It is accepted that the spirit level (niveau à bulle d'air) was invented by Melchisedech Thevenot (1620 - 1692) some time before February 2, 1661. However, some people interpret a 1558 text, referring to an insect, as mentioning a spirit level more than one hundred years before it was created by Thevenot...

A 1558 French text describing a spirit level more than 100 years before it was invented?!

enter image description here

Histoire entière des poissons, Guillaume Rondelet, 1558

enter image description here Plumb bob level [fil à plomb, plomb, niveau à]

Do you, as a native French speaker, consider that the text talks about a spirit level or does the paragraph refer to a plumb bob level, a tool invented in antiquity?

  • 1
    It says the insect has the shape of a T or a level ("niveau"), with three feet on each side (or three feet overall). Does not look like a Spirit Level ("Niveau à bulle" in french). There is no mention of a bubble ("bulle") anywhere. – Simon Mourier Feb 2 '16 at 11:04
  • Parce que je ne suis pas sûr que ce soit la réponse, ça se discute justement. – Simon Mourier Feb 2 '16 at 14:35

The text describes the freshwater insect that is called by the author "niveau d'eau douce" and is drawn just below the title. Looking like a hammer shark, its T shape evokes a "niveau". It also has three legs on each side.

In this text, the only reference to an inclinometer is the word "niveau". It is used to give a name to the insect because their shapes are similar.

As indicated by @SimonMourier, there is no indication of the level technology (spirit or plumb bob level).

 The insect is a dragonfly larvae (larve de libellule)

  • It became clear that the 1558 text refers to a T shape level which was called "hammer fish" in Italy, that time. This is a plumb bob level. A spirit level is not like a T and has no common features with the insect described in the book. – Energizer777 Feb 3 '16 at 8:51

Your Answer

 

By clicking "Post Your Answer", you acknowledge that you have read our updated terms of service, privacy policy and cookie policy, and that your continued use of the website is subject to these policies.

Not the answer you're looking for? Browse other questions tagged or ask your own question.