The tenth abdominal segment carries strong, unjointed cerci, while the presence of reproductive armature on the second abdominal segment of the male is a character found in no other order of the Hexapoda.
Siemens effected a great improvement by inventing a shuttle armature and improving the shape of the field magnet.
On the technical side the invention of a new form of armature for dynamo electric machines by Z.
The torque acting on the armature of an electric motor is necessarily accompanied by an equal and opposite torque acting on the FIG.
The experiments with this form were not successful, and, with the view of making the moving parts as light as possible, he substituted for the comparatively heavy lever armature a small piece of clock spring, about the size of a sixpence, glued to the centre of the diaphragm.
The development of the armature has been little studied, and the question whether there may be present gonapophyses homologous with those of the female is open.
This instrument was capable of giving very considerable speed, but it was more complicated than that now in use, which consists only of an electromagnet, with its armature lever arranged to stop against an anvil or screw in such a way as to give a distinct and somewhat loud sound.
An axle carrying four cams is normally at rest, but it is thrown into gear with the mechanism when the armature rises, makes one complete revolution, and comes to rest ready for the next signal.
The armature is immersed in a shallow vessel filled with mercury, which is insulated from the vessel and the armature, except at the ends of the copper strips.
In most of the systems that have been proposed this result is attained by electrical regulation; in one, however, a mechanical method is adopted, the dynamo being so' hung that it allows the driving belt to slip when the speed of the axle exceeds a certain limit, the armature thus being rotated at an approximately constant speed.