Ascent and Dencent of Water in Tree><. 



\V 



strontr scaffolding and special apparatus for rapidly cuttino^ the base 

 of the tree and avoidinfr its exposure to air. Accordinsrly a simple 

 ]ireliniinary experiment was tried upun a small tree of Acacia 

 iiioUisxima- irrowing- in the Herbarium <rrounds. The tree was four 

 years old, 25 feet high, and had a circumference, l^ feet above 

 ground, of 26 inches. Tlie spread of the tree was 14 feet, and the head 

 was nearly cylindrical up tn 6 feet from the top, the lowest branch 

 being 5 feet from the ground. The l)ase of the tree was surrounded 

 by a cup made of canvas, and cemented until watertight. The cup 

 had a capacity of 15 litres when filled u^d to a uuu'k below the brim. 

 In March, after filling the cup Avith water, a ring of bark and wood 

 was cut away under the water near the base of the cup, by means of a 

 sharp chisel, to a depth of 1^ inches all round the tree. The remain- 

 ing core of wood was quite strong enough to support the entire tree, 

 liut was apparently inactive in the ascent of sap. (See PI. V[I.). Sufti- 

 cient copper sulphate was then added to make a 5 per cent, solution, and 

 after some 26 litres ha'l been absorbed, which meant the addition of a 

 large amount of water, the copper sulphate remaining was washed out 

 and replaced by a solution of eosin. As can be seen from the data 

 given beneath, tho au;ount of water absorljed was considerable, but 

 rapidly fell off after the first few hours. 



10 



11.30 



12.30 



1.3U 



2. 30 



3.30 



4.30 



10.30 



Time. 

 Wednesday, 13lli 

 a. 111. - 11.30 a.iu. 

 a.m. - 12.30 p.iu 



.\iiiount absorbed. 



p. Ill 

 p. Ill 



() litres. 

 7 litres. 

 1.30 p.m. - H\ litres. 

 2.30 p.m. - 5 litres. 



Copper sulphate replaced by eosiu. 

 p.m. - 3.30 p.m. - t.j litres, 

 p.m. - i.30 jj.iii' - 22 litres, 

 p.m.- 10.30 p.m. - i> litres, (li litres per hour) 

 p.m.- 9.30a.m. - 11 litres. (1 litre per huiir) 



Thursday, 14th 



!t.30 a.m. - 10.30 a.m. Fresh surfaces ut wood cut 

 10.30 a.m. - 11.30 a.m. - 2 litres. 

 11.30 a.m. - 12.30 p.m. - l\ litres. 

 12.30 p.m. - 1.30 p.m. - 2i litres. 



1.30 p.m. - 2.30 p.m. 

 2.30 p.m. - 3.30 p.m. 

 3.30 p.m. - 4.30 p.m. 

 4.30 p.m. - 10.30 p.m. 

 10.30 p.m. - 10.30 a.m. 



l.j litres. 



Ij litres. 



1 litre. 



5 litres (0.83 par hour) 



5 litres (0.83 per hour) 



Friday, loth. 



10.30 am. - 11.30 a.m. - ^ litre. 

 11.30 a.m. - 12.30 p.m. - 1 litre. 



- Briii'lit suu 



Overcast, clearing 

 .slightly to mill-day 



Cloudy 



Siuii and slight clouds 



Cloudy 



Slight sun 



Bright 3Un 



