

TRANSACTIONS OF SECTION E. 423 



of commerce in all parts of the world. When it is remembered how much 

 depends upon the work of marine surveys, it must he a subject of astonishment 

 that so many hundreds of miles of coast line frequented by our shipping remain 

 unsurveyed ; and that even, in some cases, when the surveys have been executed 

 and charts published by foreign governments, they are not accessible in an English 

 form. In the interests of humanity and of the well-being of our trade, the 

 efforts of geographers in urging the completion of marine surveys ought to 

 be cordially seconded by Chambers of Commerce, and by all those whose material 

 interests are concerned in the provision of accurate charts of all coasts visited by 

 our shipping. 



Hitherto I have invited your attention to the basis of geography, to the 

 measurement of the surface of land and sea, and of their heights and depths ; to 

 the mapping of the world, and to the innumerable uses of maps and charts. But 

 this only forms the skeleton of our science, which is endued with flesh and blood, 

 with life and motion, by those who study the causes and nature of the changes 

 that have taken place and are now taking place upon the earth ; by comparative 

 and physical geographers, by those who study and classify natural phenomena, 

 and demonstrate their connection with each other and tbeir places in the great 

 scheme of nature. 



Geography and geology are, from one point of view, sister sciences. The 

 former treats of the earth as it now is and of changes which have occurred within 

 historical times. The latter deals with the condition of the earth and the changes 

 on its surface which went on during the cycles of ages before the dawn of history. 

 The two sciences are quite distinct, while they aid each other. No geological 

 survey can be undertaken without the previous completion of geographical maps, and 

 the geologist is enabled to comprehend the condition of the earth in remote ages 

 by studying the phenomena of physical geography. On the other hand, the 

 geographer acquires a correct understanding of the present state of the earth's 

 surface by considering the records of those marvellous changes which can be 

 gathered from history and from the narratives of travellers and observers in all 

 ages. Without their services, geography would lose half its interest. 



Comparative geography (the study of the changes which have taken place on 

 the earth's surface within historical times) is, therefore, a most important branch of 

 our science ; and it enlists the historian and the topographer in our service. It is 

 a branch of geography which has not hitherto received the amount of attention 

 it deserves. 



The importance of the study of history and of early narratives for the elucida- 

 tion of points in physical geography will appear from the consideration of a few 

 instances. Take for example the great and fertile basin of the river Ganges in 

 India. The Sanscrit historian finds reason for the belief that in 3000 B.C. the only 

 habitable part of the alluvial plain of India was the water-parting or ridge between 

 the Sutlej and the Jumna. The rest was a great estuary or arm of the sea. It 

 has only been fit for man's occupation within the historical period, and hundreds of 

 square miles of the delta have become habitable since the days of Lord Olive. 

 The wonderful history of these changes can be traced by the student, who thus 

 enables the geographer to explain the phenomena which he observes. Mr. Blan- 

 ford, in his charming work on physical geography for the use of Indian schools, 

 supposes a native of the country to be standing on the bank of the river 

 that flows by his village, watching the turbid flood swirling past. The chur 

 opposite, which the river left dry when its waters fell at the close of the last rainy 

 season, and which, till lately, was covered by a rich green crop of indigo, is now 

 more than half cut away, and buried beneath the water. Masses, many times 

 larger than the house he lives in, from time to time detach themselves, and are 

 swallowed up by the deep muddy stream. If the Hindu ponders over what he sees 

 he will perhaps be led to make inquiries, and old people will probably tell him that 

 half a century ago the river itself was a moderate sized khall, and that the old 

 channel, seven or eight miles oft", now little more than a string of pools, was at 

 that time a great river. These facts and their causes will open to him an in- 

 teresting chapter in physical geography ; which is made more complete and more 



