1811 in science

The year 1811 in science and technology involved some significant events, listed below.

Astronomy

Johann Karl Wilhelm Illiger publishes Prodromus systematis mammalium et avium, an updating of Linnean taxonomy and a major influence on the concept of the 'Family' in biology. He first defines the infraclass Marsupialia.
Peter Simon Pallas begins publication of Zoographia rosso-Asiatica, sistens omnium animalium in extenso Imperio rossico, et adjacentibus maribus observatorum recensionem, domicilia, mores et descriptiones, anatomen atque icones plurimorum in Saint Petersburg.

Bernard Courtois discovers iodine.
Joseph Louis Gay-Lussac and Louis Jacques Thénard publish Recherches Physico-Chimiques, faites sur la pile; sur la préparation chimique et les propriétés du potassium et du sodium; sur la décomposition de l'acide boracique; sur les acides fluorique, muriatique et muriatique oxigéné; sur l'action chimique de la lumière; sur l'analyse végétale et animale, etc. in Paris.
Amedeo Avogadro proposes Avogadro's law, that equal volumes of gases under constant temperature and pressure contain equal number of molecules.

Charles Bell publishes An Idea of a New Anatomy of the Brain, starting to distinguish between sensory and motor nerves.
Abraham Colles publishes A Treatise on Surgical Anatomy in Dublin.
Francis Place publishes Illustrations and Proofs of the Principles of Population, including an examination of the proposed remedies of Mr. Malthus, and a reply to the objections of Mr. Godwin and others in London, the first significant text in English to advocate contraception.

Amedeo Avogadro proposes his hypothesis relating volumes and numbers of molecules of gases.

Friedrich Koenig, with the assistance of Andreas Friedrich Bauer, produces the first steam rotary printing press, in London.