The first effect of ether is a temporary stimulation of the heart, which beats more rapidly and more strongly, thus raising the blood pressure. This effect is not very prolonged; like all other drug stimulation, it is followed by depression. In the healthy subject properly anæsthetised, such depression is very moderate in degree, and in a normal administration it is probable that the heart, after the first few minutes, is acting very much at its normal speed and force. Ether is, however, a marked vaso-dilator, and the net result upon blood pressure is a slight fall after the first few minutes. If the method in use is “closed,” the pressure remains slightly raised for some considerable time, usually throughout the administration. The slight anoxaemia induces a vaso-constriction; and the CO_{2} excess, in the view of Henderson (_see_ page 10), maintains a good return of venous blood to the heart and a satisfactory cardiac output. For a note of certain blood changes resulting from ether and other anæsthetics (_see_ Appendix III.). Respiratory System. In addition to the effect upon the medullary centre already referred to, ether effects the respiratory tract more profoundly than other anæsthetics. The mucous membranes are irritated, and in some cases there is a great outpouring of mucous. Though usually limited to the upper part of the tract (nose, pharynx, and trachea), the irritation sometimes extends deeply into the chest, affecting even the small bronchioles. These unpleasant effects of ether are in the great majority of cases, quite transient: after the first ten minutes no addition to the secretions is noticed. In a minority, however, the effect persists, the whole chest is filled with moist sounds, and persistence with the drug is impossible. _The kidneys_ are always slightly irritated by ether, and if they are or recently have been subject to inflammatory disease, a very acute exacerbation is apt to follow the use of the drug. In the healthy kidney this is not to be feared, nor does it seem to be an appreciable danger where one kidney is sound, even if the other is the seat of gross organic disease necessitating its drainage or removal. [Illustration: FIG. 23.--Clover’s ether inhaler, with nitrous oxide attachment.] Methods of Administration. Many methods have been tried, but those which at present hold the field are-- (1) Closed Ether. (2) Open Ether, more properly called the Perhalation Method. (3) The “Vapour” Method. (4) The Rectal Method (Gwathmey’s oil-ether). (5) The Intratracheal Method, described separately in Chapter X. [Illustration: FIG. 24.--Diagram of a vertical section through the middle of Clover’s Inhaler. A. shows the ether dome; B. Central tube removed from apparatus] (1) Closed Ether.