From Symons's monthly Meteorological Magazine
WHIRLWIND AT BALDOCK, HERTFORDSHIRE.
On the morning of June 15th the following paragraph appeared in The Times:-
Mr. E. Smith writes to us from Baldock, Hertfordshire :- "Some of your readers may be interested to know that this place was visited during the afternoon of Saturday by a wind of extraordinary strength and fury for so inland a situation. About 1 o'clock a brief thunderstorm, culminating in one loud cracking peal, passed over the town from the south-west, and shortly afterwards, and in its wake, a very low and gloomy cloud was seen to be approaching with remarkable velocity. The cloud appeared to be of a hollow or perhaps spiral shape, horizontally inclined, with a huge whirling tail; indeed was so monstrous and furious in its aspect as to be positively tenible. Immediately the air near it was observed to be filled with branches and leaves of trees, slates, stones, dust, &c. The phenomenon came on with awful energy across Mr. Thomas Pryor's park and the .upper part of High-street, close to the ground, and in about a minute more was passed and gone, leaving behind it a sulphurous smell. Then it was discovered that not only had the wind dismembered and uprooted several large trees in its course, but had thrown down the greater portion of an extensive block of modern and valuable maltings belonging to Mr. Pryor, and situated in a somewhat sheltered corner in the rear of his park, causing a loss which I am sorry to say £1000 will barely cover. The whirlwind seems to have been only a few yards in diameter, and its course, which was somewhat circular, from S.W. to N.E. [The evidence of the circular motion seems very slight.] As lightning itself so often does, the storm showed in its effects a remarkable caprice; but happily no injuries to life or limb occurred, although one or two persons had a narrow escape."
The Times 15th June 1875
Knowing the locality and some of the gentlemen mentioned, we were satisfied of the authenticity of the statement, and therefore started at once for Baldock, and spent a day in thoroughly examining the effects of the whirlwind. As we desire to devote our space chiefly to the consideration of the manner in which these effects were produced, we avail ourselves, as far as possible, of descriptions of them by other persons. We, therefore, next reprint the account given in the Hertfordshire Express, appending to it, as we have done to Mr. Smith's, foot notes, critical and explanatory. On the whole, both accounts are very good
EXTRAORDINARY STORM OF WIND AT BALDOCK.
A hurricane, the like of which is not remembered by the oldest inhabitant, passed over the town of Baldock on Saturday last, causing, in its impetuous and resistless course, a very considerable amount of damage. The cyclone approached Baldock from the south-west, and its passage is marked in a meadow of Mr. Lowe's by the branches torn off the trees and strewn in all directions over the meadow. Next, the maltings, belonging to Mr. Thomas Pryor, of the Park, Baldock, in the occupation of Mr. Page, standing on ground adjoining the farm homestead of Mr. Lowe, fell a prey to its fury. These maltings are of modern construction, having been built about fourteen years ago on the site of maltings which were then destroyed by fire. The buildings of which these maltings form part consist of a long malt warehouse and drying kilns, running from east to west, probably about 200 feet in extent. From this building three maltings branch out at right angles from south to north, thus presenting their broad side to the whole force of the storm, and sustaining, as the sequel will allow, nearly the whole of the damage. The malting which was first injured is a building 150 feet long, by 44 feet broad. The damage to this structure appears to have been caused by the pressure of the wind on the outside of the roof, for all the windows were shut and the appearance the roof presented just after the occurrence seems to point to this conclusion.
The centre of the roof for, perhaps, 100 feet was crushed inwards, and the walls above the ground floor were pushed over and lay on the floor above. Half the roof rested on the upper floor, while the other half with the wall on the east side were precipitated and lying, at the time of our visit, in a heap of ruins in the intervening space between this and the next building. The barley loft next Mr. Lowe's farm has resisted the storm and is still standing, but the wind, by its pressure on the roof, has swayed the end wall 80 much that it is doubtful whether the upper portion will not have to be rebuilt.
