3. Geology and stratigraphy.-The older strata are the same as those of the Lashio field, and nothing more need be said about them. The tertiary strata may be seen best along the banks of the Nampong between Manzè and Namma, and although the result was not very satisfactory as regards the coal-seams, it yielded very valuable observations about the tertiary strata. They consisted chiefly of grey and yellow sandstones, blue shales very finely bedded, like those met with in the Chindwin, and the concretions of hydroxide iron were not wanting. The strata have a general dip to east-north-east for about half the distance between Manzè and Namma, then the dip suddenly changes to the opposite direction. The tertiary strata therefore form an anticlinal fold. This observation is ample proof that the coal-seams found in this part cannot be deposited locally, and if we are justified in drawing conclusions regarding the Lashio coal-field from this condition of stratification, it may be held that the Lashio coal-field also is by nature a throwndown block.

4. Localities of outcrop.-(1) The first outcrop may be seen on the left bank of the Nampong, a little above the village of Manzè. A thin coal-seam of about 4 inches in thickness may be seen here in the water-level; nothing of the surrounding strata is however visible.

(2) The second outcrop is a little below the same village, and here a little more can be seen. The lower stratum is formed by a thickish bedded sandstone of yellow colour on which rests a seam of 3 inches in thickness; then follows clayey shale, about 5 feet thick; then again a coal-seam of 6 inches, covered with the same clay; then follows river clay covering unconformably the tertiary strata. Dip, towards east-north-east, at an angle of 15°.

The results of the analyses of a sample of each seam are as follow:

(3) The best outcrops are seen in the bed of the Nampyen near the village of Namma. It is not quite correct to say the " best" outcrops, because as regards the surrounding strata even less is seen of them than anywhere else; but there are unmistakeable signs that within the short distance of hardly a mile there are at least ten different coal-seams; and, if a conclusion as to the thickness of the seams may be drawn from the thickness of the lumps lying in the bed of the stream, none of them is less than 5 feet in thickness. The coal is of excellent quality, very hard, and of bright colour; and it can stand a considerable amount of wear and tear, as is proved by the fact that big lumps of fresh coal are rolled down stream amongst the big boulders of quartzite and porphyry without being smashed. However, the coal does not stand long exposure to water and air, as under their influence the laminæ of which the coal is composed become separated, and, together with the cleavage, the coal crumbles into small prismatic pieces. Dip, towards west-southwest at an angle of about 20°.

The following are the results of the analyses of five samples of the five biggest seams of the Nam pyen stream:

Although this coal is a bituminous coal, which should properly be called lignite or brown coal, it will certainly make an excellent fuel. I estimate the aggregate thick ness of the seams to be about 50 feet.

5. Alluvial deposits.—The causes which render the examination of the Lashro coal-field so difficult, namely the coat of alluvial deposits hiding the tertiary strata, are found to a higher degree in the Manzè-Namma coal-fields. The alluvial deposits consist here of a conglomerate which near Namma rests uncorformably on the coal-bearing strata. The conglomerate consists chiefly of rounded boulders of white quartzites and porphyries, and is very similar in appearance to that of the Mainglon valley. Near Namma the alluvial deposits reach the considerable thickness of about 200 feet, and they can easily be traced for a long distance, as they form a most distinct escarpment lining the slope of the hills to the east.

6. Extension of the Manzè-Namma coal-field.-It is nearly impossible to give a fair estimate of the extension of this coal-field, as the map of this part of the country is not reliable, and distances cannot, therefore, be measured. It can however be said that this coal-field has a larger extension than the Lashio field, as I received information afterwards that coal-seams are rather numerous farther down the Namma stream. It is, however, impossible to say for the present what breadth the coalfield has. Its length will certainly be not less than about 20 miles. The most favourable part of it is near the village of Namma, but it is possible that an equally good part may be found farther down the Namma stream.

SECTION VI.-ECONOMICAL VALUE OF THE COAL-FIElds.

Having discussed in the preceding sections the geological conditions and situation of the coal-fields it only remains to deal with the question as to whether these coal-fields in their present condition will be of any value. This question must be answered in the negative. The wealth stored up in these coal-fields will not be of any value so long as there is no communication by which it can be easily brought down to the Irrawaddi. The coal-fields are about 170 miles away from the next centre of traffic. The present road leading to them is only suited for carts for about 50 miles, after which pack animals must be employed. It need hardly be said that under these circumstances a profitable exploitation of the coal-seams is impossible. But even supposing that a road were made which would be practicable for carts all the year round, the coal-field could not be worked with profit. Coal that had to be transported by carts for about 170 miles would reach its destination, not only in very poor condition, but its selling price would be so increased by the cost of freight that it could not possibly compete with any other coal in the market.

