Some preliminary measurements have been made of the windage loss in a number of larger spur gears and one helical gear, in air, and of how this windage loss is affected by speed, size, details of the gear geometry and the shape of enclosures. It is shown that for most gears the larger part of the windage loss arises from the teeth. Some comments are made on the mechanisms of windage loss and an empirical formula is given to estimate roughly the windage loss to be expected from a gear. The experiments, however, were carried out in air and there is a lack ofknowledge on the efSects of oil vapour, mist and larger drops in the atmosphere on the windage loss. NOTATIOND root diameter, mm F face width, mm M tooth module, mm N rotational speed, r/min P windage power loss, kW 0263-7138/84 $2.00 + .05 Proc Instn Mech Engrs Vol 198A No 1 4/84 0 IMechE 1984 at UNIV OF PITTSBURGH on June 22, 2015 pia.sagepub.com Downloaded from * A 760 mm didmeter 8 mm module model shed its teeth at around IS00 r/mm Proc Instn Mech Engrs Vol 198A No 1

Summary. A brief description of the islands is followed by an account of the 13 surviving endemic land‐birds, based largely on the results of the Bristol Seychelles Expedition 1964–65. The whole of the Seychelles avifauna could possibly be derived from Madagascar, but anomalous distributions suggest that some species colonized the Seychelles from the northeast, either en route for Madagascar, or independently of the Madagascan colonists. The Seychelles birds show insular evolutionary characteristics in colour and size, and some are extremes of their taxa. Endemic and introduced birds are listed in the appendix, with a Summary of their present and former distributions. A list of vagrant land‐birds is included.

[1] Very-long-period (VLP) pulses with period of 6-7s, displaying similar waveforms, were identified in 1998 from broadband seismographs around the summit crater. These pulses accompanied most of multiphase (MP) earthquakes, a type of long-period event locally defined at Merapi Volcano. Source mechanisms for several VLP pulses were examined by applying moment tensor inversion to the waveform data. Solutions were consistent with a crack striking $70°and dipping $50°SW, 100m under the active dome, suggest pressurized gas transport involving accumulation and sudden release of 10-60 m 3 of gas in the crack over a 6s interval.

No abstract

No abstract