"On the 7th day of May, 1783, George Naylor, of Louth, in the County of Lincoln, well CHAP. II. borer, began to bore at the well in the Market-place, Boston, which had been sunk and bored to the depth of 186 feet from the surface, in 1747, by Thomas Partridge.

"The well was made about 6 feet in diameter at the top, 5 feet in diameter at the bottom, and 27 feet deep, and the earth prevented from falling in by a circular frame of wood, which goes from the surface of the earth to the depth of 21 feet and 6 inches, and is there supported by brick-work, laid on a bed of light coloured blue clay, which continues to the depth of 36 feet from the surface, where there is a bed of sand and gravel about 18 inches thick, and under it the same sort of blue clay as before, which continues to the depth of 48 feet from the surface. Below this there is a bed of dark coloured stone, like ragstone, about 6 inches thick, from under which George Naylor says that a salt spring issues. Beneath this layer of stone there is a bed of dark blue clay, which continues to the depth of 75 feet from the surface, where is a bed of stone of a lightish colour, about 6 inches thick, and under it a bed of dark blue clay, which continues to the depth of 114 feet from the surface, where there is a bed of stone of a brightish colour, about 8 inches thick, and under it a bed of gravel, about 6 inches thick, where George Naylor says there is another salt spring. Under the gravel there is a bed of dark coloured clay, resembling black lead, which continues to the depth of 174 feet from the surface, when it changes to a chalky clay, intermixed with small pebbles and flints, which continues about 3 inches, and then changes to the same kind of dark coloured clay as before; in which, after boring to the depth of 186 feet from the surface, he came to the solid earth, bored to in 1747, by the above mentioned Thomas Partridge. After boring in the same kind of clay to the depth of 210 feet from the surface, it changes to a light coloured one, which continues about six inches, and then changes dark again, and continues so to the depth of 342 feet from the surface, where there is a bed of shells and white coloured earth, about half an inch thick, and under it a light coloured earth, like that at 210 feet from the surface, and under it a bed of dark coloured clay. After continuing in that clay to the depth of 444 feet from the surface, George Naylor put down a tin pipe 56 yards in length, and 2 inches in diameter within, to prevent the gravel and stones from falling down and obstructing the rods; but, being too weak for that purpose, it separated into different lengths, and entirely prevented his boring, so that he was obliged to get the same pipes up again, which took 48 days; having got them up, and cleared the hole pretty well, he left off boring till he could procure stronger pipes.

"In July 1785, he put down twenty-one pipes of cast iron, which were cast at Chesterfield, in the County of Derby, each pipe being 24 inches in diameter within, half an inch thick, and, upon an average, 6 feet and an inch in length, they were affixed together with boxes and screws, and with a piece of soft leather between the top of each box and screw, to prevent them from breaking; the uppermost pipe is fastened to a plank, which lies upon the top of the brick-work.

"At the distance of 447 feet from the surface, there is a bed of dark coloured earth, mixed with chalk and gravel, which continues to the depth of 449 feet and 10 inches from the surface, where is a bed of dark coloured earth, without any chalk, with very little gravel, which continues to the depth of 454 feet and 7 inches from the surface, there it changed to dark coloured earth, mixed with chalk and gravel, which continues to the depth of 457 feet from the surface,

BOOK I.

and then changes to a light colour, and this continues to the depth of 462 feet and 4 inches from the surface, where it changes to a dark colour, and so continues to the depth of 470 feet and 3 inches from the surface. Here the ground changes to a dark coloured earth, mixt with chalk and gravel, which continues to the depth of 470 feet and 7 inches from the surface, where he came to a bed of stone, like ragstone, about 13 inches thick, which ground into powder with the wimble, and mixed with the earth. Under this bed of stone there is a dark coloured earth, without any chalk, and with but little gravel, which continues to the depth of 472 feet from the surface, when it changes something lighter, and continues so about 2 inches, where the earth appears to be mixed with chalk and gravel, and continues so for about an inch, when it changes to a black silt, having a great deal of light coloured sand.

"On September the 6th, 1785, George Naylor broke one of the screws belonging to his rods just above the top of the box, at the distance of between 92 and 93 yards from the surface, when the upper rod, having a circular head or ring 2 inches in diameter at the top, dropped down 40 yards through the iron pipes; which rods were got up again on the 15th of September by a spring. After trying several instruments to get up the lower part of the rods, to no effect, on the third day of October following he contrived a spiral instrument, about 2 feet long, with a catch at the top of it, to take the bottom of the uppermost box of the rods that were down; but the top of the rods having fallen several inches from the perpendicular, prevented the instrument from taking them between the first and second boxes; therefore the surveyor to the corporation, and the above-mentioned George Naylor, on the seventh day of October, contrived a spiral instrument, about 2 feet long, without any catch at the top, which George Naylor put down about 10 yards below the upper box, and there taking hold of the rods, raked them up to the top, and by that means brought them perpendicular, when he left them, and on the eighth day of October put down the instrument, invented before, by which he got hold of the rods a little below the top box, and brought them up. When the rods broke, George Naylor was boring in a dark coloured silt, intermixed with chalk and gravel, at the distance of 474 feet from the surface, which continued to the depth of 475 feet and 5 inches, when it changed to dark coloured wet silt, without any chalk, in which George Naylor bored to the depth of 478 feet and 8 inches from the surface. Here he imagined, by the easy turning of the wimble, that he had got into a spring of water, and gave over boring, to see if the water would rise in the pipes; when after keeping the water in the well below the top of the pipes for several days (by pumping,) the water in the pipes was found to rise about 6 feet per day upon an average; which only producing about seven pints, it was supposed there was no spring of water bored into, but the rise of water in the pipes was occasioned by the soccage only.

