" ACCORDING to Dr. Percival, Matlock water is grateful to the palate, and of an agreeable warmth, but exhibits no marks of any mineral spirit, either by its taste, sparkling appearance in the glass, or with syrup of violets. It is very slightly impregnated with selenite or other earthly salts, and of this its comparative levity affords also a further proof. It weighs on\y four grains in a pint heavier than distilled water. The precipitation of a grey powder, by adding a solution of silver in aqua fortis to the water, renders it probable that a small portion of sea salt is contained in it.

" Dr. Pearson says it has been reported to contain in a gallon of water forty grains of sediment, which is called nitre, alkaline earth, and sea salt. He observes himself, that it is impregnated with rather more fixed air than Buxton water, and that a pint weighs eight grains heavier than distilled water.

" I found that with syrup of violets the water at the spring upon the hill was turned greenish ; and therefore conclude, that it conclude that it contains a small quantity of fossil alkali. Upon the addition of galls and Prussian lixivium no change whatever was produced. That it contains calcarious earth will not admit of a doubt. This is manifest from the copious precipitate which takes place upon adding the fixed vegetable alkali, but more especially from the large quantity of this substance which is deposited in the kettles and other vessels, in which it is usually boiled. On pouring vitriolic acid on a small portion of sediment, collected in this manner, a very strong effervescence ensued.

" In respect to the temperature of the Matlock water, it is found that Farenheit's thermometer rises in it to 69 degrees at the spring, and 68 in the bath.

" Dr. Percival observes, that Bristol and Matlock waters appear to resemble each other, both in their chemical and medicinal qualities In hectic cases, hæmoptoes, the diabetes, and other disorders, in which the circulation of the blood is quick and irregular, he apprehends Matlock water on some accounts claims the preference to that of Bristol. For as it is not sensibly impregnated with a mineral spirit, it should seem less disposed to quicken the pulse, and may therefore be drank in larger quantity.

" Since Dr Percival made his observations on the impregnation and uses of Matlock water, Dr. Francis Armstrong, physician at Uppingham, in the county of Rutland, has addressed the public on the same subject. He says, I have taken great pains to examine particularly into the properties of Matlock springs, and may with truth assert, that they are of the same nature with the Bristol water, equal in some cases, and preferable in many. Nor do I think that the air of Matlock is in the least unfavourable to consumptive patients, where the lungs are not injured in such a manner, as to render a recovery very doubtful, either from the use of medicine or water ; nor have I in my whole practice, had the least complaint of this inconvenience from any of my patients.

" I ordered a most amiable lady last year to drink the Matlock waters, in a confirmed phthisis pulmonalis, and in such a situation, that I must own I never expected to see her return. Being greatly interested in her preservation, I gave her full directions how to proceed. With much difficulty she reached the place. The company in a very uncandid manner, cried out, " What a cruel physician, to send the lady so far from home to die !" I saw the lady but three days before she left home, otherwise she would have visited Matlock much sooner. She strictly persevered in the rules laid down, and in a fortnight was able to dine in public; in six weeks was perfectly recovered, having got rid of her cough, and being greatly increased in her muscular habit. I visited her on her return, and had I not been perfectly acquainted with her before, I should not have known her. She has continued well ever since, and I hope will for many years, as a blessing to her young family, and a comfort to the best of husbands.

" I hope I shall be excused reciting this case, it being one, amongst many, in which I have experienced the good effects of this water; and indeed patients, whom I have sent to Bristol, and who have returned, benefited in some measure, have afterwards been restored to a perfect and lasting state of health, from the use of Matlock water.

" I have in the course of seven years, sent a great number of patients to Matlock, and in cases where medicine had not the least prospect of being serviceable ; all of whom have had perfect and lasting cures ; and I may with truth declare, I have not failed in one instance. However contrary to the opinion of some my practice may be, I have, after repeated trials, found, that in many cases much advantage has been gained by the administration of medicines in conjunction with the course of water-drinking; being well-timed, so as to act in an uniform manner, they had excellent effects, the water being greatly assisted In its operations.

" I perfectly agree with Dr. Percival, that a larger quantity of Matlock water may be drunk at a time, than of ally other mineral water I am acquainted with, owing to the entire absence of any mineral spirit; yet it is always adviseable to begin with small quantities. From the want of mineral spirit it is less apt to throw the circulation of the blood into irregularities, or quicken the pulse ; and therefore it must have the preference to Bristol Water in phthisis pulmonalis, hæmoptoe, diabetes, fluor albus, &c. In all these, I have experienced the most happy effects from it, as well as in hectic and low fevers, in hysteric and hypocondriac affections, in a profluvium or deficiency of the catamenia, in bilious disorders, in constitutions debilitated by long and severe vernal and autumnal intermittents, in disorders arising from long residence in hot climates, in broken constitutions brought on by hard and habitual drinking, and in weak and depraved appetites.

" The value of this communication would have been much increased, if Dr Armstrong had favoured the public with his general treatment of the patients, who have been fortunately under his care. He appears to lay considerable stress " upon the use of medicines in conjunction with the course of water drinking. Perhaps the hint which he has suggested, may be sufficient for the use of gentlemen of his own profession."

Various theories on the cause of heat in the Matlock water, have at different times come before the public; but none of them satisfactorily account for the phenomenon, which induces me to omit them all.
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