SOLUTION. 



Use for lessons in solution several common substances: some which 

 dissolve readily in water, as sugar and salt; some which do not dissolve 

 so readily, as camphor, or potassium bichromate; and some that do not 

 dissolve perceptibly, as whiting. Use ameng them some which give a 

 colored solution, such as sulphate of copper, bichromate of potash, or 

 some of the aniline dyes. Have the appearance of the solution careful- 

 ly noted and compared with the mixtures with water when no solution 

 takes place. 



Allow them to evaporate a solution of sugar or salt until the sugar or 

 salt is regained. This may be done in a tin cup, on the stove. If the 

 evaporation is allowed to proceed slowly, beautiful crystals may be 

 formed. A solution of alum in an open jar, left in the school-room in a 

 place where it will not be disturbed, will give beautiful crystals. If 

 strings are suspended in thejar, the crystals will form on the strings, 

 and can then be removed. 



If you have a friend among the druggists, he will no doubt arrange 

 you some sort of solution giving beautiful crystals. There are a num- 

 ber of ways you may devise to show the formation of crystals. 



Another method of making a pretty experiment is to smear a sheet of 

 glass with a solution of some salt, and as the water dries out, the fealt 

 shoots across it in beautiful crystals. Sal ammoniac, sulphate of copper, 

 and common salt will answer. If this process is watched with a micro- 

 scope it is most interesting. For the older pupils, the forms of crystals 

 make an interesting study, and some lessons may be prepared on this 

 later. 



That things dissolved can pass through filters, and those not dissolved 

 cannot pass through, can of course be shown by the use of funnel and 

 filter paper. This conception of dissolved substances is important in 

 the later lessons on how certain foods get into the animal and plant 

 bodies. 



Mushrooms. 



At this time of year, a great number of interesting forms may be 

 found in all sorts of places, and brought in by the children. 



One of the umbrella torms may be used for the first lesson. The fol- 

 lowing names of the parts will be convenient: cap^ stalky plates or gills, 

 and the ring may be given. 



Show where the spores are formed. The spores are the things which 

 answer for its seeds. They are microscopic, and hence cannot be seen 

 by the children. Cut off the cap, place it gill-side down on a sheet of 

 glass. In a few hours, or by the next day the glass will be covered by 

 a dust which comes from the surface of the gills. This dust consists of 

 the spores. They may be seen better if the glass is placed over white 

 or dark paper, according as the color of the spores may be dark or light. 



