76 THE ‘‘ BREAKING” OF BARTON FISHPOND 
A drop of tincture of Iodine turns this solution of chlorophyll 
(I have no doubt that it is a solution of chlorophyll) the same colour 
as seen by reflected light. 
The late Sir Thomas Wardle gave a very interesting account of 
the colouring powers of this little plant in his paper before the North 
Staffordshire Field Club. [| He contends that the chlorophyll occurs 
in this Alga in a liquid state and that it escapes as the plant decays 
thus forming the solution of chlorophyll, I believe the dichroic state 
of the solution of chlorophyll was first noticed by Sir Thomas Wardle, 
he says that in about a month the solution finally assumed an autumnal 
brown tint and compares the changes, to the changes in foliage 
during a year. I was extremely pleased to find on reading Sir 
Thomas’ paper after making my own observations on Barton pond 
that they agreed so closely with the opinions of such an eminent 
authority on the chemistry and physiology of colours and dyes. 
I paid several visits to the pond during 1909 after July 4th. 
On July 31st it was still in the same condition. August 9th, the Alga 
appeared to be slightly dying off ; at the South end it was a bluish 
green colour, rather the shade of corroded copper, the temperature 
of the water was 72 °F.; the smell was very bad from the partly 
decayed Alga. September 11th, there was still a quantity of the Alga at 
the S.W. corner and of the corroded copper colour, most of the pond 
was clearer; the temperature was lower, the water being only 56 oF. 
On October 31st I found the pond quite clear and free from 
Alga except a small quantity adhering to the stems of the dead rushes 
ete. at the South end. During 1910 I made several inspections of the 
pond. June 23rd, I noticed the water had a lot of minute Alge 
floating in it, this proved to be Anabzena Hassallii in considerable 
quantity, and only the slightest traces of Aphanizomenon. 
July 2lst the water was full of bundles of Aphanizomenon 
floating about, making it look a sea-green colour, but was not in 
sufficient quantity to forma scum on any part of the pond. The 
water itself was quite clean and colourless. On making a microscopical 
examination of samples taken on this day, I found the gliding 
movement mentioned above in almost every field examined } had 
never seen it so frequent or distinct before. 
+ Transactions North Staffordshire Field Club, Vol. XXXI p 121, 