It may therefore be said that as long as no other communication than the present one exists between the coal-fields and the plain of the Irrawaddi, the coalfields are of no value whatever, and will remain a dead treasure.

The exploitation of the coal-fields will only be remunerative when the cost of transport has been so much reduced that the coal from them can fairly compete with other coal, and the collieries will also need a local consumer on which to depend. Both these conditions would be fulfilled by a railway.

Now, the proposed railway line will cut right through the centre of the Lashio coal-field, and will pass the Namma coal-field so closely that a branch line could be constructed to it without much additional cost. The railway could therefore depend for its supply of fuel on the two coal-fields, and not on one of them, and this favourable circumstance would guarantee a sufficient supply of coal in the event of one or the other of the coal-fields not answering expectations.

It therefore remains to examine the conditions which have first to be considered before any mining operations can be started. The Lashio coal-field has certainly the advantage of thicker coal-seams, but it is still doubtful whether the coal is equal in quality to that of the Namma coal. It may be, but, as the case stands now, the Lashio coal is certainly inferior in quality to the Namma coal. As regards extension, the Namma coal-field is undoubtedly the larger one. It is, moreover, doubtful whether the Lashio coal-seams may be depended upon to any length, or whether they are not so broken and disturbed in bedding that mining operations could not be carried on profitably. This does not apply to the Namma coal-fieid, or at least to that part of it which is exposed near the village of Namma. Here regularity of bedding has been observed which would guarantee a certain extension of the seams.

The alluvial deposits in both the coal-fields would form a serious obstacle to mining operations; while the thick layer of clay in the Lashio field and the conglomerate in the Namma field would make the sinking of a shaft difficult. Again, owing to the peculiar way in which the coal-bearing strata are found a large quantity of water must be expected in both coal-fields. Finally, the climate of these valleys is feverish, and the health of the miners would therefore be severely tried.

Note on the reported Namsèka Ruby-mine in the Mainglon State, by Fritz Noetling, PH.D., Palæontologist, Geological Survey of India.

1. Situation of the mine.-Correctly speaking, the working which I am going to describe ought to be called the Namsèka Ruby-mine, because, from the name "Ruby-mines of Mainglôn" hitherto used, one might be led to believe that these mines are close to the town of the same name. However, nothing could be more erroneous than such a supposition, as there are no rubies within a considerable distance around Mainglôn. The mine is situated about 15 miles to the south-west of Mainglôn in the narrow valley of the Nampai, also known in its lower course as the Maddaya river. The exact locality where rubies are said to have been obtained lies about half a mile to the north-west of a small village called Namsèka, close to the junction of a small stream (called Namsèka) with the Nampai on the left bank of

the former. Its geographical position, according to the fifth edition of the preliminary map of Upper Burma, will therefore be Long. 96° 44', Lat. 22° 46'.

2. Geology. The greater part of the strata developed in the northern and western part of the Mainglôn State belongs to the gneissic and sub-metamorphic formations, as the latter is called in the Manual of the Geology of India; and the smaller part consists of recent river deposits of the alluvial system. No other formations have been found in that part of the country, the azoic rocks forming the hills, while the alluvial deposits fill up the valleys in different grades of extension.

(a) The gneissic formation.—The gneissic formation is as regards the country between Mainglôn and Mogôk, developed to the north of the Nampai, but in its western continuation it forms the hills on both sides of the Nampai. As regards the mineralogical character it may be said that the gneiss shows a Himalayan character, being of white or greyish colour, the common felspars being orthoclaes and albite. The gneiss is well-bedded and dips about 50° towards north. It seems to be traversed by eruptive granite, as, on the road between Mainglôn and Namsèka, large boulders of this rock can be observed for a short distance. Owing to the dense jungle, I could not, however, ascertain its exact relation to the surrounding gneiss, but it seened to me that it was true intrusive granite.

(b) Sub-metamorphic shales.-The sub-metamorphic shales covered a larger area. in the country which I examined than the gneissic formation. The hills to the south, east, and west of Mainglôn are formed by strata belonging to this group. The strata are represented by red and greenish shales frequently intersected by veins of milky quartz rock (? fault-rock). This group seemed to be much contorted, as the directions of dip changed frequently.

