198 



NA TURE 



[June 28, 1883 



before the accident occurred, having (as I understood) fallen 

 down from age. The upright is split vertically in two places, 

 one (where the piece was rent off) following exactly the line of 

 the small iron nails which fixed the laths (for the wall plaster) to 

 t'je upright, and the other about 2 inches to the east of this line. 

 At this east split the outer portion of the upright is forced out- 

 wards about 4 inches from the centre portion, and all but sepa- 

 rated from it. Along the line of the first split the lath nails are 

 forced out of the upright, and the lath enis pushed outwards, 

 and sime broken off. A great patch of the planter that covered 

 them (the centre of it being about 4 feet above the floor) is torn 

 off and thrown vi rlently against the north wall of the building 

 on the opposite side of the room 21 feet distant. The wall is 

 dotted (high and low) with white powdery marks, and the floor 

 at the foot o c it is covered with broken and powdered plaster, as 

 also is (more or less) the space of intervening floor. The splits 

 in the upright unite upward-, and pass through the loft floor at 

 a comparatively small orifice, and the piece rent out tapers con- 

 siderably from the bottom upwards. The rent surface of this 

 piece is minutely fretted in a curious manner. In the bottom of 

 the rent oft piece (which comprised the greater part of the sec- 

 tional area of the post at this end) were three or four 2 J-inch 

 iron nails, probably used for fixing the post to the floor. These 

 appeared to be driven and bent into the wood ; there was no 

 sign of fusing on them, and the surlace of the floor immediately 

 underneath the bottom of the post was not in the slightest 

 degree damaged, so far as could be detected. On each side of 

 the slight brickwork forming the east wall of the dormer or 

 porch, a small patch of plaster (about 6 inches square or so) 

 was broken off close to the flonr, and about 3 feet southward of 

 the post, but no other marks attributable to the explosion (and 

 these small pa'ches might have been due only to the concussion) 

 could be discovered at the second floor. 



On entering the room below (on the first floor), which has no 

 ceiling, it was found that the wooden girder (9J x 4A), on which 

 the post rested, had a splinter 16 inches long and about I inch 

 square (on an average) torn horizontally off the east side of it, 

 3 or 4 fe=t to the southward of the position of the bottom of the 

 post, and about 6 feet from the south wall. The girder extends 

 across the room, and rests on the north and south walls. Below 

 the splinter, on the same girder, there was a horizontal crack, 

 extending through the breadth of the girder, and proceeding 

 about 8 feet along it northward, but stopping short of the posi- 

 tion of the pot above. It seemed, however, possible that there 

 might be yet another horizontal split in this girder close to the 

 under side of the floor above, and extending right up to the 

 position of the post. Along the west side of the girder is a 

 short joist (7 inches by 3 inches) passing through the south wall, 

 extending about 4 feet into the room, and fixed to the girder by 

 three large iron trenails ; and just below it thire was some 

 more slight woodwork bedded in the wall, and apparently rotten. 

 This joist was forced out from the other about 1 inch, and had 

 a horizontal split passing exactly along the line of the heads of 

 the three trenails, and completely separating it into two layers. 

 A small piece of the rotten wood underneath (about 6 inches by 

 2 inches by J inch) was broken off, and thrown about 4 feet into 

 the room on the floor to the north. An irregular patch of damp 

 plaster about 4 feet by 18 inches, which had formerly concealed 

 this rotten woodwork, was torn off, and most of it was (as in the 

 room above) thrown hard against the opposite north wall, to 

 which portions were still adhering. These portions are chiefly 

 higli up the wall, and near the floor above. Some larger pieces 

 were also spread over the intervening space. The wall where 

 this plaster was torn off was almost saturated with moisture, and 

 the plaster round the rent piece was quite wet and discoloured. 



There are no certain traces of the thunderbolt vi-ible on the 

 outside of the south wall, where, however, it mjst assuredly 

 must have been present. The ground at the foot showed no 

 signs of rending. There was a small lean-to outhouse nearly 

 below, the roof of which was damaged ; but 1 was led to under- 

 stand that this had been done before ; and as the place was 

 locked, and my time was limited, I did not go in ide it. At 

 the angle made by one of the side walls of this outhouse with 

 the main building, and not far from a point vertically below the 

 position of the end of the girder, was a wet pi;ce of ground 

 habitually used for emptying slops at ; and this seemed by no 

 means an unlikely place for the thunderbolt to have originated. 

