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Under deteriorating conditions of travelling in urban areas, especially city centers, prioritization of public transport is one of the main ways of its enhancing. In developed countries sophisticated control traffic systems are being implemented while in developing countries such solutions due to implementation cost are very rare. The purpose of this paper is to assess public transport operational effectiveness under diverse operational schemes present in two similar in size and traffic characteristics cities. The assessment is based on average journey times and speeds during peak and off peak hours.

The methodology includes measurements and estimates of bus rides through in-field measurements in Edinburgh, UK and in Bialystok, Poland. In-field evaluations have been conducted using average speed and travel times. The data were collected by utilizing a portable GPS data logger that allowed monitoring and recording bus position along tested streets in one second intervals. Traffic optimization in Edinburgh is provided by separated bus lanes and control urban traffic system while in Bialystok the only prioritization is supported by bus lanes. The research areas in Edinburgh and in Bialystok covered streets in city centers and adjacent districts.

The findings show large operational potential in developing separated bus lanes in city centers of developing countries when due to cost they cannot afford implementing advanced ITS solutions. The introduction of bus lanes should be proceeded even at the expense of individual users. It has been found that well developed road network in city center with separated bus lanes can provide operating speed at comparable levels to speed of buses operating along lower volume corridors.

The comparison of bus lanes working under different traffic management conditions was carried out. Conducted analyses showed great potential of proper planning strategy of road network development toward the improvement of public transport performance.

THOUGH rockets have aroused a good deal of public interest during the last few years and a great number of very interesting books and articles have been published about the theoretical side of this new science, little is generally known about the experimental progress that has been made, especially in Germany and the U.S.A. In describing this science—the Americans call it “rocketry”—as “new,” it is to be understood that this term applies only to the mathematics of it. The ordinary powder or “sky” rocket is by no means new, but has a long and very involved history, going back to Hassan Alrammah, called “nedshm‐eddin” (The Faithful) in A.D. 1280, who designed the first rocket‐driven torpedo. But though rockets in general (i.e. the powder rocket, which alone existed previous to 1929) have a history of almost a millennium and have even been of historical importance (Sir William Congreve's war‐rockets), the manufacturers of powder rockets knew nothing about their mathematics. When, for example, in 1928 the German Verein für Raumschiffahrt discussed the problem of exhaust velocities and impulses, its president, Johannes Winkler, asked the largest rocket factories about this information and received the answer that they did not know it and had no way of determining it. Winkler was therefore obliged to take the thrust‐diagram of a powder rocket himself (Fig. 1). This diagram revealed that the thrust of a sky‐rocket lasts for only two‐tenths of a second; this result was really amazing and the most amazed were the manufacturers of these rockets.