22 
Record.i of the Geological Surrey of India. 
[voi,. III. 
to the eastward, where they creep round along the Gulf of Martaban, and blend with the 
deposits of the Sittang valley. Proportioned thus regularly as the Irawadi delta is, as 
regards contour, with its three sides respectively 129, 137, and 176 miles long, it may not 
at once seem obvious how Mr. W. Blanfbrd, in speaking of it, called it “ a less perfect delta’’ 
than that of the Ganges, I shall, however, endeavour to show wherein it differs essentially 
from such delta of the Ganges, not in form, hut in respect to its composition and history. 
The most striking feature connected with it, is not its mere flatness, which is naturally 
to he looked for in such an area, hut its extremely low level. No definite assertion can of 
course be made, but I think I am well within the mark when I say that 2,000 square miles 
of this tract must be below the level of a high spring tide and fully as much more not 
raised more than a foot or so higher. Passing through any of the creeks when a spring 
tide is at its height, the water is seen pouring inland up every channel and watercourse, and 
diffusing itself over both fields and uncultivated ground, and the conviction produced is, that 
a permanent submergence of a considerable tract within the delta would be the result of the 
water beiuf maintained at the full height of the springs for any considerable period ; as it 
is, however, in the course of an hour or so, the tide falls and the flooded land relieves itself 
through the usual channels. This extremely flat character of the country may be surmised 
from a mere inspection of the map, from the numerous lakes or “ Engs” as they are called, 
scattered all over lower Pegu, and from the anastomosing and often tortuous character of 
even the largest river channels. 
For instance, a little below the important town of Nyoung-don the Irawadi divides into 
two nearly equal branches, each possessing the dimensions of a first class river, one branch 
flowing south and discharging itself by the Oalla mouth, whilst the more westerly branch 
enters the sea by the Irawadi mouth. Twenty-five miles as the crow flies below the point 
of bifurcation of the two streams, is the small village of Tan-ta-lop Kyoung, to which I shall 
hereafter refer, but following the bank of the former branch or Dalla river on which it is 
situated, the distance is raised to 45 miles or nearly double. From the same point of bifurca¬ 
tion, at the same distance as the crow flies of 25 miles, on the other branch or Irawadi river 
is the important town of Shuay-loung; the distance to which, following the river bank, is 
42 miles nearly. 
Still more tortuous is the Daga river in some parts, which constitutes the most westerly 
channel of the Irawadi within the delta, and which, though a far narrower river than either 
of those above mentioned, maintains a deep and permanent channel. From the village of 
Shekhabyeng to the point of discharge of the Daga lake, is, as the crow flies, 18 miles, but 
measured along the river bank the distance actually exceeds 55 miles, which will give a 
notion of the extremely level character of the country it traverses—which character is not 
confined to the delta merely, but marks more or less all lower Pegu, save in the vicinity of 
the hills. 
Such beinw the surface, character, and conditions of the delta we might not unreasonably 
be led to expect within it a great development of the newer or Irawadi alluvium, but so far 
from this being the case, the country is almost entirely composed of the older group to the 
almost total supersession of the newer. This will be most forcibly realised from the state¬ 
ment that the entire area (excluding the actual river channel) occupied by the newer or 
Irawadi alluvium in the valley, amounts to but 200 square miles, of which 60 miles is made 
up of scattered patches adjoining the river, all lying above the bifurcation of the Dalla and 
(Pantauau) Irawadi rivers, whilst the remaining 140 square miles constitute an isolated tract 
or oasis of recent deposits, below Pantanau, which seem to occupy an original trough or 
depression in the surface of the older group. From this it will be apparent, that with great 
similarity of surface conditions between the deltas of the Ganges and Irawadi, great dissimi¬ 
larity exists touching their geological constitution, the newer group of alluvial deposits so 
largely developed in the former being, so to speak, absent in the latter. The cause of this, 
briefly stated, is the fact that the delta of the Irawadi at this present time is in precisely the 
condition of the delta of the Ganges at, the time when the first layers of Gangetic alluvium, 
70 feet below the present surface at Calcutta, were being deposited, and when through the 
single or joint action of deposition and elevation, the older marine group had become suffi¬ 
ciently raised to admit the deposition of beds stamped with a fluviatile and terrestrial character, 
and even the accumulation of such matters as peat, to permit of which the newly raised land 
must have been at least as high above the sea, as the better raised portions of the Irawadi 
