Page:Popular Science Monthly Volume 21.djvu/130

122 not also edit the advertisements. We must draw the line somewhere, and we stop at the one hundred and forty-fourth page. We do not think it would be easy to edit the advertisements. If the rule should be, not to publish lies, it would abolish the department, for they are by no means confined to quack medicines. St. Jacob's may he about his "oil," and Aunty Pinkham about her "compound"; but there is this mitigation in such cases, that everybody knows it. The worst difficulty begins with those advertisements in which truth and falsehood are mixed, for

Our correspondent had better address himself to the managers of the advertising department, and convince them that they should not work down to the low standard of the religious and secular press. Meantime we agree not to sandwich advertisements through the text of the "Monthly," as is the custom with some journals. Editors.

Messrs. Editors.

read with great interest the articles you have recently published, explaining improved methods of teaching various branches of science in public schools.

At the opening of this school last September, we found ourselves with a class of a dozen boys and girls from fourteen to eighteen years of age, who were ready to begin the study of natural philosophy. I suppose we might have provided those boys and girls with copies of some one of the many text-books which profess to carry students over the entire subject in "fourteen weeks," or some other incredibly short time; we might have set those students to committing and reciting that text, but we didn't.

After some experimental work with improvised apparatus in illustration of the properties of matter, the students provided themselves with copies of Tyndall's "Lessons in Electricity." We chose that branch of physics rather than any other, because the school owned a set of Tyndall's apparatus especially designed to accompany the "Lessons." The class then began a systematic course of experiment, following, in a general way, the order of their book, but making also many other experiments. The students took turns in conducting the work, and all were enthusiastic. Nothing was taken without proof, and, the better to assure myself of the thoroughness of the work, I had them write up from memory weekly reports of the experiments performed. Of course, our work was slow, but I think it was sure, a real scientific spirit manifesting itself in every member of the class. We have now reached a part of the work where a more powerful electrical machine is necessary, and of course we shall get it. I think it is a mistake to begin with the machine. It is too complicated to be easily understood at first, and the result is a lack of clear ideas. The simple experiments recommended by Professor Tyndall are excellent. They lead the student along so gradually and so surely that when he reaches the explanation of the electrical machine, or the Leyden-jar, he finds very little difficulty.

We have in the school other scientific work than that described above; but this is the one subject where we have the best chance to cultivate accuracy and an interest in scientific methods.

Messrs. Editors.

much discussion concerning the effects of earth-worms upon plants in pots, in regard to their eating the roots of plants, and also the injury their acid excretions may do the plants. Having kept house-plants for many years and in all sorts of vessels, from unglazed earthen pots to glazed delf, and in iron and in tin vessels also, and having had good success without drainage at all, even by having a hole in the vessel, and also having had the earth-worms under consideration, before Mr. Darwin was heard from on the subject, I feel that I may add an item of interest about them. The complaints that I have seen come from florists. Florists, like all other specialists, have notions, and I believe this about earth-worms hurting plants is one. I have found women who, when their house-plants did not thrive, laid it to earth-worms. I do not agree with them nor with the florists, as I do not believe, from nearly twenty years' handling of house-plants, that earth-worms injure pot-plants. I have used all sorts of soil, from good garden to leaf-mold, and have always used well-rotted manure, in which earth-worms abound, to mix with the soil, and, if I can, have had good air, plenty of light, correct temperature, and have watered properly. I have never failed to have a plant thrive, even if the pot was full of worms, and was tin, delf, iron, or unglazed pottery, and I have grown