Recueil de mémoires, rapports et documents relatifs à l'observation du passage de Vénus sur le Soleil.

Scarce first edition of one of the first publications on astronomical photography. A fine, fresh example of extensive observations made for the 1874 transit of Venus over the Sun.

The passage of Venus between the sun and the Earth is the rarest predictable astronomical phenomenon, and it occurs twice every 113 years with an eight-year interval between the two instances. From its first predicted incidence in 1631 through to its most recent in 2012, this particular kind of solar eclipse has been historically a crucial means by which to measure the universe. More specifically, in the XVIII and XIX centuries, the phenomenon was closely monitored in order to determine as accurately as possible the size of the solar system through the measurement of the solar parallax and the distance between the Earth and the sun.

The solar eclipse of 1874, detailed in these seven volumes, was only visible from the Pacific and Oceans. Several national observation teams were sent from Europe and North America to study the phenomenon in situ, making of the event a truly exploratory expedition across the globe.

The present work collects the documented efforts of the French scientific team, a group of fifty scientists who set up observational stations at Peking, Saigon, Yokohama, Nagasaki and Kobe in the northern hemisphere, and on the Isles of St. Paul and Campbell, as well as in Noumea, in the southern hemisphere.

Besides the astronomical observations detailed below, the reports also include research on the climate, zoology, botany and geology of several remote territories. These are particularly detailed in the cases of the Isle of St. Paul, the southern Indian ocean, Reunion Island, and the Isle of Campbell, to which two whole volumes (one of text and one of plates) are dedicated.

As well as describing epic journeys through unchartered territories, the work also testifies to a crucial transition in the advancement of astronomical studies it records the very first instance of photographic techniques used as astronomical research tools. Previously, in 1769, unsuccessful attempts were made at measuring the parallax with the aid of traditional telescopic lenses during the transit of Venus. With the subsequent transit of 1874, a particular form of photography called 'photogenic revolver' was introduced to by the French team to remedy the deficiencies of previous methods. This remarkable transition was spearheaded by the astronomer Jules Janssen, a prominent member of the Academie des Sciences, chairman of the observatory in Meudon and once considered equal to Pasteur for his contribution to the advancement of science. Photography provided a groundbreaking solution to the previously unsurmountable issue of accuracy. Astronomers could finally gauge the 'reality of things,' unmediated by the subjective element of the human eye. The decision to adopt the 'photogenic revolver' is beautifully documented in the present volume by numerous photographs of astronomical phenomena taken during Janssen's expedition. The entire last volume is dedicated to the results of photographic observations. A 79-pp. Annexe was published 5 years later, in 1890, and is often not included in the sets we could trace, as here.

The adoption of the 'photogenic revolver' had a long-term groundbreaking effect on the development of new scientific methods of recording, and it pioneered the legitimisation of the medium of photography in the arts and sciences alike. One of the contributors to the present research was Pierre-Henri Puiseux, who published 20 years later the celebrated and monumental Atlas photographique de la Lune.