An American has discovered a beautiful alloy, which has been most successfully applied as a substitute for gold. It is composed of pure copper, 100 parts; pure tin, 17 parts; magnesia, 6 parts; tartar of commerce, 9 parts; sal-ammoniac, 3.6 parts, and quicklime, 1.6 parts. The copper is first melted, then the lime, magnesia, sal-ammoniac, and tartar are added, little at a time, and the whole is briskly stirred for about half an hour, so as to mix thoroughly, after which the tin is thrown on the surface in small grains, stirring until entirely fused. The crucible is now covered and the fusion kept up for about thirty-five minutes, when the dross is skimmed off, and the alloy found ready for use. It is quite maleable and ductile, and may be drawn, stamped, chased, beaten into powder, or into leaves, like gold leaf, in all of which conditions it is not distinguishable from gold even by good judges, except by its inferior weight.
Imitation Silver.
Combine by fusion 1 part pure copper, 24 parts block tin, 1 1/2 parts pure antimony, 1/4 part pure bismuth, and 2 parts clear glass. The glass may be omitted save in cases where it is an object to have the metal sonorous.
Care of Teeth, Mouth, and Breath.
The teeth, through negligence and ignorance, receive less attention among the majority of people than any other subject of a personal character. The care of children’s teeth is very important, and if parents do not post themselves in the matter frequent visits to a skilled dentist should in their case be imperatively enforced, as well as upon the older members of the family.
The first teeth of the infant are called the deciduous or milk teeth, and are twenty in number—ten in each jaw. These twenty teeth are as follows: Eight incisors, four in each jaw—the four being composed of two central and two lateral incisors—also four canine or cuspid teeth, two in each jaw, and eight molars, four in each jaw—the molars being called first and second molars, indicating their relative positions as well as the periods of their eruption (commonly called cutting). It is generally recognized among physicians that all diseases of children are more difficult to treat during dentition than before or after. It is well enough for parents to recognize this fact in administering medicines to their children. Although the time of eruptions of the teeth differ with different persons, yet the following table gives a close approximation:
ERUPTION OF THE TEETH.
| Deciduous Teeth. | Permanent Teeth. | ||||
| (The lower generally precede the upper by two or three months.) | First molars | 5 to 6 | years | ||
| Central incisors | 6 to 8 | years | |||
| Lateral incisors | 7 to 9 | years | |||
| Central incisors | 5 to 8 | months | First bicuspids | 9 to 10 | years |
| Lateral incisors | 7 to 10 | months | Second bicuspids | 10 to 11 | years |
| First molars | 12 to 16 | months | Canines | 11 to 12 | years |
| Canines | 15 to 20 | months | Second molars | 12 to 14 | years |
| Second molars | 20 to 36 | months | Third molars | 17 to 21 | years |
It would be difficult indeed to condense in so short a space so much practical information from a reliable source as has been given in the following prize essay on the teeth, which was awarded by the Dental Society of Philadelphia: