Determining the right time, or the establishment of a culture of astronomical precision at Neuchâtel Observatory in the mid-19th century

In the mid-19th century, the need for an accurate time becomes ever more important for many economic and industrial sectors, as well as for maritime and railway transport. States took a keen interest in these developments, which resulted in the founding of an increasing number of state observatories. While this well-known phenomenon has attracted the attention of numerous historical researches, the actual setting up of an observatory has more rarely been studied. Based on the well-documented case of the Observatoire cantonal de Neuchâtel, we will look at the setting up of the establishment through its scientific instruments and work procedure. Founded in 1858, the Observatory was primarily intended to fulfill the needs of the watchmaking industry while contributing to the progressive standardization of Swiss time. Adolphe Hirsch, the Observatory’s first director, spent 3 years setting up, installing, and calibrating an operating chain dedicated to the time service. The astronomer’s correspondence shows his expectations and the manufacturers’ technical capabilities. We can thus reconstruct the steps in the design of the scientific instruments—which operated as a network. The outcome being a high-performance operating chain for the time determination. During the commissioning process, Adolphe Hirsch chose an emerging technology—the printing chronograph. In fact, the Observatory was entirely configured around this new method, placing this institution among the first in the field. This new observation technique modifies the episteme of time determination and the role of the human factor within the process.