Here belongs, on the other hand, technological knowledge, acquired partly through direct observation, partly through lessons in descriptive physical science. Technology ought not to be considered merely from the side of the so-called material interests. It furnishes very important connecting links between the apprehension of the facts of nature and human purposes. Every growing boy and youth should learn to handle the ordinary tools of the carpenter as well as rule and compasses. Mechanical skill would often prove far more useful than gymnastic exercises. The former benefits the mind, the latter benefit the body. With burgher schools should go manual training-schools, which does not mean that the latter must necessarily be trade schools. Finally, every human being ought to learn how to use his hands. The hand has a place of honor beside language in elevating mankind above the brute. The foregoing store of information also enters into the study of geography; how, will appear in the next chapter. The soundness of the foregoing remarks is witnessed by the rapid development of manual training-schools in the last decade, and the almost universal desire, if not practice, of providing considerable amounts of manual training for the pupils of the grammar grades. The girls usually have some form of sewing and cooking, while the boys have sloyd or other similar tool work in wood. The _rationale_ of requiring girls to do carpenter work instead of the forms of manual exercise that especially pertain to their sex is not yet satisfactorily established. 260. On the observation of the heavenly bodies is based popular astronomy, which provides a test as to whether the mathematical imagination has been properly cultivated. 261. Elementary statics and mechanics will serve as an early introduction to physics, which combines with the easiest portions of chemistry. Long before physics is formally presented, it must be foreshadowed by many things stimulating the attention. Notice is directed to clocks, mills, the most familiar phenomena of atmospheric pressure, to electrical and magnetic toys, etc. In burgher schools, at least, so much must be said about buildings and machines as is necessary to incite to further study in the future. The same holds for the fundamental facts of physiology. 262. As often as a new topic for study is introduced, it is important to give prominence to some of the salient facts, and these must be accurately memorized. Moreover, pupils need to have practice in exact description. Where practicable, these descriptions are corrected by actually looking at the objects themselves.