An actress of as great promise as any that has appeared on the British theatre in the memory of man, has lately come forth at Covent Garden, in the arduous character of Lady Macbeth, in which, if we are to trust the London critics, she at once started to a level with Mrs. Siddons. Her name is Smith. She has, like Mrs. Siddons, been on the stage from childhood, without being noticed by any but the happy few, some of whom augured highly of her from the first, and she has fully accomplished their prognostications. The first impressive trace we find of her in theatrical annals is in an Edinburgh criticism. “As I think most highly of this juvenile performer,” says that writer, “and entertain most sanguine hopes of seeing her soon at the head of her profession, I will not insult her by indiscriminate panegyric or mawkish praise. Her comedy is by no means satisfactory to me. The disadvantage of a _petite_ figure is not, in this department compensated by any high excellencies. Her comedy is generally speaking, rather meagre and unadorned, and in a degree pointless and ineffective.--But her tragedy merits every praise. In richness and variety of tone; in propriety and justness of action and gesture; in picturesque and impressive attitude, in a nervous mellowed modulation; in appropriate deportment--above all in the discriminating delicacy of taste, by which she distinguishes and expresses the feelings and workings of the heart, she is above praise.” Miss Smith next meets us in London in 1808, playing lady Macbeth at Covent Garden, and is spoken of as follows: