the march of the thunderbolt. The best iron turret of a monitor could not possibly so well shield its inmates from the shot of heavy artillery as does the metal covering of a house its inmates from the destructive effects of thunderbolts.
Transcription Notes:
I wasn't sure if I was supposed to add the signature at the bottom written in pencil, and I couldn't really make out the first name so I didn't include it. I hope that's ok!
