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The Museum of Natural History (South Kensington). Dr. Henry Woodward's Successor.

The Daily Graphic of January 1 publishes a portrait and the following outline of the career of Dr. A. S. Woodward, who succeeds Dr. Henry Woodward as head of the Geological Department of the Museum of Natural History:

"Dr. A. S. Woodward was born at Macclesfield in 1864, and was educated at the Macclesfield Grammar School and at the Owens College, Manchester. He entered the British Museum (Natural History) in 1882, at about the time of its removal to South Kensington. In 1892 he became Assistant Keeper in the Geological Department, and was engaged in researches on extinct vertebrate animals, especially fishes. He has written a catalogue of the fossil fishes in the museum in four volumes, of which the last volume has just been issued. Dr. Woodward is also author of the text-book entitled, 'Outlines of Vertebrate Palæozoic Fossils,' and published by the Cambridge University Press. He has travelled extensively on the continents of Europe and America, and while in South America worked in. connection with the Museum of La Plata, especially upon the newlydiscovered extinct ground sloth Mylodon and the horned tortoises. During last year he was engaged in researches in Greece at the spot about half-way between Athens and Marathon, where a deposit of red marl, containing extensive bone beds, yielded remarkable results. In 1896 he received the Lyell gold medal from the Geological Society of London, and Glasgow gave him the degree of LL.D. No more able or fitting successor to Dr. Henry Woodward (to whom he is not related) could be found than Dr. A. S. Woodward, and in his hands. the high reputation of British palæontological science will be well maintained."

Notes and Receipts.

We are indebted to Mr. Thos. Headridge for the following notes, which are likely to be of interest and assistance to many of our readers.

Ruble's Recipe.-Moisten zinc oxide in a Hessian crucible with nitric acid and calcine. The very solid zinc oxide thus obtained is ground very finely and made into a kneadable mass with zinc chloride solution (ZnCl) of 19 to 2 specific gravity; this mass hardens in a few minutes, and excels in great permanency.

Production of Dental Cements. - There are two kinds of dental cements, viz., zinc chloride cements and phosphate zinc cements. The former are the oldest. They are all powders of various descriptions, giving a stone-like mass upon admixture of various liquids. In the

case of zinc chloride cements, the powder consists of zinc oxide and glass, the liquid being zinc chloride; glass powder is equally well adapted for both.

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Powder very finely and mix; then tint with a small quantity of golden ochre or manganese. The compound, mixed before use with concentrated, syrupy zinc chloride solution, soon becomes as hard as marble, and constitutes a very durable tooth cement.

Rostaing's Formula.--First mix intimately 3 kilos. of zinc oxide with 5 to 50 grammes of boracic acid dissolved in water, and heat several hours to white heat, after drying. After cooling there will be found in the crucible an enamel of the hardness of stone, and of bluish or greenish colour. Same is rubbed up into a coarse sand and roasted in the air, which causes it to turn white. By heating with metallic salts any desired shade may be imparted to the enamel. The enamel powdered into a fine dust is prepared for use with a syrupy solution which is obtained by melting together in a crucible a mixture of calcium phosphate and zinc phosphate, dissolving the vitreous mass obtained thereby in diluted phosphoric acid, and boiling down the liquid to the consistency of syrup. An analogous recipe is the following:

Melt in a crucible an intimate mixture of I part of secondary calcium phosphate (CaHPO) with 15 parts of pure zinc oxide and 16 parts of secondary ammonium phosphate (NH),HPO4 until the mixture flows quietly and uniformly. The molten mass, when cooled, is powdered and dissolved in diluted phosphoric acid, and cadmium oxide, to the extent of 5 per cent. of the molten mass obtained, is added; when this is dissolved, evaporate to the consistency of syrup. Furthermore, knead a mixture of 2,500 parts of zinc oxide and 500 parts of magnesia with 50 grammes of boracic acid dissolved in water into a stiff paste, dry and calcine in a Hessian crucible for some hours at white heat. The greenish mass obtained is finely pulverised and roasted in the air until it turns white, and may be tinted as desired with manganese peroxide or ochre. The resultant powder is made into a paste with the solution above described, and furnishes a very firm cement.

According to another recipe zinc lime phosphoric acid solution is prepared as above indicated; then precipitate zinc silicate by mixing a diluted water-glass solution with zinc chloride, gather the precipitate on a filter, wash it well, dry and melt in the crucible. After

cooling, powder. Thirdly, calcine zinc oxide for several hours at white heat and intimately mix the finely pulverised oxide with 5 per cent. of melted zinc silicate. This mixture is mingled, for use, with 10 to 30 per cent. of the solution mentioned and gives a very hard dental cement, which solidifies with heating.-Pharmaceutische Zeitung.

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As binding liquid it is well to use exclusively acid-free zinc chloride, which one may prepare oneself by dissolving pure zinc, free from iron, in concentrated, pure hydrochloric acid, in such a manner that zinc is always in excess. When no more hydrogen is evolved, the zinc in excess is still left in the solution for some time. The latter is filtered and boiled down to the consistency of syrup.

Commercial zinc oxide cannot be employed without previous treatment, because it is too loose; the denser it is the better is it adapted for dental cements, and the harder the latter will be. For this reason it is well, in order to obtain a dense product, to stir the commercial pure zinc oxide into a stiff paste with water to which 2 per cent. of nitric acid has been added; the paste is dried and heated for some time at white heat in a Hessian crucible.

