I. New experiments on the question of the fixation of free nitrogen. (Preliminary notice.)

In a paper presented to the Royal Society in 1887—1888, and printed in vol. 180 of the ‘Philosophical Transactions,’ we discussed the history and the present position of the question of the sources of the nitrogen of vegetation. We referred to the conclusions arrived at about thirty years ago from the results of Boussiugault and from those obtained at Rothamsted, up to that time. We gave the results of some experiments which had been recently made at Rothamsted in connexion with the subject, and review and the evidence and conclusions of others published within the last few years.