ee - : s - 
Proceedings of the British Association. ie 55 «; 
crystals: while the mother liquid is Foktrea and yields a large 
quantity of parabanic acid, or oxa urate of ammonia. By this. 
process the author obtains from 100 | parts of uric acid, 65 of an- 
hydrous alloxan, or 90 of alloxan +6 aq. From alloxan, allox- 
antine is easily obtained by the action of sulphuretted hydrogen. 
Thionurate of ammonia is easily formed, by boiling a solution of 
alloxan with sulphite of ammonia, and free ammonia. Uramile 
is also easily obtained, by iling a solution of thionurate of am- 
monia, with an excess iilute.sulph acid. Murexide is ob- 
tained, as has been already described, (p. 46 of ‘this No.) The 
theory of the formation of murexide is of great importance in ref- 
erence to organic coloring matters.» 
a 
Sect. C. Geology and Physical Geography. 
Dr. Robb presented a communication on the geology of the 
country around the River St. John, in New Brunswick. The 
St. John is as large as any river of the first class in Europe. It 
drains a large portion of the province of New Brunswick, and 
the volume of water which it discharges into the Bay of Fundy 
is very great, especially during the spring floods. Yet in one 
place the river is so contracted that it is not more than 310 feet. 
in width. In the Bay of Fundy, as is well known, the tides rise 
higher than in almost any other part of the globe, there being» 
sometimes, in spring tides, arise of from 40 to 60 feet. The 
tidal wave is then forced up into the narrow. parts of the river, 
“ti causes a backward fall of water, against the natural current, 
of many feet in height. Dr. R. allnded to the singular configu- 
ration of the country in the vicinity of the river, it being shaped 
in terraces, one below the other. The river, from the distance, 
between the first or uppermost pair of terraces, appears to have 
been of much greater width, and subsequently to have grad- 
ually become contracted, until confined within its present narrow 
limits. The higher terraces slope towards the stream, the lower 
ones become more horizontal, and the lowest is with a slope 
turned from the river; an ‘appearance which Dr. R. explained 
by the successive depositions of alluvial matter near the bed of 
the stream, and extending no farther, so that depressions resulted 
behind these depositions, which often contain water. In no 
part of the world can the phenomena of rivers be studied better 
than in America, from the little alteration produced upon them 
