would seem that even if our means of direct conversion is not so economical as the dynamo yet if it have any reasonable efficiency and is simple of construction it would supplant the older method.In August ofMr. Edison read before the American Association for the Advancement of Science a paper on pyromagnetic generators. Briefly the principle on which his machine was built is this. If a piece of iron wrapped with wire be put between the poles of a magnet a number of lines of force will pass through it and therefore through the coils of the wire depending directly on the strength of the magnet and on the magnetic permeability of the iron. Now it is well known that the permeability of iron becomes very nearly zero when Nike Air Max it is raised to a bright red heat: so if we heat the iron the lines of force through it will decrease and this decrease will cause an electromotive force in the coil of wire. When the iron cools there will be an increase of lines of force causing an electromotive force in the opposite direction. Mr. Edisons machine built on this principle consists Christian Louboutin Outlet of eight horseshoe magnets arranged in a circle the poles facing inward ; and between the poles of each is a roll of thin laminated iron covered with Christian Louboutin Outlet asbestos and wrapped with wire: we will call these the armatures. This is placed over a furnace and beneath it revolves a halfcircle of fireclay which shields half of the armatures from the heat. If this shield be turned continuously half of the armatures are being heated while the other half are being cooled; and the electromotive forces in the two halves which would be in opposite directions are added by a commutating arrangement on the shaft of the shield. A blast of cold air assists the cooling of the armatures.heat into motion the latter transforming the energy of motion into electrical energy.Both the pyromagnetic generators of Mr. Edison and M. Menges are an advance on previous machines of this type. It is Nike Australia difficult to see however how in their present form either can produce any very considerable quantity of Nike Shoes Australia electrical energy with any reasonable size of apparatus. The publication of reliable figures on the performance of these machines would be of great interest.SPRAGUEELECTRICRAILWAYINRICHMOND. There was opened for traffic on Feb.an electric streetrailroad that from the extent of the plant the difficulties overcome and the perfection of equipment marks a decided advance in electric traction. The Union Passenger Railway system in Richmond extends from the eastern to the western part of the town having a total length of track of eleven miles. The road has many curves of short radius. There are grades that reach ten per cent while there are combinations of curves and grades even more difficult Coach Outlet Store Online than the steepest of the grades. In one case there is a thirtyfoot curve on an ascent of seven percent. In addition to this but a small part of the length is through paved streets and in wet weather the mud is so bad that in some places it completely covers the rails. The road is equipped with forty large sixteenfoot cars. Beneath each car are two horse power motors one Coach Outlet Store Online geared to each pair of wheels. The current is taken from an overhead wire by a wheel or trolley of sheet brass Nike Air Max 90 fixed on the end of a rod which holds it up underneath of and in contact with the wire. This rod is fixed on trunnions and is fitted with springs that give a gentle pressure at the contact. The motors nominally horse power Coach Outlet Store Online each are capable of developing over tenhorse power when necessary. They are beneath the car out of sight and are geared by a system of spurgears to the