3 10  Annual  Report  for  1910  of  the  Consulting  Chemist. 
(Soils  dried  at  100°  C.)  (Elliot’s  system)  (Ordinary  system) 
Organic  matter  and  loss  on 
heating 
1046 
9-53 
Oxide  of  iron 
6-78 
7-23 
Alumina 
7-25 
7-07 
Lime  .... 
•23 
17 
Magnesia 
•39 
•30 
Potash .... 
•41 
•36 
Soda  .... 
•23 
•24 
Phosphoric  acid  . 
•43 
•38 
Sulphuric  acid 
•10 
12 
Insoluble  siliceous  matter 
73  72 
74-60 
100-00 
10000 
Nitrogen  .....  347  ’309 
It  will  be  noticed  that  the  soil  “A”  contained  alike  more 
organic  matter  and  nitrogen  than  “ B,”  while  it  also  had  rather 
more  lime,  potash,  and  phosphoric  acid.  So  that,  presuming 
the  soils  to  have  been  originally  alike,  it  would  certainly 
appear  that  an  improvement  had  been  effected  under  the 
system  of  laying-down  grass  advocated  by  Mr.  Elliot. 
2.  Water. 
Green  growth  on  water  in  reservoir. 
A Member  of  the  Society  complained  of  trouble  which 
was  experienced  with  the  water  supply  of  a large  mansion. 
The  water  came  from  a spring  far  away  from  any  pollution, 
and  was  carried  down  to  an  open  concreted  reservoir.  At 
certain  times  of  the  year  the  water  from  the  reservoir  was 
noticed  to  have  a peculiar  taste,  and  also  a regular  growth  was 
found  to  form  on  the  bottom  of  the  reservoir  and  gradually  to 
float  up  to  the  surface.  Some  of  this  floating  matter  was  sent 
me,  and,  through  the  kindness  of  the  authorities  at  Kew 
Gardens  and  of  Professor  Biffen,  the  Botanist  to  the  Society, 
was  identified  as  being  Phormidium  laminosum  Gom. — one 
of  the  blue-green  algfe  ( Cyanophycece ). 
Experiments  were  made  on  using  sulphate  of  copper  in  the 
water  for  the  purpose  of  destroying  the  alga,  and  the  alga 
was  found  to  be  killed  by  the  sulphate  of  copper  when  used 
at  the  rate  of  one  part  to  five  million  parts  of  water. 
The  following  is  a list  of  samples  analysed  on  behalf  of 
Members  of  the  Society  during  the  twelve  months  December 
1,  1909,  to  November  30,  1910  : — 
Linseed  cakes  .........  22 
Undecorticated  cotton  cakes  ......  36 
Decorticated  cotton  cakes  . . . . . . 12 
Compound  feeding  cakes  and  meals  ....  50 
