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[[First Collumn]] Where a large surface or metal, as is the case in a tin-plate or sheet-iron roof, meets it by a law of affinity between metal and electricity well enough understood to assure us that the lightning will instantaneously traverse its whole surface, and thus be brought to a state of rest, by the dissipating power of a good conducting, or, we might say, a good absorbing material. In the many opportunities of examination which I have had I have never found a single case of thunderstroke that demonstrated an exemption of damage claimed by virtue of the rod but what I could offset by half a dozen exemptions equally good where there was no rod. The greatest amount of damage by far arising from thunderbolts is from the fire they enkindle, and these fires are oftener traceable to the lightning rod than they are to accidental nails or spikes, or other pieces of metal, in combustible matter of buildings subjected to its force. That any thatch or fibrous wood is liable to ignition from lightning stroke may be possible, though I never found an instance of it; as in buildings which were set on fire, having no rods on them, the ignition may have been the result of heated metal. It will not be out of place to remark, in conclusion, that there are nearly as many different explanations of the functions of the lightning rod and modes of its erection, as there are different authors of text books on physics. Mr Robert E. Rogers—I have listened with much interest to the communication of Mr. Wise, because it is upon a subject of deepest importance, one which needs our careful study and reflectior. We are apt to be a little shaken by such communications in our faith in the truth of those principles which have been regarded as established in reference to the laws of electricity. I therefore hope he will pardon me if I enter a sort of protest against some of the broader conclusions which he presents. I first desire to qualify, and then to admit much of what he has said. In the first place it is understood. I believe, that the lightning rod discharges the electricity of the thundercloud, not by mere conduction, but far anterior to the time of the direct blow of the lightning. The points of the rod assuming an opposite state to that of the cloud, and therefore, long before the cloud comes within striking distance, it is conceived as the result of experiment, to be disarmed to a considerable degree of its power. Then looking at the facts which have been collected with great care by Mr. Wise, I think there should be some qualification made in this direction. We are furnished with those cases wherein a house provided with a rod has been struck and fired, perhaps, but we have not been presented with those cases (which we believe to be very numerous) which have been provided with a lightning rod, along which a thunderbolt has passed harmless. We must not take the exceptional cases as the rule. Has we not protected our buildings with lightning rods, how many hundreds of thousands of buildings might there not have been struck by lightning? In reference to his remarks concerning the conducting power of the lightning rod I am exceedingly glad that he has drawn attention to the fact, for I believe there is a vast amount of quackery in the pitting up of lightning rods. There is a great variety of rods offered for sale, and people are induced to change from one to the other upon some representation of superior qualities. None of them as they are now proposed to be put up are really as they ought to be. The desire to make money induces the venders to put the smallest amount of metal in the rods, and they give some particular form to it as a substitute for what is really valuable. If a rod is made of thick, solid metal, is carried high up above the building, and deep into the earth, and provided with many points, I believe it will protect the building. Professor A. R. Leeds read the following interesting paper upon the effects of carbonic oxide gas: I accidentally respired some time ago a quantity of pure carbonic oxide. The gas was contained in a quart bottle, from which I inhaled certainly less than a pint, probably a quantity not exceeding a gill, into my lungs, previously exhausted, through expiration of atmospheric air. For a brief moment, no change of mental impressions or of bodily feeling was noticeable. The next, without any intermediate condition, I was struck senseless to the floor. Fortunately, the bystanders rushed immediately forward, tore open my clothing, poured water upon my wrists and head and applied violent friction to my limbs. The pulse had stopped beating, or beat so feebly that, in the agitation of the moment it was imperceptible; the chest had ceased to expand and contract, the complexion had acquired the livid hue of death, and the temperature of the body was rapidly falling. The operation of the carbonic oxide was so immediate as to prevent the lungs from the throwing off the single charge they had received, and the shock arising from the remedies employed probably enabled them to do so. A slight nausea, which passed off in the course of a few hours, and a dulness and oppression in the crown of the head, lasting some time longer, were the only effects which remained after restoration to consciousless. A number of interesting inventions were then exhibited by the secretary, the nominations for officers were made, and the meeting adjourned. [[Second insert in first column]] [[?]] Record. Philadelphia, Saturday, May 4, 1872. Local Record. Weather Report,,- Merchants' Exchange, May 3: 6 o'clock. 