MISCELLANY. 



503 



Matarity of Timber-Trees. A paper in 

 the " Transactions of the Scottish Arbori- 

 cultural Society" contains the following in- 

 formation with regard to the time required 

 for various kinds of timber-trees to reach 

 maturity : "Tie oak can never be cut down 

 so profitably when small as when well ma- 

 tured, and having plenty of heart-wood. 

 The timber is seldom of much value until 

 it has reached the age of 100 years. Ash 

 can be Jut down more profitably in its 

 young state than other hard-wood trees. 

 When clean grown, and from thirty to 

 forty years of age, it is in great demand 

 for handle-wood and for agricultural imple- 

 ments. Beech is of very little value in its 

 young state, and is seldom cut till well 

 grown. Birch can be cut down profitably 

 at about forty years old. Horse-chestnut, 

 when grown on good soil, and in a shel- 

 tered position, can be profitably cut down 

 when it attains large dimensions. Elms 

 (Scotch and English) should never be cut 

 until they are from eighty to one hundred 

 years old. Poplars can generally be profit- 

 ably sold when about fifty years old. Syca- 

 more, growing in good soil, may be profit- 

 ably cut down when about one hundred 

 years old." 



Source of the Nitrogftn used by Plauts. 



The average life of an apple-tree in Nor- 

 mandy is estimated by M. Isidore Pierre at 

 fifty years, and its nitrogen product (in 

 leaves, fruit, wood, and roots) at 26 kilo- 

 grammes (about 60 pounds). This amount 

 of nitrogen corresponds to 5,200 kilo- 

 grammes of farm manure, or 100 kilo- 

 grammes per year. But the tree is far 

 from receiving any such amount ; accord- 

 ing to the author, the most liberal culti- 

 vator does not supply more nitrogen than 

 is found in the seeds. The question then 

 arises. Whence comes the remainder of this 

 nitrogen ? M. Thenard, in a communication 

 to the Paris Academy of Sciences, denies 

 that it comes directly from the soil, or from 

 the manure, and holds that it is derived 

 from the air through the soil. In confirma- 

 tion of this, he cites the grape-vines of Clos- 

 Vougeot, the youngest of which were plant- 

 ed in 1234, and which annually receive only 

 one kilogramme of manure. The amount 

 of nitrogen contained in this quantity of 



manure is inconsiderable, as compared with 

 what is contained in the grapes, the leaves, 

 and the wood. 



Crania] Measurements. Two noteworthy 

 results of the comparative measurements of 

 the crania belonging to historic and pre- 

 historic times were dwelt upon by Prof. 

 Rolleston, in his presidential address to the 

 Section of Anthropology, at the last meet- 

 ing of the British Association. It might 

 be assumed that skulls from the earliest 

 sepulchres would present the smallest ca- 

 pacity, and that the size of the brain-case 

 has since increased with the intellectual de- 

 velopment of our race. But this assump- 

 tion is curiously contradicted by the facts. 

 Indeed, the cubic contents of many skulls 

 from the oldest known interments consid- 

 erably exceed the capacity of modern Euro- 

 pean skulls of average build. Surprise at 

 such a result may, however, be tempered 

 by the reflection that the skulls which we 

 have obtained from the earliest tumuli are 

 probably those of the chiefs of their tribes, 

 who may have been selected by virtue of 

 their great energy. Nor should it be for- 

 gotten that in savage communities the chiefs 

 come in for a larger share of food, and are, 

 consequently, men of well-developed frames, 

 and of more portly presence than their fel- 

 lows. As to the poorer specimens of hu- 

 manity in those days we probably know 

 nothing, as they were denied burial in the 

 tumuli, and have left their remains we 

 know not where. Another curious fact is, 

 that the female skulls from the earliest 

 sepultures do not differ in capacity from 

 the contemporary male skulls to the same 

 degree as the crania of the two sexes differ 

 at the present day. But it must be borne 

 in mind that in those early times there was 

 a greater struggle for existence, and that 

 the division of labor was not carried out to 

 a large extent, so that the tendency to a 

 differentiation of the crania was less marked 

 than in modern times. 



An Indian Mill. On the farm of Mr. 

 HoUis Smith, near Marengo, Calhoun Coun- 

 ty, Michigan, there exists an interesting 

 monument of aboriginal life, known in the 

 locality as " The Indian Mill." As described 

 in a letter to us by Mr. W. H. Payne, of 



