Ixxvi 



the conservability of seeds, on the ozonic element of the atmosphere, and 

 on the effect of varied proportions of carbonic acid on plants analogous to 

 those of the coal-measures*. These last-mentioned experiments are among 

 the very few which can be referred to as throwing light on the curious 

 question whether the amazing abundance of vegetable life in the carboni- 

 ferous ages of the world may not have been specially favoured by the pre- 

 sence, in the palseozoic atmosphere, of a larger proportion of carbonic acid 

 gas than is found at present. 



A favourite subject of research with Dr. Daubeny, naturally springing 

 from his volcanic explorations, was the chemical history of mineral waters. 

 The presence of iodine and bromine in some of these formed the subject 

 of a paper in the Philosophical Transactions for 1830; and a Report to 

 the British Association in 1836 included a general survey of mineral and 

 thermal waters. This subject was not neglected in his c North-American 

 Tour' (1837—38), which contains a great number of interesting observations 

 on the character of the country which he traversed, as well as the educa- 

 tional institutions, where he was heartily welcomed. 



Dr. Daubeny was a great traveller, almost an annual visitor to the con- 

 tinent, usually, at least in his later years, accompanied by some scientific 

 or literary friend, some member of his family, or some young Oxonian of 

 cultivated taste, to whom the sight of Auvergne and the Tyrol in the com- 

 pany of such a guide was a gift of priceless value. 



In one of his journeys to Spain in 1843, for the purpose of studying 

 the geological relations and agricultural value of the great phosphatic de- 

 posit of Estremadura, he was accompanied by Captain Widdringtoa, R.N. 

 It was a journey prompted by benevolence and attended by hardship. No 

 doubt, in some future day, railways will carry heavy loads of this valuable 

 substance to enrich the agriculture of Spain f. In another year he might 

 be found in Norway, or musing in the Garden at Geneva, where he was 

 alwavs welcomed by the great botanist whose friendship he gained in early 

 life, and to whose memory he has devoted a careful critical essay, which 

 was read to the Ashmolean Society in 1842 J. 



It was at Geneva that he " began to estimate at their true w r eight the 

 pretensions of Botany to be regarded as a science, and to comprehend the 

 principle on which it might be inculcated as constituting an essential 

 part of a liberal education." Here he first pursued his botanical studies 

 under the guidance of Decandolle in 1830, and thus qualified himself 

 for the Professorship to which, as already observed, he was appointed in 

 1834. 



Chemistry, however, was the thread which bound together all the 

 researches of Dr. Daubeny ; not that he was personally a dexterous 

 * Miscellaneous Memoirs and Essays, 1867. British Association Reports, 1837-57. 

 t Memoir read to the Geological Society in 1844. 



\ Daubeny's Miscellanies, vol. ii. " On the Life and Writings of A. P. Decandolle." 



