How much research is enough?

We at Tesseract pride ourselves on finding arcane objets of science and medicine, and on researching them thoroughly. But we feel our research is always incomplete; rarely can we even answer of the journalist's six basic questions: "WHO, WHAT, WHEN, WHERE, WHY, and HOW".

Here we present two examples, and would welcome further insight. We have in stock a monocular of truly exceptional quality, certainly 18th century, and probably English, based on the casework with its scalloped silver trim, etc. But WHO made it and WHERE? Perhaps the leather stampings can be identified, or the style of engraving on the mother-of-pearl. Many analyses could be done, from the origin and species of the rayskin, to impurity content of the silver, to microarcheological studies of pollen grains, etc., caught as dust in little crevices. Where does / should / must one stop?

Secondly we have a fascinating level, described as follows:
SIXTEENTH CENTURY LEVEL, PROBABLY FOR GUNNERY, Continental, signed “A. Pourtales, 1588.” The level is of sturdy brass, 7-5/8” (19.5 cm) wide from foot to foot, and over 1/4” (7 mm) thick. An integral 90° arc is divided every degree 0° ± 45° and labeled every 5°. There are distinctive early numeral shapes, in particular the z-shaped “2” and the slanted topless “5.” The vertex is pierced for use with string and plumb bob. The arms are decorated with sinuous floral designs, engraved and punched. Surfaces have linear outlines throughout, and there seem to be small traces of gilding. The reverse is otherwise plain but for a preliminary scale division on the arc. Condition is good, the brass with a fine dark patina, noting nicks and a stress crack in the arc.
This is a splendid example of early level, probably made for setting elevation (or depression) of a cannon . Bion (1709) shows a similar level on the breech of a cannon, and various forms of gunner's level are illustrated by Bennett & Johnston (The Geometry of War, 1500 - 1750).
The year 1588 is significant, signalling the defeat of the Spanish Armada (with its invasion fleet of 130 ships!) by the British. It is difficult to pin down the maker; the name “Pourtales” itself is widespread. In one name search, for example, we find a Count Albert Pourtales exploring the Wild West in the early 19th century. He was born in Paris, but a descendent of Huguenot refugees who had emigrated to Neufchatel (Prussia, now Switzerland) in 1720. His father served in the Prussian army, then for Napoleon, and finally for the Berlin court. The numeral shapes are another small clue to origin, the “2” form suggestive of a German origin. But more research needs to be done.

So we know WHEN and by WHOM it was crafted, but WHERE was it made, and for WHAT exact purpose? And how do we even approach these questions? Such mysteries, in fact, are the real fascination of our business.