The 19th Century Gentleman - The Etiquette of Greeting

"To a casual acquaintance you may bow without speaking; but to those with whom you are well acquainted greater cordiality is due. A bow should always be returned; even to an enemy it is courtesy to return his recognition."
Hill's Manual of Forms, 1873

"Between gentlemen, an inclination of the head, a gesture of the hand, or a mere touching of the hat is sufficient; but in bowing to a lady, the hat must be lifted from the head." "The body is not bent at all in bowing; the inclination of the head is all that is necessary"
Our Deportment, 1881

"In meeting a lady it is optional with her whether she shall pause to speak. If the gentleman has anything to say to her, he should not stop her, but turn around and walk in her company until he has said what he has to say, when he may leave her with a bow and a lift of the hat."
Our Deportment, 1881

"One should always recognize lady acquaintances in the street, either by bowing or words of greeting, a gentleman lifting his hat. If they stop to speak, it is not obligatory to shake hands. Shaking hands [between a lady and gentleman] is not forbidden, but in most cases it is to be avoided in public."
Our Deportment, 1881

"If...you have been introduced to a person whose acquaintance you do not desire, you may merely make the formal bow of etiquette when you meet him, which, of itself, encourages no familiarity; but the bow is indispensible, for he cannot be thought a gentleman who would pass another with a vacant stare, after having been formally presented to him... What is called 'cutting' another is never practiced by gentlemen or ladies, except in some extraordinary instances of bad conduct on the part of the individual thus sacrificed"
Martine's Handbook, 1866