Still, what the observer wants is not merely confirmation of the statement that Venus exhibits phases. The physical features of a planet are always the most interesting, and here Venus disappoints. That very brilliant lustre which makes her so beautiful an object to the naked eye, and which is even so exquisite in the telescopic view, is a bar to any great progress in the detection of the planet's actual features. For it means that what we are seeing is not really the surface of Venus, but only the sunward side of a dense atmosphere--the 'silver lining' of heavy clouds which interpose between us and the true surface of the planet, and render it highly improbable that anything like satisfactory knowledge of her features will ever be attained. Newcomb, indeed, roundly asserts that all markings hitherto seen have been only temporary clouds and not genuine surface markings at all; though this seems a somewhat absolute verdict in view of the number of skilled observers who have specially studied the planet and assert the objective reality of the markings they have detected. The blunting of the South horn of the planet, visible in Mr. MacEwen's fine drawing (Plate X.), is a feature which has been noted by so many observers that its reality must be conceded. On the other hand, some of the earlier observations recording considerable irregularities of the terminator (margin of the planet between light and darkness), and detached points of light at one of the horns, must seemingly be given up. Denning, one of the most careful of observers, gives the following opinion: 'There is strong negative evidence among modern observations as to the existence of abnormal features, so that the presence of very elevated mountains must be regarded as extremely doubtful.... The detached point at the South horn shown in Schröter's telescope was probably a false appearance due to atmospheric disturbances or instrumental defects.' It will be seen, therefore, that the observer should be very cautious in inferring the actual existence of any abnormal features which may be shown by a small telescope; and the more remarkable the features shown, the more sceptical he may reasonably be as to their reality. The chances are somewhat heavily in favour of their disappearance under more favourable conditions of seeing. [Illustrations (2): PLATE X. Venus. H. MacEwen. 5-inch Refractor.]