own sake; but the difficulty and labour of the undertaking, and the learning and historical research that it involved, had hitherto warned off the men most competent to discharge it. The zeal of Maxwell for his new Cavendish foundation was not thus to be deterred. Already in July, 1874, we find him writing from Glenlair to Mr Garnett (Life, p. 389):
In the MS. he appears to be familiar with the theory of divided currents and also of conductors in series, but some reference to his printed paper [on the Torpedo] is required to throw light on what he says. He made a most extensive series of experiments on the conductivity of saline solutions in tubes, compared with wires of different metals, and it seems as if more marks were wanted for him if he cut out G. S. Ohm long before constant currents were invented. His measures of capacity will give us some work at the Cavendish Laboratory, before we work up to the point where he left it. His only defect is not having Thomson's electrometer. He found out inductive capacity of glass, resin, wax, etc.
According to Mr Garnett (Life, p. 555) who was in a position to be intimately acquainted with the facts:
The amount of labour which Professor Maxwell bestowed on this work during the last five years of his life can only be known to those who were constantly in his company. Nearly all the MSS. he transcribed with his own hand, the greater part being copied after midnight. . . .Every obscure passage or alteration was the subject of a long and searching investigation: and many were the letters written to the Librarian of the Royal Society and to scientific and literary friends in different parts of the country, to gain information respecting the meaning of obsolete words and symbols, or the history of individuals. And besides this, and a comparison of Cavendish's results with those obtained by subsequent investigators, Maxwell repeated many of Cavendish's experiments almost in their original form, only employing modern instruments for the purposes of measurement.
The result of five years of continual application to the subject was the volume published in October, 1879 by the Cambridge University Press, a few weeks before the death of its Editor, and now reprinted in different form. The introductory sketch prepared by Maxwell, probably at the end of his task, gives a clear and most interesting summary of the electrical work of Cavendish: the postscript dated 14 June, 1879, describing some manuscripts on magnetism that had just come to hand, coincides with the beginning of his final illness.
There is perhaps no instance in the history of science in which the unpublished records left by an investigator have been arranged and elucidated with such minute fidelity. Careless though Cavendish was of scientific reputation, intent on pressing on to new solitary achievement, to the neglect of publication, due as it would seem as much to the habit of continual postponement of final preparations for the press as to the fascination of exercising his powers of discovery—and even, as it has
