The Diabetes Mellitus, though sometimes terminating in recovery, is yet well known to be a disease which has in general refilled every remedy hitherto recommended for its removal. Every attempt, therefore, to improve the practice in that affection, may justly be considered as deserving particular attention. The ingenious author of the work now before us, recommends a mode of treatment, which, in some instances, has been decidedly productive of remarkable benefit. It may justly, therefore, be considered as well meriting a fair trial in future cafes. 

The first cafe here related, is that of Captain Meredith, of the Royal Artillery. When he came under Dr Rollo's care, on the 16th of October 1796, he voided about twelve quarts of urine in twenty-four hours. This urine, seven quart-bottles of which he had preserved, having been voided during the course of the night, was of a light straw colour, had no urinous smell, but emitted somewhat of a violent flavour, and was very sweet to the taste. He was affected with 1 excessive thirst, and had drank, during the day, feven or eight quarts. His tongue was somewhat whitish, but moist: there was a cleanness in his mouth, and he spat a white frothy saliva, of a sweetish taste. His appetite for food was variable, sometimes unusually keen, particularly at uncommon times, as during the night. His face was fulfilled, his skin dry, but not unusually warm, and his pulse did not exceed eighty-four strokes in the minute. He was frequently sick, and threw up a viscid matter, of a bitterish taste, but with some sweetness. After eating, he complained of a pain of his stomach, which in general continued about half an hour. He complained of a constant pain in the region of the kidneys, extending forwards, but more particularly in the right, in which there seemed to be a greater fullness and tenderness to the touch. There was likewife a retraction of the testicle, with a weakness, sense of coldness, and at night an (Edematous swelling of the leg on the same side. He also complained of a pain and tenderness of the great toe. He felt also a lingular fluttering fenfation in his belly, extending from the fituation of the kidneys. He was regular in his bowels, though sometimes inclined to costiveness. His stools were of a greenish colour, and had no unpleasant smell. The prepuce of the penis did not retract. It had a whitish appearance, with excoriation and soreness, but was not swelled. His gums were reddish, and had the appearance as if affected by mercury. The teeth felt to him loose. There was a fullness about the eyes, with a turbid yellowish cast, and, he had slight occasional headaches. He had not been particularly restricted in diet, which consisted of animal food and vegetables; and he drank from a pint to a bottle of port wine daily. His other drink was toast-water. He used exercise, both in the way of riding and walking; but he could not walk above two miles without much fatigue. At this time thirty-six ounces, Troy weight, of his urine, analyzed by Mr Cruickshank, yielded by evaporation three ounces and one dram of saccharine extract, of the appearance of molasses, but thicker. According to this proportion, his whole urine for a day, would have yielded twentynine ounces Troy weight; an astonishing quantity to be separated daily from the system. Treating some of this extract with the nitrous acid, Mr Cruickshank procured the saccharine or oxalic acid. With a smaller proportion of the acid, it produced a substance which, in appearance, taste, and smell, could not be distinguished from honey. Two portions of blood, about four ounces each, were taken from his arm. These in appearance exactly resembles what is described by Dr Dobson, excepting that the serum did not impart a sensibly sweet taste. The crassamentum of the first cup had a slight buffy coat ; the craffamentum of the fecond had more. The buffy coat in both was of a bluish colour, similar to "what mercury sometimes produces. A portion of blood from a healthy person, drawn on the same day, was placed in the same room, and in the same circumstances with one of the portions of diabetic blood. In two days the diabetic blood assumed a caseous appearance on the surface, and the whole mass became dry and resinous, without having undergone any apparent putrefactive process. At the end of sixteen days, it remained in the same state; whereas the healthy blood exhibited evident marks of great putrefaction in four days ; and it became necessary to throw it away on the seventh.

When this patient came under Dr Rollo's care, his disease had been of seven months standing. During that time he had taken some remedies, under the direction of an eminent physician at Yarmouth, the principal of which were Peruvian bark and alum. He had fallen away very considerably in flesh and fat; for, in October 1794, when in apparent health, he weighed sixteen stones and eight pounds; and in November 1796, he weighed only eleven stones and eight pounds, showing a loss by the disease of no less than five stones in weight. For six months preceding the attack of the diabetes, he was often sick, and vomited at least two or three times a-week ; and he frequently brought up from the stomach, during these vomitings, different things which he had eaten several days before. These seemed to be unaltered, and the taste was very generally four. He always ate heartily, and drank freely, but not intemperately. He was fond of high-seafoned and fat dishes. He had been subjected to two regular attacks of gout, and had at other times two severe fits of cholic. He had been twice married, and had two children. He was, in the thirty-fourth year of his age, five feet eleven inches high, of a fair complexion, with light-brown hair, and dark-blue eyes. From an attentive consideration of all the circumstances of this case, what appeared to Dr Rollo to be the principal objects of treatment, were, to destroy the saccharine process going on in the stomach, to promote a healthy assimilation, to prevent the supposed increase of absorption from the surface, to diminish the increased action, and to change the imagined derangement of the kidneys. With these intentions the following plan of treatment was resolved upon.

