a network of threads .25 inch apart.
Pfeffer, _Pflanzenphysiologie_, ed. 1, 1. p. 142, recommends the method
and gives Hales as his authority.

{126a} _Pflanzenphysiologie_, 1865 (Fr. Trans. 1868), p. 254.

{126b} He gives it as 15.8 square inches, the only instance I have come
across of his use of decimals.

{126c} Arbeiten, II. p. 182.

{126d} See Sachs' _Pflanzenphys_. 1865 (Fr. Trans. 1868), p. 257, where
the above correction is applied to Hales' work.

{127a} _Vegetable Staticks_, p. 5.

{127b} _Ibid._, p. 14.

{128a} _Vegetable Staticks_, p. 41.

{128b} Janse in _Pringsheim's Jahrb_. XVIII. p. 38. The later
literature is given by Dixon in _Progressus Rei Bot._ III., 1909, p. 58.

{129a} Compare F. von Hohnel, _Bot. Zeitung_, 1879, p. 318.

{129b} This is also shown by experiment xc, _Vegetable Staticks_, p.
123.

{130a} The method by which Hales proposed to record the depth of the sea
is a variant of this apparatus.

{130b} _Vegetable Staticks_, p. 92.

{130c} According to Sachs (_Geschichte_, p. 509) Ray employed this
method.

{130d} Other facts showed that the "gapped" branches did not behave
quite normally.

{131a} He refers (p. 141) to what is in principle the same experiment
(see Fig. 27) as due to Mr. Brotherton, and published in the _Abridgement
of the Phil. Trans._ II. p. 708.

{131b} He notices that the swelling of the bark is connected with the
presence of buds. The only ring of bark which had no bud showed no
swelling.

{133} It appears that Mayow made similar experiments. _Dict. Nat.
Biog._ s.v. Mayow.

{134a} _History of Chemistry_, 1909, I. p. 69.

{134b} Hales made use of a rough pneumatic trough, the invention of
which is usually ascribed to Priestley (Thorpe's _History of Chemistry_,
I. p. 79)

{135a} He speaks here merely of the apples used in a certain experiment,
but it is clear that he applies the conclusion to other plants.

{135b} _Vegetable Staticks_, p. 313. It should be noted that Hales
speaks of organic as well as inorganic substances.

{137a} The above account of Hales' connexion with the Royal Gardens at
Kew is from the _Kew Bulletin_, 1891, p. 289.

{137b} I am indebted to Sir E. Thorpe for a definition of _statical_
"Statical (Med.) noting the physical phenomena presented by organised
bodies in contradiction to the organic or vital." (Worcester's
_Dictionary_. 1889.)

{138a} _Arbeiten_, I.

{138b} Borelli, _De Motu