On August 30, after entering things wanted, he wrote in the Laboratory Book:
‘No experiments are to be made or carried on in the laboratory without the consent and approbation of the Professor of Chemistry. The attempt at original experiment, unless preceded by knowledge, merely interferes with the progress of discovery. There are a sufficient number of new and interesting objects which a modest student would wish to pursue, and in which the path is marked and distinct.’
On September 8 he was again experimenting on the decomposition of nitrogen. He wrote, ‘And if it be said that no air and no water were present (in the potassium, boracic acid, and ammonia), the experiment is decisive as to the destruction of nitrogen and its containing the same kind of elementary matter as water.’
To the like experiment, September 13, he wrote, ‘This experiment seems almost decisive on the decomposition of nitrogen.’
Soon after he wrote, ‘Query, Does not the general tenor of the last experiments lead to the suspicion of the decomposition of nitrogen?’
On September 16 he made this note: ‘Objects to be attempted during the next week: To-morrow, oxymuriatic acid pure, to try absorption by two grains of different metals—tin, arsenic, antimony, bismuth, copper, platina, lead, zinc.’
On October 4, when he was about to start for Dublin, he wrote in the Laboratory Book, ‘The principal thing, the laboratory in complete order.’ He was absent from October 4 to the middle of December. No experiments were entered until October 27; then there are some on oxymuriatic acid by E. Davy.
On November 15 the action of oxymuriatic gas on dried nitrous gas was repeated.
The next experiment was on November 24. ‘Two grains of silver were entirely converted into horn-silver; the absorption of chlorine gas was 9⁄10 of a cubic inch.’ This was the first use of the word CHLORINE in the Note-Book; it occurs daily afterwards. Oxymuriatic gas continued the chief subject of the experiments in the laboratory up to the end of February in the following year.