1. His diet to confift principally of animal food; for breakfast, a pint and a half of milk mixed with half a pint of lime water, bread and butter; at noon, plain pudding, made of blood and fuet only; at dinner, game, and old meats which have been long kept, and, as far as the stomach may bear, fat and rancid old meats, as pork, taking care always to eat in moderation; for supper, the same as breakfast.

2. For drink, he was allowed daily four quarts of water which had been boiled, and in which was dissolved a dram of the kali sulphuratum. He was strictly forbid to use any other article, excepting these, either in the way of meat or drink.

3. His skin to be anointed with hogs lard every morning. Flannel to be worn next the skin, and the gentle exercise only to permitted, but confinement to be preferred.

4. A draught to be taken at bed-time, confifting of twenty-five drops of tartarised antimonial wine, and twenty-five of tincture of opium and the quantities to be gradually increased.

5. An ulceration, about the size of half a crown, was directed to be produced, and maintained externally, immediately opposite to each kidney. And, lastly, his bowels were to be kept regularly open, by a pill of equal parts of aloes and soap.

This treatment was begun on the 19th of October, and, so soon as the 21ft, some changes occurred. He made, in twenty four hours, only six quarts of urine, and drank only three quarts of the sulphurated alkaline water. The urine was not so pale, had a cloud in it, and was more urinous in smell. 

On the 1ft of November the urine did not exceed four quarts, while it was of a higher colour, and more urinous smell. His skin was moist and he perspired freely; his stools were large, and very offensive, and he was in every respect much easier, though he complained of much pain from the ulcerated parts of the loins. Imagining that the quantity of alkaline salt, which he took daily in the kali sulphuratum, might have some improper effect on the kidneys, it was resolved to try hepatifed ammonia, on the suggestion of Mr Cruickshank, who was of opinion, that it might prove a more certain and active medicine in diminishing the action of the stomach, as well as the action of the system m general. He was therefore directed to take five drops of it, in each half-pint tumbler full of water, which he used as drink. The ill day he took thirty-five drops at different times, which in the evening, produced sickness and vomiting, with giddiness and drowsiness. He was therefore diredled to leave off the hepatifed ammonia for one day, and then to begin with two drops to each tumbler full of water. On the fourth, he drank only two pints of water, and made only two quarts of urine, which was not sweet, and deposited a red sandy, or lateritious sediment. 

On the 5th of November, the opiate at bedtime was discontinued ; and on the 8th the rubbing with the hogs lard was left off. Between the 4th and 14th of November, in consequence of some irregularities on the part of the patient, particularly drinking beer and tea, the disease was to a flight degree reproduced. 

On the 14th, therefore, an entire abstinence from vegetable matter was directed; nothing was allowed approaching nearer to it than milk; and even this was directed to be left off, and strong beef-tea substituted, should the disease not disappear. This soon produced a favourable change, his urine became again of a much Higher colour, and its smell and taste quite urinous. He afterwards continued for some time with tolerable regularity on the course already mentioned, and by the 18th of December his disease seemed to be in a great measure overcome; he was therefore desired to eat half a pound of bread as a daily allowance, and to take exercise more freely. 

On the 30th of December, Dr Rollo found that since the 18th he had continued free from the disease. He was now in high spirits, and rapidly gaining flesh. His urine did not exceed two pints in the twenty-four hours. It was often under that quantity, and perfectly urinous. He now weighed thirteen stones and one pound; so that he had gained about alone and a half lince the end of November; which furnished a convincing proof, not only of the removal of the disease, but also of the disposition to it. 

After this period, Captain Meredith might be considered as continuing free from complaints. He took exercise freely, both in the way of walking and riding. He ate a sufficient proportion of bread, potatoes, and other vegetables, without any inconvenience- His appetite was good and natural, and his bowels regularly open. His urine continued perfectly natural, and, in general," did not exceed a quart in twenty-four hours. Of this urine, which was of the ordinary taste and smell, nine ounces were evaporated, -and yielded of a brown and pungently saline bitterish-tasted matter, without tenacity, three drams and twenty grains, a product excessively different from the saccharine extract resembling molasses, which his urine yielded in October. The product now obtained was very nearly the fame, both in quantity and quality, as Dr Rollo obtained from his own urine, which, he had every reason to believe, was in the healthy state. About the middle of March, Captain Meredith continuing in a state of health, was ordered on active service; to which he very readily assented, being satisfied that his health now enabled him to execute the duties of his station.