It provides, in the case of new houses in new streets, for an open space in the rear, exclusively belonging to such building, of at least 150 square feet, free from erections except W.C. and ashpit. Where the ground storey is not inhabited, this open space may be provided at a height of 16 feet above the level of the pavement. The open space must extend the entire width of the building and have a depth of 10 feet at least. A diagonal line drawn from the rear of the open space on the pavement level, and inclining towards the building at an angle of 63°·5, shall clear the top of such building save chimneys, dormers, gables, &c. This means that the house may be at all levels twice as high as the space is deep. When a house abuts at the rear on a street or permanent 'open space,' then no private open space or curtilage need be provided. 'Nothing in this section shall apply to houses abutting in the rear on the river Thames, or on a public park, or on an 'open space' of not less than 80 feet in depth which is dedicated to the public, or the maintenance of which as an open space is secured permanently or to the satisfaction of the Council by covenant or otherwise.' In new streets less than 50 feet wide no house may be erected having a height greater than the width of the street. No house may be more than 80 feet high without the special permission of the Council. These regulations, from the point of view of health, are as bad as can be, because they put a premium, so to say, on buildings of enormous cubic capacity. We have seen that the provisions as to private curtilage are limited to a back yard 10 feet deep, but in the case of houses abutting on two streets, front and back, or abutting on a street and 'open space' 80 feet deep, these restrictions are dispensed with.