number who refer all the worst forms of it to the drugs employed, that some of the members of the late Admiralty Commission, we learn, had the opportunity of seeing a soldier patient in whom the constitutional effects of syphilis were so formidable that he died of that disease within six months of contracting the primary lesion; and in that case, at any rate, no mercury whatever had been exhibited. We gather some important facts from Dr. Paynter's report on the French troops serving in Algeria, bearing on this subject of the effects observed in the natural evolution of the disease. The paper is to be found in the sanitary section of the new Army Medical Blue-book. Dr. Paynter says that among the native Arab populatiou syphilis is the only really prevalent disease, both in the towns and in the country districts. As a general rule these people never seek any advice or treatment. and one meets with most dreadful objects suffering from the malady in its various forms. Extensive disease of the bones, where no kind of treatment had been at any time adopted, is frequently met with amidst these people. The appearance of some of the sufferers, even to those accustomed to witness disease, is described as most revolting. One French army surgeon had seen a native woman, the bones of whose face had been completely ulcerated away by the disease now under consideration. She had never received any treatment whatever, either for the primary or other stages of the affection. Where these native people first contracted this disease, or how it was introduced among them, it is difficult to form any idea; but it is quite evident that it exists to a most lamentable extent, and may, with other causes too numerous and varied to define, eventually and at no distant period, exterminate the subdued tribes from the face of this most beautiful country.-London Medical Times and Gazette, November 30, 1867.

RESECTIONS IN LONDON HOSPITALS.-Prof. Edmund Andrews, in a letter to the Chicago Medical Examiner, writes as follows:

"Resections of the knee are extensively practiced, even in children. The surgeons deny that it will prevent the limb from growing, provided you do not remove the whole of the epiphysis. The practice here is very often to amputate or resect inflamed knees,

in cases where a Chicago surgeon would save the limb and effect a cure. They operate in the first stages, while the disease is yet a simple inflammation, without suppuration or caries; and while, according to American experience, the knee is perfectly curable. In justification of this practice, they say that the cure, if accomplished at all, would be excessively slow, and, therefore, the hospitals could not keep the patients long enough. They would go out and run about on their limbs, and exasperate the disease to actual caries; therefore they think it better to operate at once. The real fact is this: They treat their patients only by medicine, local applications, and rest in the foul air of the wards, and find that they die. As a general rule, they are grossly ignorant of the fact that adhesive-strap extension and pure air will cure the patient without operation. So they take the easiest course, and cut out the joint, or cut off the limb, and thus end the matter, and frequently kill the patient."

Ozone.

It is now confidently asserted that, through the persevering labors of several distinguished chemists, the true nature of this important agent has been discovered. In the Medical Times and Gazette, Oct. 5, 1867, will be found a very interesting paper on this subject with a resumé of the various hypotheses on the nature of ozene, which have been propounded from the time of its first observer, Van Marum, in 1785, or of its real discoverer, Professor Schönbein, in 1840, down to the satisfactory solution of the present day.

Andrews and Tait, in a paper presented to the Royal Society in 1860, confirmed the previously known fact that only a small proportion, in extreme cases only one-twelfth, of the oxygen can by the electric discharge be converted into ozone, found that a constant and considerable diminution of volume accompanied the change. 100 volumes of oxygen, when subjected to the silent discharge, may contract to about 92 volumes. Hence ozone must be denser than oxygen. But another important fact was observed. Mercury, or some other oxidizable substance, was introduced into

the ozonized oxygen, and the ozone was entirely absorbed. Strange to say, the oxygen which remained behind was found to have precisely the same volume as it had before the removal of the ozone. If 92 volumes of ozonized oxygen were so treated, 92 volumes of oxygen free from ozone would in all cases remain behind, so that the density of ozone appeared to be absolutely infinite. On the other hand, if the ozonized oxygen were heated, the original 100 volumes would be obtained, because, as every one knows, ozone is destroyed by heat.

Andrews and Tait did not attempt to account for this extraordinary fact; but soon afterwards Dr. Odling suggested an explanation which has recently been confirmed in a most striking manner by an experiment of Soret's. (Comptes Rendus, Nov. 27, 1865.) It is conceded by nearly all chemists that each molecule of oxygen in the free state consists of two atoms-that, in fact, the true formula for free oxygen is O. Odling suggested that the formation of ozone might really be the condensation of another atom of oxygen into each molecule, and that the formula for ozone might therefore be O,, and its density one-half greater than that of oxygen. When 100 volumes of oxygen were reduced by ozonization to 92 it might be supposed that 8 volumes of oxygen combined with 16 volumes, and produced 16 volumes of ozone. The change might be represented in this way:

40, 80, 803.

a molecule of ozone O, occupying the same volume as a molecule of oxygen O. The absorption of the ozone by mercury, iodine, etc., might really be only the removal of the third atom of oxygen, which would of course leave the volume unaltered.