The lower floor has sustained no injury. The centre malting was of considerable dimensions, about 100 feet long by 50 broad. The damage done to this is nearly entirely confined to the roof. It appears that one of the maltsters was working in this building in the morning, and consequently the side shutters were all open. The wind, entering by these apertures, separated the east half of the roof from the other half longitudinally and quite lifted it with the boards and rafters from the main principals and framework. These latter, except one, remain in position and, with the western half of the roof, are almost intact. It is stated that it took 30 tons of slates to cover the rafters, so that the wind must have had sufficient force to lift fifteen tons besides the rafters and boarding, and to turn them completely over into the yard below. The roof of the drying kiln, which joins the end of this malting, is tiled, and a portion of it appears to have been lifted up simultaneously with that of the malting, and the two coming in contact fell on to the upper stage of the malting with so much force as to break one of the principals -a beam 11 inches deep by 6 inches thick - and the debris, probably several tons in weight, remained, at the time of our visit, a confused heap of tiles, slates, rafters, beams, and boards. The covering to the kiln technically termed a mushroom, or kimberlo, with the iron work which supported it, was lifted out of its place by the wind and deposited on this heap. The general appearance of the interior of this malting bears out the theory that the force of the storm was expended internally and that the roof facing towards Hitchin was strong enough to resist the outside pressure.
The malting by the side of the road leading to Willian has suffered much in the same way as the one first described. The storm has crushed in the roof from the outside, carrying inwards the west wall and forcing out a portion of the upper wall by the roadside and half the roof to the ground beneath. Some of the principals and framing of this roof were forced through and embedded in the outer wall.
It was the custom for a brass band to practise here, and the forms where the musicians sat and the lamps they had last used were there, after the storm had spent its fury on the building, uninjured. The road was almost impassable for a time from the accumulation of rafters, boards, bricks, and tiles; the trees in the park on the other side, besides being damaged and torn about by the raging of the wind, had their branches filled with slates and broken rafters; and in the meadow beyond a large piece of roof had fallen, giving evidence of the great violence and power of the storm. The buildings, viewed from the top of one of the dismantled maltings, presented a most remarkable sight. The roofs of the outside maltings had been torn asunder for, perhaps, 80 feet of their length, and at each end the jagged ends of boards and protruding beams and rafters gave the idea that a terrible railway accident might have happened there. The ruin was almost as complete as if a fire had again occurred, but without the consolation that follows from a fire insurance. It was fortunate that the malt lofts, which stood end ways to the storm, resisted its force, for a considerable quantity of malt was in store, and the loss would have been much more serious had the buildings containing it been damaged like the maltings. As it was, scarcely any malt was lost or damaged. It is fortunate also that the catastrophe happened at a time of year when no malting was being carried on. If the storm had occurred in the autumn or winter probably Mr. Page would have sustained great inconvenience and loss.
The trees in the park on the other side of the road were torn and large arms were twisted off them, but at this point the whirlwind appears to have risen, and no more damage was done until it reached the other side of Baldock, where a tree was torn up by the roots and other trees were much damaged.
Mr. T. B. Latchmore, of Hitchin, has photographed the damaged maltings, and no doubt the vivid representation of the catastrophe will ensure a large sale.
Hertfordshire Express, June 19th.
We must also here insert a letter with which we have been favoured by Mr. Lucas, and a few scraps of miscellaneous information :-
Sir, -I hope your expedition on Tuesday last to the scene of devastation at .Baldock was not unproductive. Since I saw you I have learned a few details of the course of the storm. At Little Offley (where I have established a rain gauge), 3 miles S.W., in addition to the wind which damaged trees very much, there was a most extraordinary hailstorm, many hailstones being considerably over an inch across, and being star-shaped. Out of curiosity Mr. Lawson's bailiff weighed some of them, and 123 hailstones weighed ¾lb; this was at Lilly, one mile S. W. of Little Offley. The hurricane crossed the Bedford-road half-a-mile N. of Hitchin, damaging a house, then did great damage in what we call "Fishpond Closes," went on to Grove Mill, damaging the poplar trees there, and then over an open country - I presume, to Baldock - on to Royston, where it appears to have done considerable damage.
Yours faithfully, W. LUCAS.
Hitchin, 21st June, 1875.
