To Benjamin Franklin from William Franklin, 12 July 1753
From William Franklin
AD: American Philosophical Society
Philada. Thursday July 12. 1753
On Sunday last, about 45 Minutes after 3 in the Morning, a Dwelling House, one of a continued Row on the West Side of Second-Street in this Town, was struck by Lightning, but, being at that Time untenanted, no Person was hurt.1 About 6 aClock the same Morning, I went to take a View thereof, and at that Time made some Notes of the Course which I observ’d the Lightning to have taken in its Passage, and also of some of its Effects on the House, which then appear’d to me not unworthy of Notice.
The Course is as follows, viz.
The Lightning, or Matter thereof, (supposing it to have enter’d at the Top of the House, as is the general receiv’d Opinion), first struck the South East Corner of the Easter-most Chimney; from which Place it can be trac’d downwards, by Cracks and other Marks on the South Side of the said Chimney, in a Diagonal Line, to the Bottom of a Kind of Bulk-Head, or Place rais’d above the Roof, to go out on the Top of the House, and reaching from one Chimney to the other; that it then appears to have gone up the E. Side of the Roof, near the Edge of the S. Side of the Bulkhead, to the Ridge, and from thence descended the W. Side of the Roof, by the like Way, to the Bulk-head Door, which it split, and melted Part of an Iron Staple on the Inside of the Westermost Side of the Door Frame; that from thence its Course was continu’d down the W. Side of the Roof, by the S. Side of the Western Chimney, till it came to a Place where the Roof bent or slaunted downwards, along the Ridge of which Bent it turn’d and pass’d Southward to a Dormer Window, flat on the Top, and which projected about 3 Feet from the Roof, where again it turned, and by the upper and N. Side of the Dormer proceeded W. to the further End; that from thence it was conducted downwards by the Leads and Window-frame on the N. Side of the said Window to a kind of Pent-House, about 2 feet wide, the wooden Moulding on the under Side of which was much shatter’d, and a round Hole made therein, as if done by a Bullet fir’d from a common Swivel Gun; that its Course was then down to the Northermost Window of the 2d Story, where it diffus’d itself amongst the Leads, and went out at the Iron Window Hook, that hung down from the Southermost Side of the said Window, about a Foot below the Point of which it made a considerable Breach in the Wall, and drove the Plaistering on the Inside, to the opposite Side of the Roof that from thence it made a small crack in the Wall down to a Ledge (or single Row of Bricks projecting about 3 Inches from the Wall, which the Bricklayers term a Water Table or Water Fall) about mid-way between the Windows of the 1st and 2d Story, and from there plowing, or scooping, as it were, the outside of the Wall all the Way down to the upper and Southermost Part of the Northermost Window of the 2d Story, which it entirely drove into the Room; that the Lightning then diffus’d itself in the Leads, and descended by them to the Northermost Window Hook, from the Point of which it jump’d to the Upper and Eastermost Corner of a Window over the Door of a Kitchen adjoining to the Northermost Side of the back Part of the House, and fronting the South; that from thence it was conducted by Leads to the lower and Westermost Corner of said Window, from which Place it again jump’d across to the Kitching Window, at the Distance of about 2 Feet, making all the Way a Hollow in the Brick Wall between, as if done by a large Iron Scoop; that in this last Window it divided itself very much, as might be seen by the Leads, which were in most Places melted; that from hence no Traces of it appear, except just at the Points of the Iron Hooks, fix’d to each Side of the Window-Frames, which were about 2 Feet from the Ground; to where, it might have been conducted by the Moisture on the Walls, which was very considerable, there having a great Quantity of Rain fell the Night before.
Observations of the Effects.
1. That the large black cloud, from whence the Fire is generally thought to have issued, came from the South West, yet the Chimney on the back Part or W. Side of the House, tho’ equal in Heighth to that on the Front or East Side, and but about 9 Feet Distance, was not at all affected, its first Appearance upwards, as mention’d before, being on the S.E. Corner of the Eastermost Chimney.
2. That the under Part of one of the Bricks in a small Ledge that went round the Chimney, about a Foot from the Top, had a Piece knock’d out of it, as if done by a Blow of a Hammer, or some other Force from underneath; the Bottom of the Fracture being the whole Breadth of the Ledge, and the upper Part terminating to a sharp Edge, as is represented in the Margin; the upper Side of the Ledge was no otherways hurt than but by a small Crack proceeding from the Fracture underneath; and the Lightning appears, as if by the Resistance it met with from the Ledge, to have been forc’d into the Chimney, thro’ the Mortar between the Ledge and the Brick underneath.
3. That the East Side of the Roof, up which the Fire must have pass’d, supposing it to have enter’d from above, was noways damag’d, except just at the Ridge, where the thin Edge of the Shingles appear’d to have been thrown up by it; but the thick End of the Shingles lay perfectly close from the Bottom of the Eastermost Chimney to the Ridge, as did all those on the E. Side of the Roof.
4. That on the West Side of the Roof, quite from the extreme End of the Dormer Window to the Ridge, in the Track before described, the thick Ends of the Shingles are all thrown upwards, as if done by some Instrument forc’d underneath them.
5. That the Splinters near the Hole in the wooden Moulding of the under Part of the Pent-House, before described, were all drove upwards, as if occasion’d by a Bullet being shot against it from below.
6. That several of the upright Parts of the Window Frames were, in many Places, much shattered; and all the Pieces that were split or torn off from them, were broadest at the Bottom, and terminating almost to a Point at the Top; whereas the contrary might have been expected to have happen’d, if the Force which split them came from above.
7. That the under Side of the Ledge or Water-Table, between the 1st and 2d Storys, was considerably more damag’d than the upper, and a Piece drove out of it, as in the Ledge near the Top of the Chimney.
8. That the Lightning went considerably out of its nearest Way, (supposing it to have proceeded either from above or below) for the Sake of the Leads of the Windows, and Iron Hooks, Staples &c. of the Window-Frames; which were all much melted and stain’d thereby. Several Panes of Glass were also a little melted, and appear’d somewhat colour’d, round the Edges, near where the Leads surrounded it and those Parts of the Leads being thin, and not sufficient to conduct the whole of the Flash, were melted; but the thick Parts of the Leads, (which separate the Panes from each other) conducted it freely, and without being the least damag’d.
1. A brief account was printed in Pa. Gaz., July 12, 1753. The house was that of one Trumble, possibly Francis Trumble, a cabinet maker and Windsor-chair maker. PMHB, LV (1931), 304–5.