# Pressure, friction and deafness.

Today’s post is for Jai at From the Hands Of Quacks for two reasons. Firstly she is writing a piece on history of science blogging for the History of Science Newsletter and in order to collect material she is conducting a survey at her blog for authors and readers of history of science blogs. So please pop over and devote two minutes of your time to filling out her questionnaire. While you’re there you could also take the time to read her excellent blog if you don’t already do so.

I was intending to write this post for Jai before I discovered her survey because today’s obscure scientist relates rather nicely to the main theme of Jai’s blog. From the Hands of Quacks is principally concerned with the history of aural surgery in the 19th century. Today’s birthday boy the French instrument maker, inventor and physicist Guillaume Amontons (August 31st 1663 – October 11th 1705) was deaf.

Amontons made a number of small but significant contributions to the history of science and is exactly the type of minor figure without whom scientific progress would not be possible but who in the popular presentation of the history of science are engulfed in the shadows cast by the so called giants.

As an inventor and instrument maker he produced improved versions of the barometer, the hygrometer and the thermometer. The last is particularly important as he invented an air thermometer that measured temperature using a gas instead of a fluid but did so by registering the change in pressure. This led to him making significant contributions to the development of the gas laws and in particular to directing research along the path towards the discovery of absolute zero.

Amontons other major contribution was the discovery and publication of the laws of friction; his three laws are:

1. The force of friction is directly proportional to the applied load. (Amontons 1st Law)

2. The force of friction is independent of the apparent area of contact. (Amontons 2nd Law)

3. Kinetic friction is independent of the sliding velocity. (Coulomb’s Law)

For a man who many people would, incorrectly, regard as handicapped Amontons managed to contribute much more to the evolution of science than many so-called able bodied scientists.

### 2 responses to “Pressure, friction and deafness.”

1. You are so sweet–thank you for this!

On the topic of French instrument makers, my mentor, David Pantalony (IHPST alumnus, currently curator of the Canada Science and Technology Museum) told me once about the close relationship between instrument makers (especially those that were making instruments for experimental physics and general science) and acoustic instrument makers–their knowledge of sound, wood, and windpipes often enhanced the precision of physics instruments. There was a strong community of these acoustic/scientific instrument makers in France in the 19th century, a cool idea, when you consider how ideas in one discipline can readily influence another!

David just published his book on this, “Altered Sensations,” a review which can be read here:

http://spontaneousgenerations.library.utoronto.ca/index.php/SpontaneousGenerations/article/view/14194

2. A few more notes on friction…

Amontons’ laws concern static and sliding friction; for fluid friction, different laws apply.

Amontons’ first two laws were known to da Vinci, but since they remained unpublished until way later, his discoveries had no impact on the history of tribology (the study of friction).

I was surprised a few years ago to learn how recent is the detailed understanding of static and sliding friction at the molecular level (see, e.g., Ringlein and Robbins, “Understanding and illustrating the atomic origins of friction”, Am. J. Phys. 72(7), July 2004, which mentions progress in “the last 15 years”.)