HITCHIN.-TERRIFIC STORM.-About twenty minutes to two on Saturday afternoon a westerly hurricane of unusual violence swept over a portion of this town and district. The beautiful trees in that portion of the place known as the Fishponds were much damaged. Huge boughs were torn off, tossed up in the air to a considerable height, and carried a great distance. No damage was done to house property, beyond the carrying away of a few tiles and chimney pots.
HlTCHIN.-On Saturday afternoon, about twenty minutes to two, a westerly hurricane of terrific fury, passed over a portion of this town. Near the Union a few tiles were taken off the roofs of cottages, and some slight damage was done to :Mr. Richardson's back premises in the Bedford-road. The trees in the Fishponds suffered much, the tops of many being wrenched off, and tossed high in the air and then carried some distance. Passing in the direction of Grove Mill, the trees easily succumbed to the wind, and the tall poplars at the latter place were much damaged.
Between Letchworth and Baldock a man had been at work on a straw stack, but at the time of the hurricane he was fortunately away, for when he returned he found the stack scattered all over the field. Another man was violently thrown against a gate, to which he had to cling until the hurricane passed.
At Baldock there was a very serious destruction of property, and it seems miraculous that there was no loss of life. Mr. R. Page's malting, situate near Mr. Lowe's farm, was almost entirely unroofed. The building covers more than an acre of ground and was substantially built, being only about 15 years old. It consisted of three buildings 155 ft. long and 45 ft. wide, running parallel, and joined at one end. In the end storehouses was 500 quarters of malt, but the other houses were undergoing a thorough cleansing. On Saturday afternoon no one was at work upon the premises, or there must have been loss of life. An eye witness says, about twenty minutes to two, whilst near the maltings, he heard a noise as of thunder, accompanied by the snapping of trees, and on looking round he saw the trees falling a prey to the furious wind. Quickly it came on and caught the maltings broadside. All the windows were open, and the wind entering there, the roof was lifted into the yard between the next block of buildings. The heavy rafters were torn out, brickwork gave way, and the slates were carried a long distance. The two other buildings shared the same fate, the roof of the outside one being deposited in a slanting position into the adjoining road. The air was filled with debris, and the trees in the beautiful avenue opposite, next fell before the rapacious wind, completely blocking up the roadway. The property belongs to Mr. Thomas Pryor, and is in the occupation of Mr. R. Page. It is estimated that the damage done will exceed a thousand pounds. As a proof of the fury of the hurricane, we may mention that slates from the roof were carried some distance, and then deeply driven into the trunks of the trees. Some of the wood was carried a distance of 500 yards.
From Royston a correspondent writes to say that about 15 cwt. of lead on the roof of the church was rolled up "like a pipe light." A very high chimney stack at the Priory, the residence of Joseph Phillips, Esq., was blown on to the roof, breaking through from gable to eaves, but fortunately no one was hurt. A very fine chestnut tree, belonging to the Rev. Medway, had a large arm blown off, which was carried a distance of thirty or forty yards.
Herts. and S. Beds. Journal.
We had intended to give a map of the path of the whirlwind, but the country traversed presented so few objects which could be affected, that the injury, except at Baldock, is very slight, while the length of the track is quite 19 miles. The following are the details of the traces above recorded. Assumed line of centre of whirlwind extends from 4 miles W.S.W. of Hitchin to Royston. Its direction was from W. 28Â° S. to E. 28Â° N., or, roughly, from W.S.W. to E.N.E.
The first trace is at Lilley (lat. 51° 56' N.) Ion. 0° 23' W,), distance from assumed path (which commences here) 0.7 mile N. At Little Offiey (Ii miles from commencement of track) damage was done 0.6 miles N. of path. Hitchin Fishponds are 4'3 miles along the path, and absolutely on it. Grove Mill is 4.9 miles along and 0.1 mile N. of path. The scattered hayrick, in Letchworth parish, was 7 miles along and 0.1 mile N. of path. The maltings at Baldock are 8.7 miles along and absolutely on the path, but the two trees on the other side of Baldock, and 9.3 miles along, are 0.2 mile (350 yards) S. of the path. Lastly, Royston forms the extremity of the path. The close agreement of all these cases with a rigorously straight line is remarkable.
