132. JOURNAL, NATURAL HIST. SOCIETY OF SIAM. Vol. I. 
country) it appears that trips of more than two weeks duration neces- 
sitate a considerable force engaged in bringing up supplies from a base. 
As no description of this part of the country, so faras Iam 
aware, has ever been given, it may be of interest if I shortly describe it. 
The Petchaburi river, as it trickles beneath the bridge at the 
town of Petchaburi in the dry season, is an insignificant looking 
stream, and gives little indication of the fact that its course is upwards 
of 80 miles in length, draining an area of 1200 square miles, 600 of 
which are mountains of considerable elevation in the direct line of the 
5. W. monsoon. 
The source of this river is in N. Lat. 12° 40,’ E. Long. 99° 20,’ 
this point being the birthplace of two other big streams:—the Huey 
Sat Yai (Big Beast river) which flows East into the Pran river, and 
the Cha-ra-wah flowing West into the Tennasserim river. From it® 
source the Petchaburi river flows due North for 20 miles to the 
Klephant’s Tusk rapid, where it is joined by the Menam Bang Kloi, 
which latter has its source some 17 miles to the N. W. The ground 
level at the junction ig 145 metres above sea level and the boundary is 
distant westwards some 10 miles or four days’ march. 
The Elephant’s Tusk is an impassable rapid for dug onts,—the 
banks being precipitous there is no opportunity, as at other bad rapids, 
of dragging the canoes through overgrown shallows at the sides of the 
main stream. 
From this point the river flows some 18 miles due East when 
the first Kariang hamlet is reached, viz:—Ta Ling Lom (Wind monkey 
landing) and a further 12 miles EK. S. E. carries one to Sarahett. Here 
the river makes a sharp bend and flows due N. EH. to Petchaburi town. 
The northern portion of this area is drained by the Meh Pachee 
river which rises with the Bang Kloi in N. Lat. 13° 10’ and flows due 
North some 50 miles where it joins the Quaa Noi. 
The area to the south of the Petchaburi watershed is drained by 
the Pran river, the source of which lies some 10 miles N. E. of the 
source of the Petchaburi river and about 10 miles on the Eastern or 
Siamese side of the boundary range. 
All these three rivers for the first 20 miles of their courses lie 
in deep gorges, together with their hundreds of tributaries. Only 
occasionally dosmall flats occur in the bottoms, and these are seldom 
of any extent. The greatest altitude found was 1505 metres (5000 ft.) 
