The oil of cassia is not only secured from the bud of the cinnamon cassia (Nat. Ord. Laurineœ), or so-called "Chinese cinnamon," but also from its bark, stems and leaves.

The following table, giving the results of distillations from authentic crude material, gives a correct idea of the character of the oils yielded by the different parts of the cassia plant:

Consequently, as the criterion of value of the oil is its cinnamicaldehyd content, the oil produced from the bark and buds of the cinnamomum-cassia is not as valuable as that produced from its stems and leaves.

The finest and best oil of cinnamon to the contrary, however, is obtained from the bark of the cinnamomum-zeylanicum (Nat. Ord. Laurinece), a plant peculiar to the Island of Ceylon; while a much inferior oil is also obtained from the stems and leaves of the tree.

(The oil distilled from the leaves of the cinamomum-zey. lanicum contains a very large percentage of eugenol, and only about 0.1 per cent of cinnamic-aldehyd. On the other hand the oil obtained from the bark contains usually from 40 to 80 per cent of cinnamic-aldehyd, and only from 4 to 8 per cent of eugenol.)

There is a great difference in the many varieties and physical properties of the oil of cinnamon. That distilled from the coarse bark, gathered from the large branches of the wild forest tree, being radically different from the oil secured from the bark of small bushes and the shoots of four to ten-year-old trees, both wild and cultivated. The finest grade of the oil of cinnamon is produced from the inner bark obtained from the shoots of cultivated trees. It possesses a rare aroma and piquancy, which is more or less lacking in the various oils distilled from the many grades of bark taken from the wild trees.

The genuine oil produced from the choice bark of the cinnamomum-zeylanicum can seldom if ever be found upon the open market. In fact, it is a very hard thing to find any grade of the true oil of Ceylon cinnamon in our drug stores. If, by chance,

it is found at all, in ninety-nine cases out of a hundred it is that distilled from the coarse bark of the wild forest trees, and prob ably in nine cases out of ten even this inferior oil will be found adulterated with from 30 to 60 per cent of the still less valuable oil of the cinnamon leaf.

Consequently, dentists rarely, if ever, know anything about the virtues of the true oil produced from any of the better grades of the bark of the cinnamomum-zeylanicum.

The finer grades distilled from selected bark of Ceylon cinnamon cannot be produced under $1.25 to $2.50 per ounce. Even the poorer grade, adulterated as it is, is easily worth in small quantities from 60 to 80 cents per ounce.

The Essential Oils are composed of two or more separate and distinct constituents:

1st. A highly aromatic, and more or less soluble part, which is the inherent life or active principle of the oil. 2nd. A compound of resins, terpenes or other hydro-carbons, which are less soluble and have no value to the dentist.

Unfortunately the Essential Oils of commerce usually contain but a comparatively small percentage of the aromatic radical, or life principle of the oils, and generally a very large percentage of terpenes, resins, and other inert matter.

While the criterion of value of the oils of cinnamon and cassia in their cinnamic-aldehyd contents, the therapeutic and mechan ical efficacy of the oil of eucalyptus is due to the percentage of its characteristic constituent-eucalyptol (cineol)-while the oil of cloves is valued according to the percentage of its aromatic component or active principle-eugenol.

All that I have said concerning the numerous varieties and varying physical properties of the oils of cinnamon and cassia is still more or less true of the other Essential Oils. For instance, there are many species of the eucalyptus plant (Nat. Ord. Myrtaceae), and an endless variety of species of other orders of plants which yield so-called "oil of eucalyptus." Unfortunately, however, most of them give a very large percentage of phellandren, or other inactive and undesirable substances, and but very little of cineol (eucalyptol).

When their physical properties are taken into consideration, many of the" oils of eucalyptus" found upon the market—from a dental point of view-possess little or no value, being sadly deficient in cineol content, and composed mainly of hydro

carbons of a disagreeable turpentine oil odor, which are irritating to the organs of respiration, and, more or less, to the soft tissues.

In many cases these undesirable hydro-carbons and inert matter compose from 65 to 85 per cent of the oils found upon the market. Consequently when the dentist purchases the ordinary oil of commerce, he usually gets something "cheap and nasty," and then wonders why he does not secure better results when he comes to treat and disinfect the root canals of the teeth after the removal of the pulp, or cases of apical pericementis.

I have been pleased to exhibit to the dental profession the Essential Oils produced for the purpose of incorporating into Dentacura, and at the request of eminent dentists, the Dentacura Company are now offering such oils to the profession. These oils are peculiar in the fact that they represent, in the purest and most concentrated form, the aromatic radical or active of each of the oils. They are secured by the separation of the oils into their component parts (one of the latest achievements of modern chemistry), and the absolute elimination of all terpenes, resins, and other inert matter; or, in other words, they contain nothing but the inherent life or active constituent of each oil.