After cooling, the zinc oxide thus obtained is very finely powdered and kept in hermetically-closed vessels, so that it can absorb no carbonic acid. The dental cement prepared with such zinc oxide turns very hard and solidifies with the concentrated zinc chloride solution in a few minutes.

In place of the zinc chloride cements, phosphate zinc cements are, of late, more and more gaining ground. They all consist, essentially of zinc oxide and the thickest liquid of meta- or pyro-phosphoric acid; mix pyro- and meta-phosphoric, or dissolve in ortho-phosphoric acid either pyro-phosphoric acid, or meta-phosphoric acid, or pyro-phosphoric acid anhydride: the liquid may also contain zinc oxide, dissolved about to-From Scientific American Supplements.

The Open-air Treatment of Phthisis and the Condition of the Teeth. In a recent address to the Odonto-Chirurgical Society, Mr. H. B. Ezard drew attention to the very unsatisfactory condition of the teeth of many of the patients undergoing the open-air treatment for pul

monary tuberculosis. In this treatment, as is well known, the feeding of the patient is most important; and to obtain the greatest amount of value from the food it is necessary that the act of mastication should be efficiently carried out. Professional curiosity seems to have led Mr. Ezard to examine the teeth of the patients in a sanatorium in which he himself was undergoing treatment. The result of his investigation was as follows: "Out of 192 possible molars 12 were in action, and taking the average age, 26, out of the possible 32 teeth only 8 were in action, i.e., 75 per cent. of the first process of nutrition had been lost." These figures speak for themselves and indicate that the importance of the teeth has been in some cases unconsciously overlooked by medical practitioners in whose care such patients are placed. There is, however, another point in connection with the mouth to which Mr. Ezard did not draw attention, namely, the importance of rendering all mouths as far as possible aseptic by the removal of septic teeth, and the treatment of suppurative conditions of the gums and periodontal membrane. Recent writers have shown that the constant absorption of septic matter generated in the mouth is a fruitful cause of systemic disease, more especially of the alimentary tract. Such septic matter, if present in the mouth of those undergoing the open-air treatment, must to a great extent counteract the advantages gained by the remedies employed. In combating tubercle no stone should be left unturned in endeavouring to restore perfect nutrition, and the condition of the mouth certainly should claim the attention of those having the care of such patients.— Lancet.

The Royal Dental Hospital of London.

The Royal Dental Hospital, Leicester Square, has received 100 for the " General Maintenance" Fund and £100 for the "New Building" Fund from the Worshipful Company of Goldsmiths. The Hospital has also received £105 from an anonymous friend.

A Research Scholarship has been founded in memory of Mr. Storer Bennett for students of this School.

Mr. Howard Mummery has acceded to the request of the Committee of Management and the Medical Committee to become the first lecturer on bacteriology, and will commence his course of lectures in the summer session.

Royal College of Surgeons in Ireland-Dental Examinations. The following gentlemen having passed the necessary examination have been admitted Licentiates in Dental Surgery of the College:

Thomas Beaumont, Francis Xavier Costello, Ben Farrar Cowper, and Edward Thomas Patley.

Birmingham Dental Students' Society.

The tenth Annual Dinner of the Birmingham Dental Students' Society was held at the Grand Hotel, Birmingham, on Friday, November 29, the President, Mr. H. Percy Joscelyne, presiding; about thirty-five members and friends being present, including several of the leading specialists of the city. After the toast of "The King" had been duly honoured, that of the "Society" was proposed by Mr. W. F. Haslam, who, in a felicitous and humorous speech, gave the Society a good idea, viz., that mistakes as well as successes be brought before the Meeting, for as much, if not more, is learnt from them. He coupled with this toast the names of the Secretaries Mr. F. W. Broderick and Mr. R. H. Astbury. In acknowledging the toast Mr. Broderick spoke of the importance of the Society, which stands second to none in the University. "Birmingham University and Dental School was proposed by Mr. Albert Lucas, who attributed to dental students a degree of earnestness which was hard to beat. In reply, Mr. Humphreys dwelt on the birth of the University, and the fine Dental Museum, and acknowledged with pleasure some handsome donations from Messrs. Donagan and Bowater. Mr. J. D. Whittles, in reply, related some humorous incidents occurring in the last examination of the College of Surgeons.

The "President," proposed by Dr. McCardie, was drunk with enthusiasm, and suitably acknowledged by Mr. Joscelyne. The "Visitors," proposed by Mr. Malcolm Knott, was responded to by Dr. Smallwood Savage and Councillor Bowater in brief and humorous speeches.

The toasts were interspersed with songs, violin solos, and recitations by various members of the Society and friends, and a most pleasant evening was concluded by singing "Auld Lang Syne" and the National Anthem.

F. W. BRODERICK, Hon. Sec.

A Dental Bill for South Australia.

In the Legislative Council last week, the Hon. J. V. O'Loghlin introduced a Bill providing for the registration of dentists. The measure was read a first time, and the second reading will be moved next Wednesday. It provides that the Governor may appoint a board, consisting of five dentists qualified by diploma, who shall hold office for not more than three years. After the expiration of the

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