86 



REMARKS. 



Nos. 1, 2, 3, 4, 5, on standing deposited a small amount of sediment, and did 

 not show any unpleasant odour. 



Nos. 6, 7, 8, on standing deposited a considerable amount of sediment. No 

 unpleasant odour except No. 8 which smelt slightly of parafQn oil. 



No. 9— taken not far from sewer outfall— deposited a large quantity of 

 sediment, and had a very putrid odour. 



The tide began to flow about 1-30, consequently Nos. 7, 8, 9 samples are of 

 water backed up by the incoming tide. 



The figures show that the river water is well aerated and' not much polluted at 

 low water, from Derwent outflow upwards. As the tide rises, however, 

 the grossly polluted water from the lower reaches, from Scotswood down- 

 wards will be backed up and cause pollution up past Blaydon. 



B. — August 5th, 1913. 



NOTES. 



Nos. 1 and 2 contain a very deficient quantity of oxygen. 



Nos. 3 and 4. — In these places the oxygen has been removed by organic and 

 other matter. 



No. 4.— Very putrid and contains sulphuretted hydrogen. 



This proves that 30 or 40 °/o of the river water is suflficient to make the whole 



mass putrid, assuming that the sea water is fairly pure which we know 



it to be. 