I thank you for the opportunity of contributing to this interesting domain of the dental art, and trust I have added at least something to the better understanding of the physical and chemical properties of the Essential Ois.-Indiana Dental Journal.

DENTISTRY IN OUR PUBLIC SCHOOLS.

Boston has again taken a step forward in the establishment of baths in one of her public schools. All children have to be taught to read and write; that is, they do not acquire it by instinct; all children have to be taught to clean their teeth, if they are cleaned. I regret to say that most children have to be made to. The constant admonition of the parent is not sufficient, if we may judge from cases that come under our observation daily. Is there any logical reason why a child should be allowed to go to school with a filthy mouth to pollute the atmosphere of the school-room with foul odors of ulceration and decay? A dirty face is a virtue in comparison, and yet that is

not tolerated. I would make it a rule that all children should brush their teeth before making their appearance in school. Let the teachers in the various departments examine each mouth; a glance would be sufficient. When unclean, have facilities at hand for cleaning or send the child home to do it. The diɛgrace would arouse their pride where the admonitions of the parents fail. Let us have free books, and, I would add, free tooth-brushes, if need be, in our schools. -Information.

MOUNTAIN TOOTHACHE.

The Physician and Surgeon says: "We are still far from correctly understanding the influence on the human organism of changes in climatic conditions and variations of atmospheric pressure, and there is a wide field of useful research in this direction. La Médecine Moderne tells us that a curious malady, which is apparently due to influences of this kind, has been lately observed by M. Hafner, of Zurich, among the engineers and workmen engaged in the construction of, the railway on the Jungfrau. At the end of the first eight or ten days after commencing work, each newcomer is seized with extremely violent pains in several teeth on one side of the jaw, accompanied by swelling of the gums and inflammation of the tissues of the cheek. The affected teeth are exceedingly sensitive to pressure, and mastication becomes very difficult. The pains increase up to the third day, after which they diminish gradually, and cease at the end of six or seven days. After their disappearance there remains no trace of the previous affection or troublesome sequelae of any kind, and no alteration can be detected in the teeth. M. Hafner considers that the trouble is a phenomenon of acclimatization. He points out that the men working on the railway are obliged to remain constantly in an altitude of nearly 300 metres, and in each case the same interval elapses between arrival and the manifestation of symptoms. When once the attack is over there appears to be no tendency to recurrence."” -Information.

ICED CHLOROFORM has been used as an anaesthetic at Wurzburg, Bavaria, in over 14,000 cases without a single unpleasant result. The advantages claimed for this preparation of chloroform are the quickness of its action, its comparative freedom from darger, and the absence of nausea and depression so common with other anæs hetics.-The Plexus.

Department of Pharmacy.

WM. J. JACKSON, PH.G., M. D., Editor in Chief.

Professor of Pharmacy, College of Physicians and Surgeons, of San Francisco.

J. HENRY FLINT, Ph.G.

A. C. BOTHE, A. M., M. D.

A. F. WERNER, A. B., M. D.

T. W. CONNELLY, Ph.G.

COLLABORATORS.

J. J. KEEFF, Ph.G., M. D.
HAROLD COTTELL, Ph.G.

P. A. DUBOIS, Ph.G.

J. F. DILLON, A. M., M. D.

The Editor of this Department is not responsible for the views of contributors. All communications relating to the Editorial Department of Pharmacy should be addressed to DR. W. J. JACKSON, 44 Third Street, San Francisco, Calif.

PRACTICAL PHARMACY OF INTEREST TO PHYSICIANS.

The paper by Prof. Henry P. Hynson on "Practical Pharmacy and Dispensing," read at the meeting of the American Pharmaceutical Association, held at Richmond, Va., in May, is pregnant with suggestions to the physician. Prof. Hynɛon, with the view of getting up-to-date data, sent out, prior to the meeting, the following circular to the leading druggists of the country:

"In the interest of Practical Pharmacy and Dispensing,' kindly select out of the last twenty-five prescriptions you have filled the one that required the most pharmaceutical skill, the one that gave you the most trouble and annoyance, or the one that was the most difficult to prepare. Copy it on the return card, attached, and mail. If possible, add note, stating any peculiarity of manipulation followed."

To this the professor received 95 replies, from which the following deductions have been drawn:

"Of the 78 prescriptions received through the kind courtesy of 69 members, 52 were for mixtures; 8 for hard capsules; 5 for suppositories; 5 for pille; 3 each for ointments and powders; 1 each for a dusting powder, konseals, and soft capsules.

"It plainly appears then that mixtures present more than half of the difficulties that come to the average dispensing pharmacist. This is largely due, no doubt, to the existing incompatibilities, but quite as often, perhaps, to the fact that bad prescribing and indifferent compounding could be so easily obscured here, as elsewhere.

"A careful examination of the prescriptions for mixtures re