298 
DR. HASSALL ON THE FREQUENT PRESENCE 
observed after four or five days’ exposure gradually to change colour; the pellicle or 
scum which had formed on the surface of the urine became at first slate-coloured, 
and at length deep blue, with here and there a rusty-red tint : the urine also under- 
went, at the same time, some remarkable changes, becoming thick and turbid, 
deep brown, greenish, bluish-green, and finally of a faded yellowish-green colour; a 
considerable sediment was found at the bottom of the glass, this was deep brown, 
soft and deliquescent, intermixed with a little blue colouring matter, and it had a 
medicinal smell resembling somewhat that of valerian. 
In this state, without undergoing any further material changes, the urine remained 
for many days. 
Examined with the microscope, the scum or pellicle on the surface was found 
to consist of Vibriones, innumerable animalcules, and crystals of triple phos- 
phate, with a great many fragments and granules of a deep and bright blue colour. 
So remarkable and striking was the appearance presented by this urine, that I 
could not help fancying a mistake must have occurred, and that possibly some 
foreign colouring matter had accidentally found its way into the urine ; I therefore 
procured a second sample of the same urine, taking every precaution to avoid fallacy, 
and keeping it in a room to which no one had access but myself. Gradually the 
same changes ensued as in the first sample, and this likewise became blue. 
Having thus ascertained that the changes observed were due to something con- 
tained in the urine itself, I next proceeded to set aside in open vessels a series of 
urines, all from the same patient, noticing the alterations which occurred from day 
to day. 
The first urine of the series, when passed, was somewhat alkaline to test-paper, 
had a specific gravity of 1017, and was of a light brown colour; there formed on its 
surface, in the course of three or four days, a thick, greasy-looking, soft scum, con- 
sisting of Vibriones and very many large and fine crystals of triple phosphate ; at 
about this time the scum became greyish-blue, lavender, bright blue, and finally, 
after four or five days more, of a deep indigo-blue colour, which was permanent. 
When disturbed or broken, the blue crust usually turned, after some hours, rusty-red 
at the broken or fissured part, but gradually the original blue colour was restored. 
The urine itself at the same time underwent some singular changes; it became thick, 
brown, green, bluish-green, and finally nearly black. As evaporation took place, the 
blue crust became attached to the sides of the vessel, and on pouring the urine into 
another glass, there was found a considerable quantity of a brown, extractive-like 
substance at the bottom of the vessel, mixed with some of the blue colouring matter 
which had fallen from the surface of the liquid. 
In the second urine of the series the changes were similar in kind, but less in 
degree. This urine was alkaline, of specific gravity 1015, and the pellicle of Vibriones, 
animalcules and triple phosphate which formed on the surface became gradually 
coloured as before, being first slate-coloured, then bluish, and lastly light blue. The 
