Slide Rules

Cylindrical slide-rule made by Keuffel & Esser about in 1885, on patent by Edwin Thatcher in 1881

Loose pebbles were the first objects used to aid humans in calculating numbers. Later they were used as counters on ruled boards before a range of materials were used to suspend counters on wire frames. This fixed wire structure known as the 'abacus' was developed in India and later adopted in China and Europe.

Sydney Observatory and the Carte Du Ciel or Mapping the Stars Project

In Autumn 1886, George Gabriel Stokes, President of the Royal Society of London received a letter from Admiral Mouchez, the Director of the Paris Observatory, "… in response to the presentation of specimens of the admirable star photographs by the MM. Henry, several astronomers to whom they had been sent suggested that it would be well that a conference of astronomers of various nations should be held, with a view to taking concerted action for obtaining on a uniform plan a complete map of the whole starry heavens."

The 1879 Sydney International Exhibition

Interior of the Garden Palace, New South Wales Court, Sydney, 1879, Powerhouse Museum Collection

The Sydney International Exhibition opened the doors of its main building the 'Garden Palace' on 17 September 1879 and closed them seven months later. Many figures in colonial Sydney talked of the success of the huge project and the Commissioners of the Sydney International Exhibition certainly felt it had "undoubtedly emphasized a new era in the history of the Colony, and projected the value of Australia on the minds of the inhabitants of those older countries". But the 1,045,898 visitors that passed through its gates were perhaps the most eloquent testimony to its triumph.

Sydney Observatory Star Camera, Moon and Jupiter Photographs 1891

Photograph of the moon, taken by Russell and Short Sydney Observatory, about 1891, original negative held by Powerhouse Museum

Sometime around July 1891 Sydney Observatory received a new enlarging lens for the star camera. This attachment, when combined with the Grubb lens which had arrived in September the previous year, enabled the observatory to take highly magnified images of double stars, the moon and other objects. 

Once fixed to the telescope the camera was able to produce glass plates 6 ½ x 6 ½ inches (16.5 x 16.5 cm) square, which was the size stipulated for the Mapping the Stars project. This gave the instrument a magnifying power of the telescope equal to 179 feet (5455.9 cm). The Dallmeyer lens previously used had produced a result which was the equivalent of taking a direct photograph in a telescope 47 feet (1432.6cm) long. 

Transylvanian blood-suckers

Apothecary jar, for holding medicinal leeches, slip-cast earthenware, made by S. Maw and Son, London, England, 1860-1870 http://www.powerhousemuseum.com/collection/database/?irn=182254#ixzz2lGArzAaV
Under Creative Commons License: Attribution Non-Commercial

Last week I started work on a collection of objects relating the period of the Australian Gold Rushand one of the objects was a porcelain medical jar made by S. Maws and Sons between 1860 and 1870. It had been used for holding leeches and I thought there may be an interesting connection between these blood-sucking animals and the diggers who often spent long hours panning or ‘wet-digging’ in streams and rivers.

The Eureka Flag; 150 year mystery solved?

While working on a story relating to the Eureka Stockade I came upon some interesting information which may clarify a nearly 150 year old mystery relating to who designed the famous Eureka flag. Some accounts credit a Canadian miner, “Captain” Henry Ross, as being the designer of the flag. Others say the designer is still unknown and that Ross was simply the person who took the design to the three women, Anastasia Withers, Anne Duke and Anastasia Hayes, who sewed up the flag in time for the rally on 29 November 1854.

Stalin, Zoo Kid and ruin a movie: tweekly update

Last weekend I attended a Graphics workshop at the Sydney Opera house and was lucky enough to catch the fireworks for the Naval Fleet Review. Our position at the Opera House bar was a great opportunity to get some photos on my phone.

The Tyrant as Editor an article by Holly Case in the Chronicle of Higher Education offers a great reading of the way Stalin used his blue marker pen Stalin used to execute and imprison thousands from his realtive comfort of his desk.

Zoo Kid - Out getting Ribs