dies has failed of giving relief, the other ought to be tried: for as the above white calculus, which yielded a little to the solution of soap, resisted lime-water; so there may perhaps be others, that are readily dissolved by lime-water, but little affected by soap.

Dr. Springsfeld's experiments with lime-water are not just; for in several calculi Dr. Whytt found the dissolving power of oystershell lime-water above 8 times. greater than he makes it.

Observations on the Lithontriptic Virtue of the Carlsbad Waters, Lime-water, and Soap. By Robert Whytt, M. D. F. R. S. p. 386.

From the experiments related in Dr. Springsfeld's Commentatio de Prærogativa Thermarum Carolinarum, &c. it appears (says Dr. W.) that these waters are not only possessed of a very extraordinary power of dissolving the stone, but that in this respect they greatly exceed lime-water.

(A) Thus, Dr. Springsfeld having infused, for 14 days, in a heat of 96 degrees of Fahrenheit's scale, 3 pieces of the same calculus, each weighing 30 grains, in eggshell lime-water, the Carlsbad water, and in the urine of one who daily drank this last water, renewing these several menstruums every day, he found, on the 15th day, that the calculus in the lime-water had lost 1 gr. the calculus in the Carlsbad water 6 grs. and that in urine 5 grs.

(B) Again, having divided another calculus into 4 parts, each of which was reduced to 80 grs. he put the first in oystershell lime-water, the 2d in Carlsbad water, and the 3d in the urine of a person who drank this water. After 20 days, during which time the menstruums were renewed every day, and kept in a heat of 96 degrees, the dried calculi had lost of their weight as follows: the first 3 grs. the second 18 grs. and the third 14 grs.

Although Dr. W. made no doubt that Dr. Springsfeld, who appeared to be a man of candour, as well as learning, had faithfully related the event of the experiments, which he made; yet either the lime-water he used must have been very weak, or some other mistake must have happened in his experiments: for in all the numerous trials Dr. W. made, about 15 years before, of lime-water, as a solvent for the stone, Dr. W. always found its dissolving power much greater than it appeared in Dr. Springfeld's experiments. And as in these trials different urinary stones were used, it can scarcely be imagined, that it was owing to the peculiar hardness of Dr. Springsfeld's calculi, that the lime-water made so little impression on them. However, to be still further satisfied of this matter, Dr. W. made the following experiments.

1. He put a piece of a very hard calculus, x, weighing 80 grains, in oystershell lime-water, renewing the lime-water every day, and keeping it in a heat between 90 and 106 degrees of Fahrenheit's scale. After 20 days he took out the calcuus; and having set it by for some days, till it was become quite dry, he brushed Y

VOL. XI.

away all the rotten part of it, which was reduced to a kind of chalky powder, and found that the undissolved part of it weighed 57 grs.-2. At the same time a piece of another calculus, z, weighing 15 grs. was, after a like infusion of 29 days in oystershell lime-water, reduced to 10 grs.-3. He put a piece of z, weighing 14 grs. in a solution of an oz. of the internal part of Spanish soap in 9 ounces of water, and every 3d day renewed the solution, which was kept in a heat of about 60 degrees. After 14 days he found the undissolved part not to exceed 11 grs.-4. A piece of a white chalky calculus, y, weighing 30 grs. had nearly 4 grs. of its substance dissolved, by being 14 days infused as above in a solution of soap.

From No 1 above, compared with Dr. Springsfeld's exper. (B,) it appeared, that the dissolving power of oystershell lime-water, was to that of the Carlsbad water, as 23 to 18; supposing the calculi used in these experiments to have been equally easy to dissolve.-N° 3, compared with Dr. Springsfeld's exper. (A) showed, that the dissolving power of a solution of the inner part of Spanish soap, in a heat of 60 degrees, was to that of the Carlsbad water in a heat of 96 degrees, as 15 to 14.-From N° 4, compared with (A) the dissolving power of soap was to that of the Carlsbad water, only as 4 to 6; but it was probable, that had the solution of soap been kept in a heat of 96 degrees, its dissolving power would, even in this experiment, have nearly equalled that of the Carlsbad water. It should perhaps be observed, that a piece of the white chalky calculus of N° 4 was not in the smallest degree dissolved by lying in lime-water 20 days.