12 o'clock. 3 o'clock. Thermometer.. 53 60 62 Wind........... W.N.W. W.N.W. S.W.[[Smudged]] Barometer..... 29.93 29.93 29.85 Wagner Free Institute.- The lecture or Professor John Wise on the subject of "Thunder bolts and lightning," which was delivered at the institute on Thursday evening, brought together a large and appreciative audience. He commenced by saying that he had no speculative theories to subserve, but would simply relate the facts as observed in his investigations of the phenomena of lightning, and would then show by these facts that the lightning rod too often played the part of an incendiary. [[Second Column]] After reviewing twenty-nine cases of lightning stroke that occured in this city last summer, and showing that the greatest loss of property took place under the supposed protection of the lightning rod, he noted a large number of cases that occured in other places. The destruction of the extensive pattern shop of I. P. Morris & Co., and the Pekin wollen mills of Manayunk, both in this city, caused a loss of over a hundred thousand dollars, and both those establishments were defended by lightning rods. He stated that small bodies of iron, when struck by a thunderbolt, will scintillate vivid sparks, and thus ignite any adjacent inflammable matter. He also reviewed three cases of lightning stroke as they occurred in Iowa City, Terra Haute and Indianapolis where the lightning was communicated from the rod to the gas pipes in the buildings, set fire to the gas, and then passed out to the gas mains in the street, where, in one case, it burst the lead packed joints here and there for a distance of one thousand feet, and in the other two it totally burned out the lead packing, leaving nothing but a little dross in its place. The lecture was concluded by announcing the following as the conclusions derived from an examination of many cases during the last three years: That lightning is an accumulation of force in the cloud. That when the cloud becomes surcharged it explodes with a discharge always toward the earth. That is generally comes from the west and southwest. That its main force is in its axial line of projection. That it strikes buildings indiscriminantely as to lightning rod or no lightning rod, and that in either case its dynamic force appears to be the same. That when it strikes a bar of iron, as a spike or clamp, or even a shingle nail, it burns the surface and scintillates bright sparks, which are capable of igniting adjacent imflammable material. That a thunderbolt is neutralized the instant it meets its correlative equivalent of metal surface. That when it stikes the lightning rod, that being only a fractional quantity of its neutralizing equivalent, and the earth or water at the rod's terminal point being but a poor conductor (four hundred million times slower than iron--so said the learned Cavendish, and so says the noted telegraph electrician, David Brookes of this city), it meets a cul de sac, recoils and heats the rod sufficiently to melt its point and to scintillate sparks from its surface which set fire to the building. That in a house with a metal roof there is no danger of harm from a thunderbolt, either to persons or property. That whenever the lightning rod is struck by a thunderbolt it proves its own inefficiency, since Franklin's theory was that it would prevent thunderbolts, not catch them. That there is no reliable evidence of upward strokes of lightning, and that the recoil of a thunderbolt upon the rod is what leads to that notion. In addition to the cases referred to above, that happened in this city, several others of an instructive character were reviewed, prominent among which were the building at the corner of Twelfth and Chestnut, the Enon Baptist church, the Columbia engine house on Market street, a shed standing on a lot on Brown street, between Twenty-fourth and Twenty-fifth where a mule and dog were killed, and the British bark Vibilia, then lying near the iron and steel works on Delaware avenue. At the close of the lecture a number of diagrams, illustrative of the most conspicuous cases, were projected on a screen by Mr. Davis, who assisted Mr. Wise with a Marcer sciopticon. EVENING BULLETIN published daily, Sundays excepted, at THE BULLETIN BUILDING, 607 Chestnut Street. PEACOCK, FETHERSTON & CO. Tuesday, July 16, 1872. Meterological. Immunity from Thunderbolts. [Communicated by Prof. John Wise] During many years of observation of thunderbolt phenomena, I never found a metal-roofed building that had recieved any serious injury from a stroke of lightning, nor heard of any person being injured in such building by a thunderbolt, although I have examined many such buildings that were struck by the bolt. From these repeated cases it is a fair deduction that a thunderbolt may find its equivalent a neutralization in a certain amount of metal surface; that is to say, the projectile energy of the discharge will be entirely dissipated by the affinity