breastbone?

7. What is the use of the marrow in the bones?

8. Why is the shoulder so often put out of joint?

9. How can you tie a knot in a bone?

10. Why are high pillows injurious?

11. Is a stooping posture a healthful position?

12. Should a boot have a heel piece?

13. Why should one always sit and walk erect?

14. Why does a young child creep rather than walk?

15. What is the natural direction of the big toe?

16. What is the difference between a sprain and a fracture? A dislocation?

17. Does the general health of the system affect the strength of the
bones?

18. Is living bone sensitive? _Ans_.--Scrape a bone, and its vessels
bleed; cut or bore a bone, and its granulations sprout up; break a bone,
and it will heal; cut a piece away, and more bone will readily be
produced; hurt it in any way, and it inflames; burn it, and it dies. Take
any proof of sensibility but the mere feeling of pain, and it will answer