In the next place we must say a few words respecting the illustrations, premising that nothing but Latchmore's large photographs would give anyone an idea of the wreck at Baldock. The length of these remarks is much reduced by the accuracy of the description quoted above from the Hertfordshire Express, which we need only supplement. Each building consisted of two floors, the upper of which had no ceiling but the roof. The end of each range is cut off from the long malting floor by a vertical wall, and none of these end buildings was unroofed. The most westerly range, which was first struck, is represented in the engraving.
The whole of this roof (A) was either lifted and dropped, or else pushed about 4 ft. eastwards, the walls from the level of the upper floor to the eaves of the roof were thrown over eastwards, the west one falling on to the floor just mentioned, and the east wall of course falling outwards into the yard. From the fact that the bricks of the west wall were not in the least disarrangl3d (they lay quite ready for rebuilding), and that the slates on t,hat side were almost free from injury, we cannot believe that the roof was pushed bodily eastwards by a westerly wind. It is well known that the passage of a whirlwind over a pond will empty it (e.g. see Met. Mag., vol. viii., p. 168); now this means that it will raise many tons of water, for 36 cubic feet of water weigh a ton, therefore a pond 20 ft. in diameter, and 2 feet deep, would contain nearly 20 tons of water. Again, from what we know of the rate of diminution of pressure in the greater whirlwinds which we call cyclones, it is surely not unreasonable to assume that in the very limited area and high intensity of a true whirlwind there is a diminution of pressure of half an inch of mercury. If so, as half an inch of mercury represents a quarter of a pound on each square inch of surface, or 361bs. on each square foot, we should have the diminution over the damaged part of this building, say 120 ft. by 40 ft, or 4,800 feet = (4800 x 36 =) 172800 lbs. or 77 tons, whereas the slates and timber probably only weighed about half that amount.
Without wishing in any way to dogmatize upon the subject, we must express our belief that the passage of the whirlwind produced such a diminution of pressure as caused the air in the building to expand, and to lift the roof, and that the motion of translation of the whirlwind caused it to be dropped about 4 ft. further eastwards than its original position.
The damage to the second range of buildings (B), though quite different to that done to the first, is capable of similar explanation-in fact, it is remarked by the reporter that "the force of the storm was expended internally." Both walls, the principals, and nearly every slate on the side from which the storm came, were undisturbed; but of the eastern slope of the roof not a vestige remained - rafters, boards, and slates had all gone, as cleanly and neatly as if they had been purposely removed.
The third range (C) suffered very much in the same manner as the first, but there was one feature in which difference existed-the east wall was not thrown into the lane, as it should have been to render the similarity perfect, and several of the principals had sawn their way (no other term so well expresses the appearance) through two and even three courses of bricks. We do not know why this difference occurred, there are obviously two explanations, but perhaps neither is correct. It may have been that the wall, being the outer one of the premises, was built with better materials than the others, but the whole of the buildings were very substantial - otherwise, for instance, the upper floor of the first building could not have supported the roof in the position shown in the engraving. Another explanation is that perhaps the whirlwind was rising rapidly when it reached the last range of buildings, and therefore exerted lifting rather than tractional power.
Lastly, there remains the transverse building (D), and its almost perfect immunity to be considered. Here, again, two explanations offer themselves. It may have been that the whirlwind did not pass over it, or it may have been - and we incline to the opinion - that inasmuch as the building was full of malt far above the eaves, and nearly to the ridge, there was not enough air inside to produce sufficient expansive force to lift the roof.
Looking at the slates sticking in the trees like so many axe heads, it would be ridiculous to deny that there was a very strong wind; but the impression left upon our mind is that the prime cause of the disaster was the expansion of the air inside the large malting floors, consequent upon the sudden passage over them of a whirlwind, in the centre of which the atmospheric pressure was greatly diminished.
We must not conclude without expressing our thanks to Mr. Page, the occupier, for the courteous assistance which he has given us, both when inspecting the ruins and subsequently.
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