This article describes fieldwork undertaken in 1972 at the harbour of the Hellenistic city of Ptolemais at Tolmeita in Cyrenaica, Libya. This survey has shown that the city possessed a sophisticated Hellenistic harbour installation, now submerged by some 2 m. It consisted of a small fishing harbour and a larger commercial harbour protected by extensive stone breakwaters built around two offshore islands. Between the harbours, remains were found under water of an extensive block‐built quay connected to one island, where there was a system of submerged rock‐cut tanks. These are interpreted as the foundations of a fish‐processing factory. Changes in sea‐level are also discussed.

The clearance between a compressor or turbine case and rotating blades or shrouds has been measured in a variety of ways over the years with varying degrees of accuracy. However, one critical clearance which has defied active measurement heretofore has been that between the tip of a cantilevered stator vane and an adjacent drum rotor. A significant number of turbomachines under development, representing many millions of dollars, have met an inglorious end through unanticipated rubs which were experienced in this area. The present paper describes how a device which was introduced by its manufacturer for conventional rotor tip or shroud clearance measurements was applied to measure stator-vane-to-drum clearance. The installation technique is explained, and the results of vane-to-drum measurements made with a research compressor are presented. Adaptations of the same technique should permit similar measurements to be made within a turbine, and possibly on rotating seals buried deep within a turbomachine.

On the East coast of Tunisia, between Sousse and Sfax, lie the scant remains of the ancient city of Thapsus, notable mainly for a battle fought in the civil war in 46 BC. Visits by the authors resulted in the discovery of one of the longest‐known harbour moles in the entire Roman Empire. No ancient sources make reference to any work of such magnitude and the paper suggests that the harbour was never completed, but might have been started by the local emperors Gordianus, none of whom survived long enough to have executed such a project.

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The paper describes some of the design solutions that were adopted in the realization of a small two shaft, counterrotating turbine rig. The turbine, for a small space engine technology upper stage liquid propellant rocket turbo pump system, was only 100mm tip diameter with a correspondingly small annulus height. Detailed flow measurements were provided by 3 axis actuators at inlet and outlet of the working section. Torque and Power were measured on each shaft using Radio Frequency (R.F.) telemetry torquemeters. A modular design allowed the rig to be rebuilt rapidly in one and two stage configurations with different blade sets. This enabled the effect of changing turbine configurations to be studied.