of the metal for the electrical essence; I say essence, because I can find no better name to designate it, since it is not known to our philosophy what the thing really is. We acknowledge it, however, to be a mode of motion. A very expressive case of thunderbolt immunity occurred in this city on Saturday last. Wood's Museum, on the corner of Ninth and Arch streets, was the recipient of an electrical discharge. The building is roofed with tin. It has no lightning-rod on it, but on the front end it is surmounted with a flagstaff about 60 feet in height above the top of the building. The staff had on its top a wooden liberty cap which was covered with gold leaf, and it also carried a large flag. This flagstaff is supported in its place by three iron braces of an inch in thickness, which radiate from an iron collar around the staff five feet above the roof; and these braces are flattened at their lower ends and there firmly bolted and soldered to the tin roofing, forming a good electrical connection. The thunderbolt struck the staff from a westerly, but nearly perpendicular, direction and knocked off the liberty cap and tore the flag, passing down the staff on the side it struck, cracking and splintering it all the way down, to within eighteen inches of the iron band, from whence it seems to have darted upon the band and braces, and from these to the metal roof, where it was dissipated, showing no sign of violence upon the roof. The roof contains about seven thousand square feet of metal, and it is safe to say that this building, under this roof, has perfect immunity from strokes of lightning. It is as well defended against Jupiter's artillery as the best iron-clad ship is against gunpowder artillery. It is important that the people should know these facts, and in them learn the value of metal roofs as a protection to life and property from lightning strokes. - A Chinese murderer, who has given himself up, is named Ah Hung. He probably, ah, will be. 4 EVENING BULLETIN. The Philadelphia Evening Bulletin is published daily, Sundays excepted, at THE BULLETIN BUILDING, 607 Chestnut Street. The Evening Bulletin is served by carriers, at Eight Dollars per annum, payable at the Office, or Eighteen Cents per week, payable to the carriers; by mail, at Eight Dollars per annum, or Seventy-five Cents per month. PEACOCK, FETHERSTON & CO. Friday, July 14, 1871. COMMUNICATION [For the Philadelphia Evening Bulletin.] Thunderbolts and Lightning-Rods. The thunderbolt that caused the destruction of one of the extensive buildings of I.P Morris & Co., situated on Richmond street, in this city, on last Tuesday afternoon, is another strong proof against the efficiency of lightning rods in the protection of buildings. The buildings of this establishment form a quadrangle, with an open area of several acres, and the building destroyed occupied the main line of the southern side. It was surmounted with a wooden cupola, containing a clock, and the cupola had on it a spire carrying a metal ball and vane. The spire had connected with it a lightning-rod, which ran down to the slate roof of the building, and from thence, by an angle with the pitch of the roof, down to its eave, and from thence down the outside brick wall into the ground. The bolt, as witnessed by the writer and one of the employés of the establishment, descended in a perpendicular line, and the report of it was like the explosion of a shower of bomb-shells. The open area of ground between the buildings, and the street on the south side of the building, appeared to spectators of the phenomenon as covered with a lurid flame, and a gentleman connected with the establishment, who was standing in a rear door of the office building, looking upon the building struck, noticed two balls of fire flickering down the building as it was struck, and describes them as being the color of white-hot iron, surrounded with a bluish halo. Another individual saw a similar illumination upon the chain and weights of the clock coming down from the cupola. The first discovery of the fire was under the cupola, and indicated that the fluid glanced from the rod where it formed the angle with the pitch of the roof. The writer having made thunderbolt phenomena a subject of observation for many years, finds this flying off of the fluid at a tangent from angles in lightning rods not an uncommon occurrence. The cloud, as observed by an eye-witness, was black and appeared to be almost scraping the cupola. Query: why did not the rod discharge it silently? This building was full of iron brace rods, iron pillars, iron chains and hoisting machinery, and a large quantity of other iron fixtures. The rationale of the fire can only be found in the discharge of a large quantity of electricity upon the spire, vane and ball, in its passage from thence on to a half-inch bar of iron (the lightning rod), where it scintillated incandescent sparks upon the wooden combustible matter in proximity to the rod- a fact manifested in the writer's observations time and again in his investigations. It is a well-known fact that when a large charge of electricity passes over a small rod of iron it heats and burns the iron, and causes it to scintillate livid sparks, like those proceeding from the bar as being welded under the blacksmith's hammer.