"On Monday the twenty-eighth of November, an iron bucket was affixed to the bottom of the rods, and let down the pipes, and filled with water at the depth of 85 yards from the surface; which water was salt and of a reddish colour. The bucket was again let down, and filled at the depth of 156 yards from the surface; that water was more salt than the first, and much of the same colour.

"The committee appointed by the corporation for superintending the business of sinking, having taken the whole of these circumstances into their consideration, and examining George Naylor, who did not account in a manner satisfactory to them, for the slow progress he had

lately made in boring, were of opinion, that it would be proper for the present to discontinue all operations in the well; they therefore directed the stage to be taken up, the mouth of the iron pipes to be carefully plugged, the well to be covered with oak plank, and the ground over it to be paved as before, all of which was accordingly done.”

"JAMES LIMBIRD, Surveyor to the Corporation."

CHAP. II.

"Boston, 8th of November, 1786."

"Sir,

"To the Right Honourable SIR JOSEPH BANKS, K. B.

"When you did me the honour in September last, of relating the proceedings which took place some years ago at Boston in Lincolnshire, for obtaining a supply of spring water for the use of that town, and was so good as to furnish me with copies of such particulars as have been preserved, of the sinking and borings which were made in the years 1747 and 1785, for ascertaining the strata under that town, as the grounds on which to give an opinion, respecting the probability of success, which might attend a further boring or sinking for water in the same place, I was anxious to complete the series of observations, which, under your kind protection, I had began on the order of the strata in the eastern and midland counties of England; it was also necessary, after I had by an examination of the strata of Lincolnshire, and of the neighbourhood of Boston in particular, ascertained that town to stand upon an alluvial covering to the thick assemblage of clay strata, known to some in Bedfordshire and other counties by the name of the clunch clay strata, that I should have an opportunity of referring to and comparing different accounts which I might have in London, of borings and sinkings in the clunch clay districts, before I ventured to give any written opinion on your questions, and I regret that the lateness of my return to town, with other unavoidable circumstances, have prevented my earlier attention to this subject.

"A variety of sinkings which I have seen, and careful examinations of the out-crop of the thick clunch clay which I have made, in different parts of England, enable me to conclude, after an examination of the section of the strata under Boston, which William Brand, Esquire, presented to you; that the first 37 feet beneath the surface there, consists of alluvial silt, clay, sand, and gravel, which though not regularly stratified, has in all probability beds of gravel or loose sand in it, sufficiently uniform and extensive, to form communications with the salt water in the river, or perhaps with that in the ocean, and thence to supply all the salt water, which is mentioned at 49 feet, 115 feet, 255 feet, and 468 feet of depths, all which came, I think, into the bore-hole by this means alone; for, as fresh water springs would have powerfully risen (for reasons which I shall give further on,) if any such had been penetrated by the augur, I may I think conclude, that the salt water which is said to have been drawn up from the two lower points (255 and 468 feet,) did not ouze into the bole-hole at those depths, but that the same was introduced there, from the alluvial springs above-mentioned, at the times of drawing up the augur with its charge, when a current of water would each time rush down to supply the space below the bit.

"There is a material distinction to be observed with regard to the term gravel, which has hitherto been overlooked by most practical well-diggers and borers, for they call the

BOOK I.

rubble of any loose rock or small pieces of stony substance, which their augurs or buckets bring up out of the earth, by the name of gravel, instead of confining that term to alluvial mixtures of broken and worn stones; in which sense, gravel has never I believe been found under any regular and undisturbed strata, but always upon such, in accidental heaps rather than in very extended strata.

"The ragstone mentioned at 48 feet, and the gravel at 115 feet 2 inches of depths, were as I conceive, only layers of the extraneous fossils or stony Nodulus called Ludius Helmontii, with which this clay abounds, and possibly these may, in this case, form such a continuous bed as to communicate with the sea, and produce salt springs, because, the layers of such nodules or clay balls, in the London clay strata, are known to produce small springs in several places, in the wells of Middlesex and Surrey.

