^OLIAN FORMATIONS. 93 



far from the highest part of the teri, it follows, therefore, that the teri 



has been deposited upon and around a mass of marine limestone elevated 



not much less than 2.00 feet above sea level, consequently the true 



thickness of the mass of red sand is certainly in parts very much less 



than the apparent mass. 



The great teri north of Megnanapuram, also known as the Kudirai 



,, 4. • r.r. Moli, is rather larger in superficial extent than the 



MegnaBapm'am ten or ^ & r 



Kudirai Moli. Ittamoli teri just described, but it is less elevated, 



and showed at the time of my visits (in January 18S3) many fewer 

 signs of recent movement of the sandwaves. It also appeared to me of 

 a rather less vividly red colour than any of the other large teris. 



Here too there are signs that the sand rests in part at least on 



an elevated mass of the marine sandstone series. 

 Thickness of the teri. r-, .-,, t ^ • , -, -n i p , ,• , ,^ 



Still i think it will be sate to estimate the maxi- 

 mum thickness of the sand at somewhat over 100 feet. 



Kudirai Moli, as this teri is called on the map accompanying the 



District Manual, shows markedly a phenomenon 

 Drainage of the teri. - n . i - • i xi • • it 



common to all the tens, namely, the issuing irom 



their base of springs of some size due to the percolation from above of 

 all the rain falling on the surface. It is only in exceptionally heavy 

 rains that any water flows off the surface of the sands : all other rainfall 

 is absorbed at once and flows out around the base quietly and continu- 

 ously. Along the northern side of the Kudirai Moli advantage is taken 

 of these springs, and channels are excavated to some depth, sometimes 

 as much as 12 feet or more, to meet these springs and conduct their 

 water for irrigation purposes to fields and gardens in the neighbourhood. 

 These channel sections reveal that in many places the percolation of the 

 rain water has given rise to a cementation of the mass of ferruginous 

 and silicious particles into a quasi-lateritic agglomerate. 



The teris north of the Tambraparni river are quite small and unim- 



Teris north of the portaiit Comparatively speaking. The little teri 



Tambraparui. north of Panavalli church is low and ill-defined. 



The next to the northward, which lies not far west of the large mis- 



( 93 ) 



