We report the observation of an intense gamma‐ray burst observed on the ground at sea level, produced in association with the initial‐stage of rocket‐triggered lightning at the International Center for Lightning Research and Testing at Camp Blanding, FL. The burst was observed simultaneously on three NaI(Tl)/photomultiplier tube detectors that were located 650 m from the triggered lightning channel with gamma‐ray energies extending up to more than 10 MeV. The burst consisted of 227 individual gamma‐rays that arrived over a 300 μs time period in coincidence with an 11 kA current pulse. The burst of gamma‐rays had very different characteristics from the x‐ray emission frequently seen in association with the dart leader/return stroke sequences of triggered lightning and may represent a new kind of event, likely originating from cloud processes thousands of meters overhead.

[1] We report measurements of the x-ray emission from rocket-triggered lightning, made during the summer of 2003, using four instruments placed between 15 and 40 m from the lightning channels. X-rays were measured 0 -80 ms just prior to and at the beginning of 73% of the 26 return strokes observed. The emission was composed of multiple, very brief bursts of x-rays in the 30-250 keV range, with each burst typically lasting less than 1 ms. The x-rays were primarily observed to be spatially and temporally associated with the dart leaders with a possible contribution from the beginning of the return strokes, with the most intense x-ray bursts coming from the part of the lightning channel within $50 m of the ground. Because triggered lightning strokes are similar to subsequent strokes in natural lightning, it is likely that x-ray emission is a common property of natural lightning.

We provide notes on the design and construction of an Electric Fish Finder -a portable differential amplifier for detecting the electrostatic fields of gymnotiform knifefishes. The device can be adapted to locate electric fishes in any kind of aquatic environment. It is rugged, water resistant, and powered by alkaline batteries. This contribution is part of a series of technical papers designed to encourage students of neotropical ichthyology to explore the ecology, systematics, and electric signaling of gymnotiform fishes.Nós fornecemos o esquema e as instruções para a construção de um Detector de Peixes Elétricos -um amplificador portátil de banda larga utilizado para detectar os campos elétricos de peixes gymnotiformes. Este aparelho pode ser adaptado para encontrar peixes elétricos em diversos ambientes aquáticos. É resistente, à prova d'água e energizado por baterias alcalinas. Esta contribuição faz parte de uma série de artigos técnicos que pretende encorajar estudantes de ictiologia neotropical a explorar a ecologia, sistemática e comunicação elétrica de peixes gymnotiformes.

Charles Piazzi Smyth (1819–1900) was appointed to the post of Astronomer Royal for Scotland and Regius Professor of Astronomy at Edinburgh University in 1846. He was respected for his practical work, and his Teneriffe, an Astronomer's Experiment (1858) is also reissued in this series. However, this book, first published in 1864, is testimony to the author's interest in 'pyramidology', and although it was so popular in his own lifetime that it was reprinted five times, his eccentric interpretation of the data he had collected by measuring all aspects of the Great Pyramid of Giza damaged his scientific reputation. Smyth was convinced that the British measurement standard of an inch as a basic unit of length was associated with the sacred cubit of the Bible. This measure was supposedly incorporated in the Pyramid, which he claimed was built under divine guidance by the Ancient Israelites, and enshrined scientific information.

The author remarked, that the various observers who had seen the eclipse of 1842, gave such generally similar testimony of the place and the size of the red prominences as satisfactorily established them to be some celestial phenomenon. Then as to the question, whether they belong to the sun or the moon, the observers themselves were unanimous in the former view, and the red points then became flaming masses of fire some 40,000 miles in height.

These Notices were chiefly derived from the ordinary correspondence of the Royal Observatory of Edinburgh, from the important character of some of which Professor P. Smyth hoped that extracts from the best of the letters might be of interest to the Society.He alluded first to the astronomers of the United States, a large and increasing body, of no mean order of excellence already, and of the richest promise. Professor Loomis' recent work, which was exhibited, gives sufficient facts to prove the above statements.

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