"The chalk, small pebbles, and flints, if any such were really brought up, from the depth of 174 feet, could as I conceive, have come there only by falling down the hole from the alluvial gravel, first mentioned; after being detached by the friction and swagging of the rods, or by the nose of the auger in returning it into the hole; and this inconvenience seems to have been so often experienced, as to occasion the necessity, after they had bored to the depth of 444 feet, of putting down tin and afterwards iron pipes, to guide the upper part of the rods and prevent their action on the gravel and stones round the hole; yet I see no reason to conclude, that this precaution should absolutely prevent the further fall of small gravel and chalk stones from near the top, and that such might not still pass withoutside the tubes, and reach the bottom of the hole; and in this way I think it easy to account for the gravels and chalks which are mentioned at 449 feet 10 inches, 454 feet 7 inches, 456 feet 8 inches, 457 feet, 470 feet 7 inches, 472 feet, and 472 feet 3 inches of depths; and after all, without being able to inspect and examine the identical matters bored up, (which, as far as I could learn, are not preserved,) I see no evidence to contradict a supposition, that many of these, denominated gravel and chalk, were not in reality fragments and chippings of Ludus Helmontii or of clunch, the borings of either of which might too much resemble chalk to be easily distinguished therefrom.

"I have, Sir, been thus particular respecting the borings by Thomas Partridge and George Naylor, because your question as to the probable distance which must be further bored or sunk before a spring of water will be found, entirely depends for an answer upon ascertaining the fact, whether alluvial gravel had really ceased after 37 feet of depth, and the clunch strata commenced. I shall therefore proceed to mention some other circumstances, which have conduced towards fixing my opinion, that the borings, after the first 373 feet were actually in the clunch clay; these are: First, the ascertained fact, that this assemblage of clay strata, or some of them, actually descend at the edge of the northern border of the fens, and pass under them all the way from Bolingbroke to Tattershall; the same having been penetrated, and their proper extraneous fossils exposed, in various parts of the new catch-water drain. Secondly, if you do me the honour to compare my account of the clay strata in Hareby Sand-hill, near Bolingbroke, with the Boston borings, considering the first clay of 15 feet 10 inches thick, as the same as that of which 10 feet remains under the 37 feet of alluvial deposits at Boston, you, will, I think, Sir, perceive all the marks of identity which can be expected in two parts of the same stratum, at the distance of 15 miles from each other; the "dark blue clay resem

bling black lead," in the Boston borings, agreeing as well as could be expected, with the dark CHAP. II. bituminated clays, occurring in the last 68 feet of my levellings near Bolingbroke. Thirdly, Mr. William Hobson, in the last year, employed persons to bore in search of coal upon the farm in Raithby, in his occupation, which, at the time, when I visited the spot and received information from him in writing on the subject, had extended to the depth of 312 feet, without meeting with any spring of water, and the only substances reported by his borers, to have been penetrated, except clay, were such as coal borers, in various parts of England, have hitherto denominated coal slate, &c. but which, on sinking expensive shafts, have uniformly proved to be bituminated-shall or earth, (of which pretended coal, large quantities might be dug above ground, near the west end of Bolingbroke, were it good for any thing,) shall, clunch, or other well-known products of these strata.

"If this point be established, viz. that 441 feet 2 inches of the lower part of the Boston borings were in the clunch clay strata, it will follow, from the uniform and well established laws of the stratification with which you are so well acquainted, that the next stratum beneath this in the series, is the lime stone, (called by some the Bedford lime stone,) which appears upon the surface, near the town of Sleaford, the springs from which supply a large portion of the water in the navigable rivulet or canal, below that town.

"This Bedford lime stone will be found stretching away on the surface southward, from Sleaford to the neighbourhood of Deeping, dipping pretty uniformly eastward, and always entering under the clunch clay, which is the pan or sub-stratum, probably of all the line of fens in Lincolnshire, between Crowland town and the junction of the Ancholm with the Humber river.

"That the boring at Boston, or rather the sinking which I should recommend, if persevered in, would reach this lime stone, and supply a most plentiful spring of excellent water, I cannot have the least doubt; and I am happy in being able to refer to a case in Buckinghamshire, which though so distant, is exactly in point. Early in the spring of 1802, when my friend Mr. Bevan the engineer and myself were receiving practical instructions from Mr. William Smith, relative to his discoveries on the stratification, in a tour undertaken for that purpose, we accidentally met with the Reverend Mr. Le Mesurer, rector of Newton-Longville, near Fenny-Stratford, who related his having undertook to sink a well, at his parsonage house, within a mile or two of which, no good and plentiful springs of water were known, but finding clay only at the depth of more than 100 feet, was about to abandon the design; Mr. Smith on looking into his map of the strata, pointed out to us, that Newton-Longville stood upon some part of the clunch clay strata, and that the Bedford lime stone appeared in the Ouse river below Buckingham, distant about eight miles in a north-west direction, and he assured Mr. L. that if he would but persevere, to which no serious obstacles would present themselves, because all his sinkings would be in dry clay, he would certainly reach this lime stone, and have plenty of good water, rising very near to the surface; Mr. L. accordingly did persevere in sinking and bricking his well, and at 235 feet beneath the surface, (the first 80 feet of which were in alluvial clay with chalk and flints, &c. similar exactly to what I have uniformly found on your estate at Revesby, and in the bottoms of many of your fen drains ;) the upper lime stone rock, (8 feet thick) was reached and found to be so closely enveloped in strong blue clay, as to produce not more than 9 feet of water in the well in the course