As the upshot, a number of other significant properties besides the first of blood-pressure raising, have been put down to its credit.

Thus, though the force of the heart and the general average blood-pressure remain the same, the state of the circulation may be very different in different parts of the body.

The blood-pressure on the delicate capillary walls causes the exudation of the watery portions of the blood through the cell walls into the capsule.

Thus whatever raises the blood-pressure in the capillaries of the capsules, will increase the quantity of fluid filtering through them.

So anything which lowers the blood-pressure will diminish the watery portion of the secretion, that is, the secretion will be scanty, but concentrated.

Thus, some strong emotion, like fear or undue anxiety, increases the blood-pressure, drives more blood to the kidneys, and causes a larger flow of watery secretion.

The blood-pressure in the kidneys is not only diminished, but the total quantity passing through them in a given time is much lessened.