RICKETS (See Medicine-Index, Encyc.), is a disease so formidable to children, that we believe no parent will think the following abstract of Bonhomme's memoir on the nature and treatment of it too long even for this Supplement.

The change which the bones undergo in this disorder, has long been attributed to the action of an acid on their substance; but this supposition was grounded on mere conjecture and remote analogy. Bonhomme holds the same opinion on better grounds; and the principal notions which constitute the basis of his memoir are the following:

1. According to him, the nature of the rachitic disorder arises, on the one hand, from the development of an acid approaching in its properties to the vegetable acids, particularly the oxalic; and, on the other, from the defect of phosphoric acid, of which the combination with the animal calcareous earth forms the natural basis of the bones, and gives them their solidity. Whence it follows, that the indication resulting from this proposition, if once adopted, would be, that the treatment of rachitis must depend on two principal points, namely, to prevent the development of the oxalic acid, and to reestablish the combination of the phosphoric acid with the basis of the bones to which they owe their solidity.

2. The author proves, by experiments and observations, in the first place, that alkaline lotions of the parts affected with rachitis contribute to their cure; next, that the calcareous phosphate taken internally is really transmitted by the lymphatic passages, and contributes to ossification; and, lastly, that the internal use of calcareous phosphate, whether alone or combined with the phosphate of soda, powerfully contributes to restore the natural proportions in the substance of the bones, and accelerate the cure of rachitis.

With regard to the author's endeavours to prove that the calcareous acid is wanting in the bones of those who are disordered with rachitis, and that the development of oxalic acid contributes to the disease, we must not conceal that his memoir contains views rather than absolute proofs of these two positions. He declares, himself, he was not provided with the necessary means to establish an exact and complete analysis. He therefore presents his ideas, in this respect, merely as conjectures approaching to the truth.

The effect of the action of acids upon bones was before known; that is to say, that when deprived of calcareous phosphate, and reduced to the gelatinous parenchyma which forms one of their elements, they lose their consistence; and become flexible. Hence it was already conjectured by various physicians, that the rachitis was the effect of a peculiar acid.

A disposition to acæcence in the first passages is observable in all infants. The colour which characterizes this acæcence is often manifest in their breath, and even their perspiration. The bile corrects this disposition; but in general the bile is wanting in rachitic infants. It does not colour their excrements, and the acids accordingly are developed in a very decided manner. They disturb the circulation, and attack and soften the bones. As it is by defect of animalization that these acids develop themselves, it follows that their character is analogous to the fermentable vegetable acids, and more or less to the oxalic acid; and that, on the contrary, the animal acid or phosphoric acid ceases to be formed, and to unite with the animal calcareous earth; whence they are deprived of the principle of their solidity. This is the theory of Citizen Bonhomme.

In order to establish this doctrine upon precise experiments, it was requisite to analyze rachitic bones comparatively with those of healthy individuals of the same age; and as it is known that the urine of rachitic subjects deposits a great quantity of a substance of sparing solubility and earthy appearance, it would have been advantageous to have joined a complete analysis of this urine and its sediment. Citizen Bonhomme, not being provided with the means sufficient to make these analyses, and being besides of opinion that such rachitic bones as are destroyed by this malady exist in a progressive state of change, which might render their analysis scarcely susceptible of comparison, limited himself to a collection of some of the most remarkable phenomena of the urine, of the aged, the adult, and infants in the healthy state, of infants in the rachitic state, and of patients after the perfect cure of this disorder. From these observations he has deduced several important results.

It is known, that when the urine contains disengaged phosphoric acid, as happens to aged individuals, and in some peculiar circumstances of the system, if lime water be poured in, there is a speedy deposition of calcareous phosphate. It is also known, that when a solution of the nitrate of mercury is poured to the fresh urine of adults, a rose-coloured precipitate is formed, which is a phosphate of mercury produced by the decomposition of the phosphates contained in the urine. These two proofs are therefore extremely proper to ascertain the presence of phosphoric acid, whether free or combined, in a fluid which in its natural state contains a remarkable proportion. Besides this principle, the urine deposits more or less of sediment, either gelatinous or of an earthy appearance; and, finally, by evaporation, a saponaceous and saline extract, in greater or less abundance, is obtained by evaporation. By means of these four methods of examination, the author has ascertained the following facts:

1. In the healthy state, the sediment naturally deposited by urine is almost totally gelatinous in the infant and the adult; and in the aged individual it is charged with an abundant sediment of an earthy appearance similar to the earth of bones, which consequently is calcareous phosphate.

