The Special Senses : Part 3

Hygienic Physiology: with Special Reference to the Use of Alcoholic Drinks and Narcotics
by Joel Dorman Steele, Ph.D.

(Page 10 of 13)

Care of the Eyes. - The shape of the eye can not be changed by rubbing and pressing it, as many suppose, but the sight ma. Therefore be fatally injured. Children troubled by nearsightedness should not lean forward at their work, as thereby the vessels of the eye become overcharged with blood. They should avoid fine print, and try, in every possible way, to spare their eyes. If middle age be reached without especial difficulty of sight, the person is comparatively safe. Most cases of squinting are caused by longsightedness, the muscles being strained in the effort to obtain distinct vision. In childhood, it may be cured by a competent surgeon, who will generally cut the muscle that draws the eye out of place.

After any severe illness, especially after measles, scarlatina, or typhoid fever, the eyes should be used with extreme caution, since they share in the general debility of the body, and recover their strength slowly. Healthy eyes even should never be used to read fine print or by a dim light. Serious injury may be caused by an imprudence of this kind. Reading upon the cars is also a fruitful source of harm. The lens, striving to adapt itself to the incessantly varying distance of the page, soon becomes wearied. Whenever the eyes begin to ache, it is a warning that they are being overtaxed and need rest.

Objects that get into the eye should be removed before they cause inflammation; rubbing in the meantime only irritates and increases the sensitiveness. If the eye be shut for a few moments, so as to let the tears accumulate, and the upper lid be then lifted by taking hold of it at the center, the cinder or dust is often washed away at once. Trifling objects can be removed by simply drawing the upper lid as far as possible over the lower one; when the lid flies back to its place, the friction will detach any light substance. If it becomes necessary, turn the upper lid over a pencil, and the intruder may then be wiped off with a handkerchief. "Eye-stones" are a popular delusion. When they seem to take out a cinder, it is only because they raise the eyelid, and allow the tears to wash it out. No one should ever use an eyewash, except by medical advice. The eye is too delicate an organ to be trifled with, and when any disease is suspected, a reliable physician should be consulted. This is especially necessary, since, when one eye is injured, the other, by sympathy, is liable to become inflamed, and perhaps be destroyed.

When reading or working, the light should be at the left side, or at the rear; never in front.

The constant increase of defective eyesight among the pupils in our schools is an alarming fact. Dr. Agnew considers that our schoolrooms are fast making us a spectacle-using people. Nearsightedness seems to increase from class to class, until in the upper departments, there are sometimes as high as fifty per cent of the pupil. Therefore afflicted. The causes are (1), desks so placed as to make the light from the windows shine directly into the eyes of the scholars; (2), cross lights from opposite windows; (3), insufficient light; (4), small type that strains the eyes; and (5), the position of the pupil as he bends over his desk or slate, causing the blood to settle in his eyes. All these causes can be remedied; the position of the desks can be changed; windows can be shaded, or new ones inserted; books and newspapers that try the eyes can be rejected; and every pupil can be taught how to sit at study.

Practical Questions

1. Why does a laundress test the temperature of her flatiron by holding it near her cheek?

2. When we are cold, why do we spread the palms of our hands before the fire?

3. What is meant by a "furred tongue"?

4. Why has sand or sulphur no taste?

5. What was the origin of the word palatable?

6. Why does a cold in the head injure the flavor of our coffee?

7. Name some so-called flavors that are really sensations of touch.

8. What is the object of the hairs in the nostrils?

9. What use does the nose sub serve in the process of respiration?

10. Why do we sometimes hold the nose when we take unpleasant medicine?

11. Why was the nose placed over the mouth?

12. Describe how the hand is adapted to be the instrument of touch.

13. Besides being the organ of taste, what use does the tongue sub serve?

14. Why is not the act of tasting complete until we swallow?

15. Why do all things have the same flavor when one's tongue is "furred" by fever?

16. Which sense is the more useful - hearing or sight?

17. Which coat is the white of the eye?

18. What makes the difference in the color of eyes?

19. Why do we snuff the air when we wish to obtain a distinct smell?

20. Why do red-hot iron and frozen mercury (-40°) produce the same sensation?

21. Why can an elderly person drink tea which to a child would be unbearably hot?

22. Why does an old man hold his paper so far from his eyes?

23. Would you rather be punished on the tips of your fingers than on the palm of your hand?

24. What is the object of the eyelashes? Are the hairs straight?

25. What is the use of winking?

26. When you wink, do the eyelids touch at once along their whole length? Why?

27. How many rows of hairs are there in the eyelashes?

28. Do all nations have eyes of the same shape?

29. Why does snuff taking cause a flow of tears?

30. Why does a fall cause one to "see stars"?

31. Why can we not see with the nose, or smell with the eyes?

32. What causes the roughness of a cat's tongue?

33. Is the cuticle essential to touch?

34. Can one tickle himself?

35. Why does a bitter taste often produce vomiting?

36. Is there any danger in looking "cross-eyed" for fun?

37. Should schoolroom desks face a window?

38. Why do we look at a person to whom we are listening attentively?

39. Do we really feel with our fingers?

40. Is the eye a perfect sphere?

41. How often do we wink?

42. Why is the interior of a telescope or microscope often painted black?

43. What is "the apple of the eye"?

44. What form of glasses do old people require?

45. Should we ever wash our ears with cold water?

46. What is the object of the winding passages in the nose?

47. Can a smoker tell in the dark, whether or not his cigar is lighted?

48. Will a nerve reunite after it has been cut?

49. Will the sight give us an idea of solidity?

50. Why can a skillful surgeon determinate the condition of the brain and other internal organs by examining the interior of the eye?

51. Is there any truth in the idea that the image of the murderer can be seen in the eye of the dead victim?

52. What is the length of the optic nerve? About three fourths of an inch.

53. Why does an injury to one eye generally affect the other eye? The optic nerves give off no branches in passing from their origin in two ganglia situated between the cerebrum and the cerebellum, and their termination in the eyeballs; but, in the middle of their course, they decussate, or unite in one mass. The fibers of the two nerves here pass from side to side, and intermingle. The two ganglia are also united directly by fibers. Therefore the eyes are not really separate organs of sight, but a kind of double organ to perform, a single function.