24 



THE MUSEUM. 



and their melodious voices they can 

 make night as hideous as you please. 

 They are always happy and glad to 

 see strangers, and will accept anything 

 you offer them or anything you care- 

 lessly leave around. It is very pleas- 

 ant to be entertained by a lot of them 

 and they take great interest in your 

 wares especially a freshly made up 

 bird skin or something that can be 

 broken in handling. They will stay 

 with you at camp as long as your 

 larder is full and will cheerfully allow 

 you to bring all the wood and water, 

 do all the work around camp, occupy 

 your seat and put things where you 

 can't find them. They know the 

 names of all the birds and have them 

 well classified as will be seen when I 

 say they have the Woodpecker and 

 Mockingbird in the same family. 

 They seem to be glad they are living 

 and really they ought for they want 

 for nothing, except for more Natural- 

 ists. A good collecting place is right 

 among them as the birds and animals 

 seem to come out of the thickets to 

 mingle with the natives. Only a few 

 days since a Jaugar carried off a burro 

 near town in daylight. 



"I find a great many tropical spec- 

 ies here whose habitat is given farther 

 south, and so far many species that I 

 have not been able to identify from 

 the books of my own. These I shall 

 hope 1o cover in a later letter. 



Glaciers of Greenland. 



The following entertaining and in- 

 structive article from the pen of Prof. 

 Thomas Chamberlain, head of the de- 

 partment of geology of the University 

 of Chicago, who accompanied Lieut. 

 Peary's last expedition to the far north. 



recently appeared in the New York 

 Commercial Advertiser. 



The study of Greenland glaciers, 

 says the professor, has a specific bear- 

 ing upon one of the most widespread 

 and important of our geological for- 

 mations. The larger portion of six- 

 teen of the northern states and small- 

 er portions of eight or ten others are 

 covered by a mantle of clay, sand, and 

 gravel, filled with bowlders transport- 

 ed from the north. This mantle 

 forms the sub-soil of about one-third 

 of the cultivated portion of the United 

 States and a very large part of its fer- 

 tility is dependent upon this. The 

 spreading of this mantle over these 

 States very much subdued the topo- 

 graphy and thereby rendered the con- 

 struction of railway lines and other 

 means of transportion easy and econ- 

 omical where they would 'otherwise 

 have been difficult and expensive, and 

 in some cases impracticable. Many 

 lines owe their existence to the smooth- 

 ing down of the surface brought about 

 by this formation. 



The explanation of this deposit, 

 which is know as the "drift," has been 

 one of the most difficult problems of 

 geology, and probably more has been 

 written upon it than upon any other 

 single topic in the whole range of sci- 

 ence. It was formerly attributed to 

 great floods sweeping down from the 

 north. Later it was quite generally 

 referred to icebergs floating over the 

 region during a state of submergence. 

 It is now generally attributed to gla- 

 ciers that are believed to have covered 

 nearly one-half of North America, 

 reaching southward as far as New 

 York, Cincinnati, St. Louis and Kan- 

 sas City. It is only in Greenland and 