2. The quantity of brown saponaceous saline extract afforded by evaporation is greater in proportion to the age.

3. The presence of disengaged phosphoric acid, as shown by lime water, is none in the urine of infants, scarcely perceptible in that of adults, but very remarkable in that of old men. For two ounces of this last urine afforded by this means ten grains of phosphate of lime.

4. The decomposition of the phosphates by nitrate of mercury is not seen in the urine of infants; an abundant precipitate of a light rose-colour is produced in this way from the urine of adults; and in that of old men this precipitate is always of a grey colour, and very abundant. Hence Citizen Bonhomme concludes, that the phosphoric acid, whether at liberty or combined, does exist in the urine of healthy individuals in proportion to the diminution of the solids by age, and that it increases with the age.

With regard to the urine of rachitic subjects, the most remarkable facts are:

1. The abundant and apparently earthy sediment it deposits (spontaneously) is different from that of old men, by its colour, which is grey, and does not resemble phosphate of lime, and also by its much greater quantity. For a pound of this urine let fall two gros, whereas the same quantity of the urine of old men deposited only 45 grains.

2. The extract left by evaporation is likewise much more considerable than in other urine. It is one-third more in quantity than the extract afforded even by the urine of aged persons.

From these two first observations it follows, that the solids in rachitic subjects are destroyed with much more rapidity than even in old men; and that they afford a much more abundant portion of waste to the urine.

3. The light deposition occasioned by lime water in the urine of rachitic subjects is very small in quantity, brown, gelatinous when fresh, and pulverulent when dry. It does not at all resemble calcareous phosphate.

4. The deposition formed by the solution of mercurial nitrate is not abundant, neither of a rose-colour as in the urine of adults, nor grey like that of old men. It is always white, and consequently has no external resemblance to the phosphate of mercury. The author affirms that it resembles a mercurial oxalate. Lastly, the urine of the same rachitic subjects when cured, exhibits again all the characters observed in the urine of healthy children. We shall not add to the reflections of the author. In effect, though these first observations are curious, they are incomplete. We offer them to physicians simply as the elements of an investigation which it is of importance to continue and bring to perfection. We shall therefore proceed to the curative and experimental parts of the memoir.

One of the facts which it was of the utmost importance to establish, was the transition of the calcareous phosphate from the intestinal passages, into those of circulation and secretion. Fourcroy had already well ascertained that the serum of milk contains this fact naturally. Vauquelin had proved its existence, as well as that of pure soda, in the seminal fluid; but was it possible that it could pass unaltered from the stomach and intestines into the vessels which contain the blood and lymph? Could it by this means apply itself to the bones? This was to be ascertained by experiments; and the following are the experiments made by Bonhomme for that purpose. We give them in a translation of his own words.

"I caused (says he) several young fowls of the same incubation to be fed in different manners. Some received the usual food without any mixture; others received daily a certain quantity of calcareous phosphate mixed in the same paste as formed the support of the others; and, finally, one of them was fed with variations in the use of the mixture; the calcareous phosphate was sometimes given and sometimes suspended. When these fowls, after two months, had acquired their ordinary growth, I examined and carefully compared the state of their bones. The progress of the ossification in the epiphyses was various according to the nature of the food the animal had received. The bones of the last fowl, which had received the phosphate only from time to time, were rather more advanced than the bones of those which had been fed without mixture. The bones of those fowls which had been habitually fed with the mixture were evidently more solid, and their epiphyses were much less perceptible. Simple inspection was sufficient to show these differences when the bones were mixed together.

"I had fed several young fowls of the same incubation according to another plan. Some were fed on a simple paste, without mixture; for others it was mixed with pulverized madder-root; and a third composition was made of this last paste and calcareous phosphate. This was also given habitually to other fowls. When after two months I examined the progress of ossification in the bones of these different animals, I easily perceived the red traces of the madder in the ossified parts of all those which had used it; but I observed that the ossification was not more advanced by the simple mixture of this root than by the ordinary food; on the contrary, the bones of those fowls which had followed the phosphate mixed with madder were much more solid than the others. The red colour served admirably to distinguish the extremities of the long bones from their epiphyses. After an exact comparison, there could be no doubt of the efficacy of calcareous phosphate in favour of the progress of ossification. The virtue of the madder seemed confined to that of giving colour to the ossified parts."

