This is an astrolabe created by Jamal-al-Din ibn Muqib in 1666 in Lahore.
First of all, it is an instrument for navigation with Arabic origins as seen before. More precisely, it is an astronomical instrument for observation and analog calculations. It has multiple functions : it makes it possible to measure the height of star, including the sun, and thus to determine the time of observation and the direction of the celestial body. Its design, whose Greek origins date back to antiquity, much later perfected by the Arabs, is based on a flat projection of the celestial vault and the local sphere, called stereographic projection.

This is the William Thomson’s tide predictor that he did in 1872.
This machine is a mechanical analogue computer which traces the tidal curve for a given location, by combining ten astronomical components. It is the first working machine of Thomson’s design, based on his application of harmonic analysis to tidal phenomena. More precisely, William Thomson’s tide predictor was constructed by the London firm of « A Légé and Co » which made a wide variety of scientific instruments for commercial and government clients, including an encryption machine.

This machine is a trial assembly of a general-purpose computing machine that would, if finished, have measured some 20 feets long and 15 feets high.
Charles Babbage started to work on the design of the Analytical Engine in 1834 following the collapse of the project to build the Difference Engine. His idea evolved rapidly, and, in 1838, most of in the important concepts used his later designs were established.