 Here and there on the face of the dilapidated masonry some 

 rather new looking abrasions wee to be seen ; but not even just 

 abreast of the end of the girder could I detect for certain any 



traces of the explosion ; and no metal of any kind was visible. 

 In this connecti >n it may be mentioned that there were no 

 eaves-gutters, rain-water pipes, or metals of any sort on the out- 

 side of the house or on the roof. 



Perhaps the most noteworthy feature of this accident was the 

 complete absence of any sign of burning or charring at the rents 

 in the girder, joist, post, and rafter. The nails struck also 

 showed no symptoms of fusing ; and, for all the traces thit were 

 left by the stroke, it might have been quite unaccompanied by 

 heat. The work of the explosion seems to have taken alto- 

 gether the form of mechanical violence. The wood of the post, 

 rafter, and girder is sound, dry, old fir, and this would seem 

 peculiarly liable to be set on fire. 



The almost perpendicular bend that the course of the 

 stroke seems to have taken from the girder to the post is 

 also very curious. That the direction and force of the stroke 

 was upward appears to me a conclusion quite irresistible. I 

 have but little dntbt in my own mind, from the traces l.-ft by 

 the thunderbolt, that it sprang from the ground outside the 

 building, at or near the wet south wall ; passed up its outer face, 

 entered the building through the wall at the rotten wood, and 

 passed through or close to the joist and girder ; then, attracted 

 by the nails in the bottom of the post, it took a sudden turn 

 upward (for there were no other marks of its course in the first 

 floor room than those described), cleft right through the heart of 

 the post, altered its course obliquely to gouge out the lower part 

 of the rafter as far as the small nail, broke through the tiles, 

 knocked off the chimney- top, and thence rushed to join the 

 complementary force that had already started from the thunder- 

 cloud to meet it. A. Parnell 

 13, Windsor Terrace, Newcastle-on-Tyne, June 14 



The Soaring of Birds 



In Nature, vol. xxvii. p. 535, Lord Rayleigh gives what he 

 suggests as a possible explanation of the soaring of "pelicans 

 and other large birds in Assam " mentioned by Mr. S. E. Peal. 

 My own observations correspond so exactly with the theory ad- 

 vanced that I venture to give them for whatever they may be 

 worth. 



I have never indeed observed the flight of pelicans, but the 

 Indian kite, the turkey buzzard, and perhaps all vultures, have 

 the same habit of soaring in great circles. The sand/iill crane, 

 as it is commonly called in the United States, a large migratory 

 crane, possesses this characteristic in a most remarkable degree. 

 These birds will go soaring about for hours at an immense 

 height, never seeming to move a pinion except once in a great 

 while to steady themselves a little. They always move in irre- 

 gular circles at such times, and there is always a drifting with 

 the wind ; but at such a great distance above one it would be 

 impossible by mere ordinary observation to detect the obliquity 

 of the circles if it existed. 



A short time since, however, I had a fine opportunity of wit- 

 nessing the soaring of some kites ; the advantageous circum- 

 stances being that they were not far away, and that I saw them 

 commence when they were so low that there was little chance 

 of being mistaken in what I saw. I was sitting before an open 

 window one day about eleven o'clock. There was a gentle breeze 

 blowing from the south-east at the time. Pre ently my attention was 

 attracted by several kites over the village to the north-west. The 

 motions of two in particular I followed for some time. After 

 moving their wings to attain an elevation above the houses and 

 trets they began soaring, and continued upward in this manner 

 to a height of perhaps two thousand feet, apparently making no 

 exertion with their wings excep to steady themselves a little 

 occasionally. The method of accomplishing this was evidently 

 to circle away to leeward in a great curve which inclined down- 

 ward a little, thus acquiring considerable momentum ; then 

 turning toward the wind and adjusting the surfaces of the wings 

 to the proper angle, they would shoot upward to a point con- 

 siderably higher than the on 1 ! from which the circle began. By 

 the tiaie the momentum was exhausted the bird was circling 

 around again for another sweep to lee \ ard. 



There was considerable drifting with the wind, so that in 

 attaining an elevation of some two or three thou-and feet the 

 bird- had m ived away nearly a quarter of a mile. Their con- 

 sequent upward motion was in an irregular spiral, the highest 

 parts of the curves being on the windward side. 



Ongole, India, May 21 W. R. Manley 