The same view would account for the mutual reduction which ozone and peroxide of hydrogen exercises upon one another, and, in fact, for all known re-actions of ozone.

This beautiful hypothesis, however, must have remained a mere hypothesis but for the remarkable experimental verification which it has received from the hands of M. Soret. We have seen that

all ordinary substances are only capable of removing one atom of oxygen from each molecule of ozone; but Soret has at length succeeded in finding a body-oil of turpentine-which absorbs the whole molecule, the whole three atoms of oxygen. To take our previous illustration, if the 92 volumes of ozonized oxygen were treated with oil of turpentine, a dense white cloud would appear, the ozone would disappear, but instead of the volume remaining the same it would contract to 76 volumes, the 160, having been removed bodily instead of being merely reduced to 160.

This experiment seems to place the matter beyond a doubt, and instead of the mass of hypotheses which so lately reigned, we have now a simple, beautiful, and coherent theory which affords an intelligible explanation of known facts. It is the more to be rejoiced at, since the importance of ozone in art as well as nature seems to be rapidly developing, and it is impossible to say how high that importance may rise.-Medical News and Library.

Gentian Root as a Dilator.

Professor Winckel in Rostock, recommends (Deutsche Klinik, 1867) the radix gentianæ rubræ as a new, simple, and cheap means of dilatation for surgical and gynecological purposes. His attention was first directed thereto by an article of John Jacob Haeberl, published in 1834, in which the author states that having operated for atresia uteri and desiring to keep open the orifice made by the trocar, he introduced a good, firm plug of radix gentianæ, and that on the following day he found no small difficulty in withdrawing the same, which had increased to twice its former size. According to Dr. Winckel's observations the gentian root has the follow ing advantages over laminaria: 1st. Its cheapness, the ease with which it can be obtained, and the fact that the physician can so easily cut plugs and bougies of any size to suit his requirements. 2d. Its somewhat smaller power of absorption, as compared with laminaria, is compensated by our being able to obtain larger pieces of it (one and one-half to two inches in diameter) so that it can be used for the dilatation of openings already too large for laminaria. 3d. The fact of its remaining free from smell constitutes an immense advantage, for even laminaria, though in a much less degree than sponge-tents, often becomes quite fœtid.

The radix gentianæ may therefore be used with special advantage in strictures of the vulva, vagina, and uterus; for tamponing the uterus in smaller hæmorrhages, for the induction of abortion, for dilatation after operations for atresia of the genital organs. Whether it is also applicable to stricture of the urethra, to affections of the lachrymal ducts, etc., remains to be seen.-All. Med. C. Zeitung, 1867.

Two Cases of Locomotor Ataxy Treated with Nitrate of Silver.

BY C. A. HINGSTON, M. D., LONDON.

A sparely nourished, very intelligent, old-looking man, aged forty-four, residing in Plymouth, became a dispensary patient in January, 1866. He was quite blind and confined to his bed, and gave the following account of himself:-About four years ago, he first noticed a weakness of his sight, which gradually increased, until it disappeared first in the right eye and then in the left. His eyes were at the time examined with the aid of the ophthalmoscope, and he was told that the optic nerves were excavated, but without any other morbid condition. About eighteen months ago he began to suffer from shooting pains through his limbs and body, followed by slowly increasing weakness of the lower extremities, until recently he has been compelled wholly to keep to his bed.

The following were the symptoms observed:-His skin, pulse, tongue, bowels, and urine were apparently natural. He complained of constant pains of a shooting or darting character through the limbs and body; these pains were of equal severity during the day and night, and such as almost entirely to prevent sleep. There was almost complete loss of sensation of touch in the feet and legs, though temperature was well preserved. The muscular power of both limbs were very considerable, and he was able powerfully to resist flexion and extension, so much so as to render the production of those movements impossible without his consent.

On attempting to make him walk, the loss of co-ordination of movement was very marked; his legs flew about in all directions, and unless supported, he fell. He stated that the ground felt as if composed of round balls.