The plates of daily lives reveal the habits and customs of the population of Sobral and the weather conditions at the time of the eclipse.

Photographic plates were also used to photograph the day to day population. People, monuments, events, nature. In short, everything was recorded in this device, which was used for more than a century to keep the important moments in the history of societies.


Seven plates made at the eclipse maximum point are presented. The observations were carried out with the Mailhat constructor astrographic refractor telescope, with 15cm of objective aperture and 8m of focal length, conjugated with a celostate (set of flat mirrors that allow to register the reflected image of the Sun on a photographic plate). These plates are 23.5cm x 18cm in size.

The images on the plates were obtained when the disk of the Moon totally covered the disk of the Sun, which started at 8:55 p.m., local time, on May 29, 1919. During 5 Minutes and 13 seconds it was possible to record the phenomenon.

At the bottom of the plates you can see a scale of gray tones, called Sensitometry, used to determine the characteristic curve of the photographic emulsion. The curve provides the sensitivity, contrast, fog and saturation region.


In periods of great activity, the sun emits enormous plasma arcs (ionized gas) that are released hundreds of thousands of kilometers in the solar corona. In Sobral's eclipse, the size of this arc was approximately 516,000 kilometers, reaching a height of 142,700 kilometers. The two images show the details of this phenomenon.


In addition to participating in the support and organization of the observations of the eclipse, the Brazilian team made observations of the solar corona using a spectrograph, equipment that records the various "colors" (frequency) that make up the light emitted by the source (in this case, the sun).

The spectrograph is a device that performs the photographic recording of a light spectrum. It was used by the Brazilian expedition to observe and analyze the mechanism responsible for the high heating of the solar corona. The "bands" in the photographic plates represent the observation of the region of the solar corona.


Image of the teams that observed the total eclipse of the sun on May 29, 1919, in Sobral (CE).

From left to right:
Brazilian team: Luiz Rodrigues (1°), Theophilo Lee (2°), Henrique Morize (4°), Allyrio de Mattos (7°), Domingos Costa (9°), Lélio Gama (10°), Antônio C. Lima (11º) and Primo Flores (12º).
English team: Charles Davidson (5°) and Andrew Crommelin (6°).
American team: Daniel Wise (3°) and Andrew Thomson (8°).