In spite of our oft-repeated advice to correspondents in regard to the care necessary in addressing the letters they send, as well as to give their own address in full, we receive communications constantly from boys and girls who are the recipients of letters they can not answer, as the sender has given only his name, and neither the town nor State in which he lives, and in many cases no signature whatever. The young exchangers who receive these unsigned epistles are so honorable as to feel much distressed because they can make no acknowledgment of the favor, and request help from the Post-office Box in obtaining the address of their negligent correspondent. We can not give up space to the rectification of these acts of carelessness, and the writer of the unsigned letter will realize, when he receives no answer, that inattention will surely bring its own penalty.
Redmyre, Sydney, New South Wales, Australia.
I am a little girl twelve years old. I am going to write this letter all by myself. I go to school with three other little girls. Last Thursday night we all went to see the Juvenile Pinafore. All who acted were children, and we enjoyed it very much. We are having Michaelmas holidays just now (September 28).
I tried Nellie H.'s and Sadie McB.'s recipes for candy, and I liked them very much. I send a recipe for sugar-biscuits: Mix together a pound of flour, six ounces of butter, two tea-spoonfuls of baking powder, half a pound of sugar, three eggs, and a pinch of salt. Mix well the flour, sugar, powder, and salt, rub in the butter, then add the eggs, well beaten. Add enough milk to make a dough. Roll it out thin, cut it into small round biscuits, and bake in a hot oven.
I like Young People very much. We never get it here until a month after it is printed.
Gertie R.
Dresden, Saxony.
My young friends, if you would like to make glass slides for your magic lanterns, I will tell you how to put any drawing you wish on the glass. Take a glass of the required size, put a thin layer of wax on it, and after having heated it for a while over a candle flame draw the figures or landscapes in the wax with a knife point or a pointed stick until your instrument touches the glass. Then take a lead vessel with an opening almost as large as your piece of glass. Put into this vessel a small quantity of fluoride of calcium, and mix it with sulphuric acid. When this is all prepared cover the lead vessel with the glass plate, the waxed side downward, and heat the vessel a little. While heating it you will perceive bitter-smelling vapors of hydrofluoric acid, which come in contact with the glass where the wax has been scraped off. After about fifteen or twenty minutes take away the plate, heat it, and wipe off the wax. You can also wash it off with spirits of wine. When the glass is cleaned you will find your drawing engraved on it, and you may afterward color the design to suit your taste.
One thing must not be overlooked. When you try this chemical experiment, do not inhale the vapors of the hydrofluoric acid, for they are very injurious, and burn the skin very badly. Always experiment in a room to which plenty of fresh air has free access.
I wish you much success, and hope you may thus have some pleasant hours during the coming winter days. If any one of you knows some other experiment, I should be ever so glad to see it in the Post-office Box.
Louis G. E.
We hope the members of our Young Chemists' Club, who will no doubt try this pretty experiment, will not overlook for an instant the dangerous qualities of the chemicals, and bear constantly in mind the caution given by the correspondent, as a little carelessness might lead to very serious trouble. If Louis G. E. knows any easy method of coloring the glass slides for a magic lantern so that the paint will be sufficiently transparent and yet firmly set on the glass, he would confer a favor upon many readers of Young People by describing it.