5. In exper. 19 of his essay on the virtue of lime-water, a piece of a calculus, b, weighing 31 grs. lost 7 grs. by being infused 36 hours, in a heat of above 100 degrees, in very strong oystershell lime-water. And in the same water, of a moderate strength, another piece of b lost, in the same time, 5 grs.-In this last experiment, the lithontriptic virtue of lime-water appeared to be stronger than in N° 1 and 2 above; and greatly exceeded that of the Carlsbad water in Dr. Springsfeld's exper. (A) and (B).

But although, from what had been said, it appeared not only that lime-water, but also a solution of soap, dissolved the stone in close vessels as fast, nay faster, than the therma Carolina; yet these last waters, when the calculi were so placed in open vessels, that the water from the fountain might constantly flow along them, effected a much quicker dissolution than lime-water, or even soaplee, or indeed any known menstruum, except perhaps strong spirit of nitre: for, in the first experiment made by Dr. Springsfeld, a calculus of 2 and oz. was, in this manner, quite dissolved in 6 days. From this experiment, compared with that of Dr. Springsfeld mentioned above (B), it will be found, on calculation, that the dissolving power of the Carlsbad water, when it is allowed to flow constantly from the fountain along the stone, is nearly 39 times greater than

when it is only poured fresh on the calculus once a day. What may have been the reason of this surprizing difference of the lithontriptic power of the Carlsbad water in these different circumstances, he pretends not to say. He thought it could scarcely be accounted for from the gentle motion of the water along the surface of the calculus. Was it then owing to some very volatile active part, which the water quickly lost, after being taken from the fountain?

But how great soever the dissolving power of the Carlsbad waters might be, when they issued from the bowels of the earth, yet that they did not communicate a much greater dissolving power to the urine, than lime-water, would appear from comparing the 2 following experiments.-In Dr. Springsfeld's exper. (A) above, the urine of a person, who drank the Carlsbad waters, reduced, in 14 days, a piece of calculus, weighing 30 grs. to 25 grs. And in an experiment made by Dr. Newcome, now Lord Bishop of Llandaff, who drank 4 English pints of oystershell lime-water daily, his Lordship's urine reduced, in 4 months, piece of calculus, weighing 31 grs. to 3 small bits, weighing in all 6 grs. Whence it followed, that the dissolving power of his Lordship's urine must have been to the dissolving power of the urine of the person who drank the Carlsbad waters, nearly as 35 to 65. But if we consider, that the calculus infused in the trine of the person who drank the Carlsbad waters was kept always in a heat of 96 degrees, while in Dr. Newcome's experiment, which was made during part of the autumn and winter, no artificial heat was used, it will appear probable, that the dissolving power of his Lordship's urine was little inferior to that of the person who drank the Carlsbad waters; for lime-water, in a heat of 96 degrees, dissolves the calculus at least twice as fast, as in the common heat of the air in winter. Further, if it be attended to, that the quantity of Carlsbad waters drank every day before dinner is from 6 to 8 lb. while his Lordship only drank 4lb. of lime-water in 24 hours, it will follow, that whatever the different dissolving powers of the lime-water and Carlsbad waters may be out of the body, yet the former seemed, in proportion to the quantity drank, to communicate at least an equal dissolving power to the urine.

But without presuming to decide certainly, as to the comparative virtue of the Carlsbad waters and lime-water, he concluded with observing, that though the Carlsbad waters are less disagreeable to the taste, and may be drank in larger quantity, than lime-water, yet this last may be drank equally good in all places, and at all seasons of the year; which is not the case with the Carlsbad waters. An Instance of the Electrical Virtue in the Cure of a Palsy. By Mr. Patrick - Brydone, Minister of Coldingham. p. 392.

Eliz. Foster,* aged 33, in poor circumstances, unmarried, about 15 years * Of the parish of Coldingham, where she had lived all her life. Her father had died of the palsy seven years before.-Orig.

before was seized with a violent nervous fever, accompanied with an asthma, and was so ill, that her life was despaired of. She recovered however from the violence of her distemper, but the sad effects of it remained. For from this time she continued in a weakly state of health till July, 1755, when she was again taken ill of the same kind of fever; and after it went off she was troubled with worse nervous symptoms than ever, ending at last in a paralytic disorder, which sometimes affected the arm, sometimes the leg, of the left side; in such a manner as that these parts, though deprived of all motion for the time, yet still retained their sensibility. In this condition she remained till the spring 1756, when unexpectedly she got much better; but not so far as to get quite rid of her paralytic complaints; which in cold weather seldom failed to produce a numbness, trembling, sensation of cold, and a loss of motion in the left side. About the end of August, her symptoms gradually increased, and in a short time she lost all sensation in her left side. In this state she continued throughout last winter, with the addition of some new complaints; her head shook; her tongue faltered; her left eye became so dim, that she could not distinguish colours with it; and she was often seized with such a universal coldness and insensibility, that those who saw her at such times scarcely knew whether she was dead or alive.

While the woman was in this miserable condition, observing that she had some intermissions, during which she could converse and use her right leg and arm, in one of those intervals Mr. B. proposed trying to relieve her by the power of electricity. With this view, he got her supported in such a manner as to receive the shocks standing, holding the phial in her right hand, while the left was made to touch the gun-barrel. After receiving several very severe shocks, she found herself in better spirits than usual; said she felt a heat, and a pricking pain, in her left thigh and leg, which gradually spread over all that side; and after undergoing the operation for a few minutes longer, she cried out with great joy, that she felt her foot on the ground. The electrical machine producing such extraordinary effects, the action was continued; and that day the woman patiently submitted to receive above 200 shocks from it. The consequence was, that the shaking of her head gradually decreased, till it entirely ceased; that she was able at last to stand without any support; and on leaving the room quite forgot one of her crutches, and walked to the kitchen with very little assistance from the other. That night she continued to be well, and slept better than she had done for several months before, only about midnight she was seized with a faintishness, and took notice of a strong sulphureous taste in her mouth; but both faintness and that taste went off, on drinking a little water. Next day, being electrified as before, her strength sensibly increased during the operation, and when that was over she walked easily with a stick, and could lift several pounds weight with her left hand, which had been so long paralytic before. The

experiment was repeated on the 3d day; by which time she had received in all upwards of 600 severe shocks. She then telling them that she had as much power in the side that had been affected as in the other, they thought it unnecessary to proceed further, as the electricity had already, to all appearance, produced a complete cure. And indeed the patient continued to be well till the Sunday following, viz. about 3 days after the last operation; but on going that day to church, she probably took cold; for on Monday she complained of a numbness in her left hand and foot; but on being again electrified every symptom vanished, and she was perfectly well ever afterwards.*

Ll. Of some Fossil Fruits, and other Bodies, found in the Island of Shepey. By James Parsons, M. D., F. R. S. p. 396.

It will not be amiss to give a short detail of such bodies as are capable of either being petrified themselves, or of leaving their impressions in stony matter. By being petrified, is meant being impregnated with, stony, pyritical, or any other metalline or sparry matter; for there are innumerable specimens, where all these are apparent.

Testaceous and Crustaceous Animals.-The shelly matter of these is of so compact and dry a nature, that they will endure for ages: and if in a soil or bed where moisture has access, they will receive stony matter into their pores, and become ponderous in proportion to the quantity imbibed. If in a dry place, they will remain fair and sharp, suffering very little change by any length of time; while the flesh of these, being subject to putrefaction, is soon destroyed; and yet some of these may be replaced in due form by stony particles.

Wood. The kinds of wood found fossil are of very different texture; and this too is according to the places where they are deposited. Some are seen so highly impregnated with a fine stony and pyritical matter, as to bear a polish like a pebble; some, though quite reduced to stone, yet preserving the fibrous appearance of the original state; and some which is found in boggy bottoms, being not at all changed, except in colour: this is called bog oak, or bog deal, well known to country people in many places of these three kingdoms, who light themselves about their business with slips of this wood, cut on purpose instead of candles, as it burns with a clear and durable flame. It is remarkable, that though oak or fir shall lie ages immersed in water under-ground, it shall not putrefy, but acquire such sulphureous particles by lying in steep in the bogwater, as to qualify it for this use. Other wood, deposited in marly ground, is found incrusted over, trunk and branches, with a white crust, the wood remain

* This account was attested by the patient herself, and by the minister of Coldingham, in Berwickshire, where she lived. The truth of the above statement was also further corroborated by a letter from Dr. Whytt to Dr. Pringle.