Too much light is useless for observing delicately coloured or colourless preparations, whose parts only become visible as a result of slight differences of diffraction.
They are also conical on section from within outwards and from before backwards, this shape converting the pinionsinto delicately graduated instruments balanced with the utmost nicety to satisfy the requirements of the muscular system on the one hand and the resistance and resiliency of the air on the other.
Its characteristics are exceptional tallness combined with slenderness and elegance of figure; a face somewhat long, without any special prominence of the cheekbones but having more or less oblique eyes; an aquiline nose; a slightly receding chin; largish upper teeth; a long neck; a narrow chest; a long trunk, and delicately shaped, small hands with long, slender fingers.
There abound "beautifully laid out gardens, public and private, and solidly constructed roads, some of them bordered with bamboos and other delicately-fronded trees, and fringed with the luxuriant growth of semi-tropical vegetation."
They have a semi-opaque body with an "egg-shell" surface and are delicately tinted with colour.