(Table I.), will observe that in some cases where the breathingcapacity is small, the extreme costal motion is considerable, while in others, where the capacity is great, the extreme costal motion is comparatively but little. I do not doubt, however, that, if a sufficient number of cases were collected, it would be found that the extreme respiratory motions, as indicated by the chest-measurer, will, as a general rule, agree with the sound and important conclusions to which Dr. Hutchinson has arrived with regard to the breathing-capacity and the influence upon it of height, mobility of chest, age, weight, and other circumstances.

One thing is certain, that the extreme range of motion may vary considerably in persons whose chest and general system are perfectly sound. This is, I take it, in great part due to the inability of many persons, when recumbent, to inspire and expire deeply when directed so to do. In practice we shall find that healthy persons when recumbent may have a range of extreme respiratory motion varying from one-half or three-quarters of an inch to about an inch and a half, or even two inches.

The various ribs have nearly the same amount of motion during extreme respiration, but the lateral motion of each rib is less than its anterior motion. The extent of motion of the diaphragm is about the same as that of the ribs, since it descends about an inch; and that of the abdomen, between the lower end of the sternum and the umbilicus, is also about an inch, sometimes more and sometimes less.

The motion of the lower or diaphragmatic ribs and the eighth rib, which in tranquil breathing is greater, is in extreme respiration less than that of the thoracic ribs.

Many persons in perfect visceral health, affected with pain or injury, or some peculiarity of constitution, have an ordinary costal expansion of 08 to 12 or 14 in. in such persons the diaphragmatic motion is from 20 to 25 in., and the motion of the diaphragmatic ribs and the eighth ribs, instead of being greater, is often only equal to or even less than that of the thoracic ribs. (Table, Cases 28-37.)

In one man-Clay-(Table I., Case 30)-who had suffered from sciatica, the breathing, instead of being natural, was rather a succession of irregular sighs about nine in the minute; the second ribs had during inspiration a motion varying from 1 to 2 in., the abdominal muscles (diaphragm) advanced 9 in. to 1 in., and the eighth and diaphragmatic ribs moved outwards from 3 to 4 in. In extreme inspiration the second rib advanced 1 in., and the abdomen (diaphragm) 1·60 in.

Respiratory Movements in Boyhood and Old Age.

In boys the cartilages are more flexible, and the costal mobility is greater than in adults. The extreme costal motion is in them greater in proportion to their breathing-capacity than in adults. Thus in Coupe, (Table I., Case 25,) aged 11, whose height was 4 ft. 7 in., and breathing-capacity only 110 cubic inches, the ordinary movement of the second rib was '06 in. and the extreme movement 1.30. Some boys, especially if they have been long in bed, have very little command over their inspiratory muscles, and in them the extreme movement may be slight. In Greenfield, (Table I., Case 27,) for instance, a boy of 10 years of age, pale, having a diseased knee, but whose chest was healthy, the ordinary motion of the second rib was '03 in., and sometimes 0, and the extreme motion ⚫3 in. Such boys, besides their irregular volition, are manifestly out of practice in the complete action of their ribs.

In old age (Table I., Cases 38-44) each cartilage is ossified, forming with the rib one unbending piece. The costal motion is carried on by the lateral anterior and posterior thrust of the solidified rib and cartilage; and in old men, owing to the non-yielding of the cartilages, the advance of the sternum, both during ordinary and extreme inspiration, is often greater than that of the second rib. In this respect old age differs remarkably from boyhood, when, owing to the great flexibility of the cartilages, the costal advance is greater than the sternal.

For the same reason, namely, the completion into one un

yielding piece of the rib and cartilage in the aged, the lower end of the sternum, owing to the sixth and seventh ribs being longer than the second, usually advances more than the upper portion; while in youth, owing to the flexibility of the cartilages, the upper portion of the sternum usually advances more than the lower end.

In the aged, the lateral motion of the sixth rib is increased, during both ordinary and deep inspiration, while that of the diaphragmatic ribs is diminished.

The ordinary diaphragmatic breathing of the aged is rather above the average, being from 3 to 5 in., but its extreme movement is not remarkable.

The difference both in the ordinary and extreme respiratory movement of the left diaphragmatic and intermediate sets of ribs, as compared with the right, is usually more marked in old age than in youth.

In the adult period of life the younger man has more often those varieties of costal motion characteristic of the boy, and the older man more often those of old age.

Influence of Height on the Respiratory Motions.

Height has a perceptible influence on the extreme costal motion, following the important law laid down by Dr. Hutchinson, that the breathing-capacity increases with the height.

I feel convinced of the soundness of Dr. Hodgkin's view that the increased capacity with height is in great part due to the increased length of the dorsal portion of the spinal column. The long-bodied dwarf given by Dr. Hutchinson at p. 184 does not really militate against this view, as that man is evidently a deformity.