(c) Alluvial deposits.-The alluvial deposits consist of coarse and fine gravels, layers of big well-rolled boulders, and tough, brown gritty clay, which contains numerous angular grains of quartz rock. In the Namsèka mines these different constituents of river deposits do not change regularly; they are deposited without order and thus prove that they have been deposited by a torrent, and not by a large stream. The section of the strata in the pit gives a very good idea of this irregularity of bedding. At the farthest end of the pit, big boulders cemented by a coarse gritty clay are found, which are covered by a thick layer of fine brown clay A little nearer the river a bed of coarse clay is noticed at the same level as the large boulders, which is covered by a layer of gravel; the clay frequently contairs pockets of gravel and sand or big boulders. The strata thus clearly indicate the action of a torrent, which washed away at one place, say, the heavy boulders, while it deposited a pocket of sand; behind a protected corner the next heavy flood deposited large boulders again, which were covered by a layer of clay, and so on.

The pebbles and boulders chiefly consist of milky quartz-rock; gneiss or granite are scarce; there are occasionally some specimens of a black or blue silicious shale, but no traces of any limestone. The absence of limestone must particularly be noticed because the crystalline limestone is the original matrix of rubies.

These alluvial deposits are the ruby-bearing strata, but it is only in the sand or gravel that rubies are found, not in the clay. This proves clearly enough that the Namsèka rubies are not found in the original matrix, but that they, like the rest of the pebbles, sand, &c., have been transported by the water from some place higher. up the river, and (have been like the rest) deposited by the river along its course at localities which were favourable for the deposit. Having ascertained the nature of

the ruby-bearing strata; it was necessary to examine their extension, to find out whether they form a continuous bed along the banks of the river, or whether they were only deposited locally. This question was easily settled and it may be taken for granted that the river deposits do not form a continuous deposit, but that they are only found locally at places which were not only favourable for the deposit, but also protected the deposit once formed from being washed away again by the current. They therefore form mere pcckets of no great extension which may be found anywhere along the bank of the Nampai or of the Mogok stream. A description of the locality of the Namsèka ruby-mine will illustrate the nature of these pockets.

3. Description of the locality.-The Nampai, after having passed the broad valley of Mainglôn, has to cut its way through the gneissic rocks and the shales which form the hills west of the Mainglon valley, making its way in a meandering course through the hills; its valley is frequently a narrow gorge through which the foaming waters flow with tremendous rapidity, while at other places, where the valley widens out a little, the river forms quiet pools, sometimes of considerable depth. Just before reaching the place where the ruby-bearing sands are now deposited, the Nampai comes down with tremendous speed from the north-east, but is checked in its course by a promontory on its northern bank, round which it has to make its way, taking then a northerly course. Just opposite to the promontory, on the left bank of the river, there was a small ravine, the outlines of which can still be traced. Along the slope of the hills it seemed to have had a very narrow outlet towards the river, while it widened out in its upper part. This ravine being well protected against the torrent coming from the east, nevertheless afforded an easy access to the water from the north, the bar at its end being low; particularly when at high flood the water was rushed against the promontory, and, being unable to find its way through a narrow passage, was forced into the ravine on the opposite bank; the ravine was thus gradually filled up by the detritus of the Nampai. Subsequent floods may have partly washed away the deposits which were most exposed, while others may again have increased their quantity, but the bulk was deposited safely in the hollow of the ravine.

I estimate the height up to which the ravine was filled to be about 50 to 60 feet above the level of the Nampai at low water.

4. Description of the pit.-The pit was about 400 feet in length, contracting at its northern end to a narrow passage just sufficient to afford passage for one man ; it widened out to about 150 feet on the surface, but the bottom, where the men worked, hardly afforded room for two men to excavate the sand. The pit was therefore a funnel-shaped hole in which the workmen had to work under permanent danger of their lives, as the sides, not being supported by timber, might give way any moment, and fill up the whole pit.

(f) Manner of washing for rubies.-To facilitate the digging, the former workmen had constructed a small channel bringing the water to the top end of the pit where it was made to run down the walls, thus softening the hard clay. The workmen then put the sand or gravel into small baskets, which were brought down to the river, where they were put into flat baskets, and by a rocking movement in the water, the clay was first removed. If there were any stones of particular size they could then be noticed and picked out, the larger pebbles thrown away and the remainder carefully washed under a permanent recking movement. If repeated