CLYDE SEA AREA. 



651 



as the water surface. Loch Strivan and the Gareloch have the average ratio for the 

 whole Sea Area, their drainage basin being three times as large as their water surfaces, 

 while Dunoon Basin, Arran Basin, and the Estuary (excluding Loch Lomond and the 

 Clyde) have a ratio of 2 or less. This serves as a measure of the extent to which 

 the physical conditions of the water in the various basins are subject to the meteoro- 

 logical variations of the land surface. 



The calculation of the volume of the various basins is founded on the low tide 

 soundings recorded on the Admiralty charts. From the charts sections were drawn on 

 millimetre logarithmic paper, a longitudinal section being made in the first instance along 



Table I. — Drainage Areas and Ratio to Water Surface in Square Miles. 



Basin. 



Water 

 Surface. 



Land 



Drainage. 



Total Area. 



Ratio. 





W. 



L. 



T. W. 



L. : T. 



Gareloch, .... 



4-23 



12-40 



16-63 1 



2-93: 3-93 



Loch Goil, .... 



3-36 



33-85 



37-21 1 



10-07 : 11-07 



Loch Long, . 



4-18 



29-10 



33-28 1 



: 6-96 : 7"96 



Holy Loch,* .... 



1-60 



72-52 



74-12 1 



: 45-32 : 46-32 



Loch Strivan, &c, . 



11-88 



36-92 



48-80 1 



: 3-11 : 4-11 



Loch Ridun and Kyles, . 



10-00 



67-24 



77-24 1 



: 6-72 : 7*72 



Loch Fyne, .... 



28-44 



188-44 



216-88 1 



: 6-62 : 7"62 



Dunoon Basin, 



47-64 



86-36 



134-00 1 



: 1-81 : 2-81 



Clyde River (to Bowling), 





1143-20 



1143-20 



... ... 



Estuary (excl. L. Lomond), 



26-80 



60-16 



86-96 1 



2'24 



3-24 



Loch Lomond, 



27-72 



266-92 



294-64 1 



9-63 



10-63 



Arran Basin, .... 



685-00 



1071-10 



1756-10 1 



1-59 



2-59 



Great Plateau, 



Total, .... 

 * Including Loch Eck, 



313-48 



282-50 



595-98 1 



0-90 



1-90 



1164-33 



3350-71 



4515-04 1 



2-88: 3-88 



1-60 



38-08 



39-68 1 



23-80:24-80 



the axis of maximum depth, the scale of depth being exaggerated fifty times in comparison 

 with that of length. Cross-sections at right angles to the axis were made at the position 

 of each observing station, and when necessary at intermediate points, so as to divide up 

 each basin into a number of short portions, the coast-lines of which were comparatively 

 regular. In many cases the cross-sections, in addition to being drawn on the same scale 

 as the longitudinal sections, were produced on a true scale of heights and depths. This 

 afforded an opportunity of checking the calculations of the area of those cross-sections. 

 Representative examples of the longitudinal and transverse sections are given in Plates 

 VII, VIII. , IX., and the more important of the corresponding lines are laid down on 

 the map (Plate I.) with references. 



The mean of the area of two neighbouring cross-sections multiplied by the distance 

 between them gave approximately the volume of the portion, and the sum of all these 

 portions — the cross-sections varying in number from two in the case of the Holy Loch 