An additional reason for the greater capacity of the tall is, I conceive, the greater length of their ribs as well as of their other bones. If so, in the narrow-chested tall man of great breathing-capacity, the ribs will be more oblique than in a short man whose chest is of equal diameter but whose capacity of breathing is smaller. In such a case, the tall man will have a

greater range of motion of his ribs, just as he has of his thighs when he raises them.

Respiratory Movements in the Healthy Female.

In the adult female, the form of the chest and abdomen, and the respiratory movements, are often undoubtedly modified by tight lacing.

The form of the chest and the respiratory movements do not differ perceptibly in girls and boys below the age of 10. Although the form of the chest remains nearly the same until the age of 12, the abdominal movement is then somewhat less, and the thoracic, somewhat greater, in girls than boys. At this age, and earlier, stays are worn; and though they do not compress the body materially, yet they restrain the free expansion of the lower ribs during brisk exercise. After the age of 14 the form of the chest and the respiratory movements differ materially in females and males. The transverse diameter of the chest from seventh rib to seventh, instead of being greater than that from fifth rib to fifth, as it is in males, is in females considerably less. This difference is greater or less, in proportion as the stays are worn more or less tight. There is a great difference in the respiratory movements, when the stays are on, and when they are off. When they are on, the thoracic movement is very much exaggerated, the second ribs then moving forward from 06 to 2 in., while when they are off, they only move forward from '03 to 1 in. On the other hand, the movements of the lower ribs and diaphragm are much more restrained when the stays are on (the abdominal movement being then '06 to 11 in.), than when they are off (the abdominal movement being then from 08 to 2 in.). During a deep inspiration the disproportion in the abdominal movement, or rather that at the so-called waist, is still greater, being about .1 in. when the stays are on, and from 15 to 4 in. when they are off. The difference at the waist, when measured with the tape, is very striking, the increased measurement during an extreme inspiration being '05 to 3 in. when they are on, and from 6 to 1.5 in. when they are off. I have found the

circumference at the waist from one to two inches less when the stays were worn than when they were taken off.*

These observations render it certain that the wearing of stays materially influences the respiratory movements, lessening the movement of the diaphragmatic ribs, and exaggerating

• The form of the chest in Ann Winfield, aged 6, (Table I., Case 52,) and Eliza Elsom, aged 11, (Table I., Case 49,) did not materially differ from that in boys of about the same age and size; and in M. Daft, aged 17, (Table I., Case 48,) but whose form and development was that of a girl of 14, the difference in form was inconsiderable.

In Winfield, during inspiration, the

upper end of the sternum advanced '05 in.; the abdomen 25 in. In Elsom, the second rib advanced

•10

⚫06

⚫20

•18 to 20

In Daft Elsom and Daft both wore stays, and though the stays were loose, yet I conceive that their influence upon the chest had already commenced.

Jane Goodall, aged 33, (Table I., Case 45,) had at one time worn very tight stays; in her, while the lower part of the chest over the intermediate and diaphragmatic ribs was remarkably compressed, the seventh costal cartilages of the opposite sides below the sternum, being pressed near each other, the upper part of the chest was excessively developed. The diameter of the chest from side to side was from fifth rib to fifth rib 10.2 in., and from eighth rib to eighth rib 9-5 in. Compare this with Elsom's chest, in which these measurements were respectively 8.4 and 8.6 in., and with Daft's, in whom the influence of stays was more pronounced, and in whom the measurements were respectively 9.5 in. and 9.3 in.

In Goodall the second rib advanced, during each ordinary inspiration with stays on 12 to 2 in., and the abdomen 08 in., (as well as it could be ascertained,) and the waist expanded during the deepest possible inspiration onlyth of an inch. When she had her stays off, the second rib advanced 06 to 08 in., the abdomen 12 to 2 in., and the extreme expansion of the waist was about 1 in.

In Eliza Ball, aged 25, (Table I., Case 47,) who had always worn loose stays, the chest was not so excessively full above and contracted below, as was that of Goodall; the upper and lower diameter being respectively 11.7 in. and 11.2 in. The motion of the second rib with stays on was '05 to 11 in.; with the stays off 12 to 25 in. In Ball, though the stays were loose, they prevented the full expansion of the lower ribs during a deep inspiration; since, when they were on, the extreme expansion of the waist wasths of an inch, and when they were off, an inch and a half. Here, although the stays were loose, there was an inch of compression, and the expansion, which ought to have been an inch and a half, was only ths of an inch.

In Julia Green, (Table I., Case 45,) the amount of compression from stays was two inches, although the stays were not so tight as usual.