From these experiments, it was natural to make the trial of calcareous phosphate in addition to the remedies made use of in the treatment of rachitic subjects. Here follows what the author himself says of two remarkable instances in which the calcareous phosphate was administered with success:

"The daughter of Mr. Ranchon watch-maker, aged two years and a half, walked with a feeble and tottering pace, and the extremities of all her bones presented epiphyses very..." very prominent. In this situation she exhibited the appearance of imperfect rachitis, or the first period of this disorder. Alkaline lotions, which I immediately advised, were attended with a good effect. Her sleep became more firm; and as the first passages were in a good state, I gave, without internal preparation, one scruple of a mixture of equal parts of phosphate of lime and phosphate of soda twice a day. In the course of three weeks her legs were perfectly restored; and this amiable infant has ever since had the satisfaction to run with spirit and agility.

"A female infant, of the name of Boiard, aged four years, had experienced from her birth the most decided symptoms of rachitis. The protuberance of the epiphyses and tumefaction of the abdomen still indicated the disease. The impossibility of supporting herself and walking at the usual age confirmed these unfortunate symptoms. By degrees the glands of the neck and of the micturition became swollen; the teeth were blackened, became carious, and were not replaced. This situation became still more afflicting by crises almost periodical at an interval of three or four weeks. At these afflicting periods, a fever of considerable strength, cardalgia, and even convulsions, particularly in the night, were observed. The termination of each paroxysm was announced or ascertained by abundant stools, and the evacuation of urine strongly charged with an earthy sediment. The imprudent exhibition of a purge at the beginning of one of these crises had nearly deprived the patient of her life. In this state it was that I beheld her for the first time in the month of January 1791. The alkaline lotion was the only remedy the mother adopted in the first instance, and it produced a remarkable effect. After eight days the infant was so much better as to be able to support herself. The remedy was then laid aside, and eight days afterwards the child was incapable of standing without support. The use of the alkaline solution being renewed, was attended with the same success, and its discontinuance was again followed by the complete return of all the symptoms. In the first days of March, the other remedies I had advised were exhibited. The constipation which had always existed became less, and the following crises was effected without pain. And at length the convulsions, the pains, and the crises disappeared; but the impossibility of walking still remained. At this time, namely on the second of May, I gave the child the phosphate of soda and calcareous phosphate mixed together, in the dose of half a dram twice a day. At the end of the month she was able to stand upright, leaning against a chair, and the swellings began to diminish. She continued for a long time afterwards to take the mixture of the phosphates. I likewise gave her occasionally one grain of the extract of bile, prepared with spirit of wine; and at length in the month of July I had the pleasure to see the patient run and play in the middle of the street with the other children of her own age, &c."

The author gives other instances of this medicine being administered with complete success to rachitic children, and one in which it was attended with the best effects in a case of incurvated spine. These it is needless to insert, because we trust that none of our learned readers will have recourse to the medicine without the advice of a physician; and to him an enumeration of cases could serve no purpose. It may be proper, however, as alkaline lotions and their beneficial effects are mentioned, to give here the author's account of the lotion which he used.

"In ordinary cases of rachitis, particularly at the commencement of the disorder, it is of advantage to use a simple solution of potash to wash the parts affected. This solution is made by dissolving from half an ounce to an ounce of purified potash in a pound of distilled or very pure spring water. When it is to be used, the skin must first be rubbed with a dry cloth, or a piece of fine flannel. After this precaution, the diseased extremities are to be washed carefully with the warm solution, and at length wiped, so as to leave no trace of moisture. This practice and washing must be repeated at least twice a day. I can affirm, from repeated trials, that it will soon be attended with success."

In a note on this passage, M. Hallé, who analysed the memoir at the desire of the Society of Medicine at Paris, judiciously observes, that as pure potash, or the vegetable alkali, is a most powerful caustic, it cannot be used in these proportions; adding, that he found one-eighth part of the salt here indicated to form too strong a lotion for the skin of an infant. M. Bonhomme, upon enquiry being made, informed him, that the potash which he used was that of the shops, which is very far from being pure; and Mr. Nicholson conjectures that it was the common salt of tartar of our shops. This, we think, extremely probable, especially as M. Bonhomme assures us that even a lixivium of wood-ashes, such as is used for washing fine linen, may answer the purpose extremely well.

For a fuller account of this interesting memoir our readers are referred to the 17th volume of the Annales de Chymie, or to the first volume of Nicholson's Philosophical Journal.