AvuGusST I, 1912] 
NATURE 
551 
dency to disintegrate by slacking, gives the results 
of experiments from which it appears that coal of 
the kind tested (Illinois) rapidly reduces in size 
of lump with time. The change in calorific value 
was in all cases less than 2 per cent., and in one 
sample only 0°38 per cent. A number of other 
papers make up the volume, among which are 
nitric acid manufacture and sewage disposal. 
(4) On this sheet, measuring 40 x 30 inches, Mr. 
Marsh has plotted diagrams for designing and 
checking members of reinforced concrete under 
direct compression, according to the rules 
laid down in the “second report of the 
joint Committee appointed by the Royal Insti- 
tute of British Architects and the London County 
Council draft regulations. By means of the 
diagrams, it is possible to design the column or 
strut for a total load with an assigned ratio of 
longitudinal reinforcement, and to obtain the 
appropriate hoop reinforcement. The diagrams 
will thus prove valuable for engineers designing 
' compression members in reinforced concrete, and 
the only criticism that might be made would be 
the somewhat bulky form of the sheet. As the 
results of -using the diagram would be in 
accordance with the above regulations, its utility 
ought to be quickly recognised by busy engineers. 
(5) The introduction of electric and electro- 
pneumatic signalling arrangements on railways 
has given rise to a special branch of engineering, 
and it is to the engineers and students engaged 
in that department that Mr. Lewis addresses this 
volume. It will not appeal to engineers generally, 
though there is much ingenuity displayed in the 
design of modern signal systems which would 
attract a man with a mechanical turn of mind. 
The book is illustrated by excellent drawings, and 
the descriptive matter is well chosen. The author 
is lecturer on railway signalling at the Glasgow 
and West of Scotiand Technical College, and is 
on the staff of the Caledonian Railway. 
KAINOZOIC STRATIGRAPHY. 
Traité de Géologie. By Prof. E. Haug. II., Les 
Périodes géologiques. Fascicule 3. Pp. iv+ 
1397-2024. (Paris: Armand Colin, 1908— 
1g11.) Price 11 francs. 
HE third fascicule of Prof. Haug’s “ Traité 
de Géologie” completes this valuable text- 
book with an account of the post-Cretaceous | 
The author’s treatment of the sub- | 
formations. 
ject, as in the previous parts, is marked by the 
special importance given to the varying bathy- 
metric conditions under which different parts and 
areas of a formation have been laid down. The 
NO. 2231, VOL. 89] 
present volume is also of interest as it presents a 
modern French classification of the post-Cre- 
taceous rocks. Prof. Haug does not use the 
term Kainozoic, and does not adopt any one term 
for these formations. He divides the post- 
Cretaceous time into three eras: the Nummulitic, 
the Neogene, and the Quaternary. He has aban- 
doned the generally accepted five periods, and 
rejects Lyell’s nomenclature altogether. British 
geologists will probably not follow this course 
unless the reasons for the change are quite con- 
vineing. 
The Nummulitic and the Neogene are grouped 
together by Prof. Haug as the Tertiary, and both 
its lower and upper limits are ill-defined. He 
includes the Montian in his Nummulitic, and he 
explains its rich fauna of Cretaceous bryozoa and 
brachiopoda in the Tuffeau de Ciply as fossils 
derived from older limestones. As the Danian is 
left in the Cretaceous, the author admits an im- 
perceptible stratigraphical boundary between the 
Cretaceous and the Nummulitic, in spite of the 
sudden change of fauna. Both the two divisions 
which Prof. Haug refers to the Tertiary he divides 
into three sections. His Eo-Nummulitic includes 
the Montian, with the Thanetian and the Lon- 
donian, of which the typical deposits are the 
Lower London Tertiaries. The Meso-Nummulitic 
ranges from the Lutetian to the Ludian, the sec- 
tion above the Barton clay. He rejects the 
Priabonian as a widespread horizon, and appears, 
on p. 1475, to limit it to the Alps, though he sub- 
sequently accepts it in North Africa; and its 
presence with other Nummulitic rocks in 
Cyrenaica, as shown since the publication of the 
volume, renders necessary the alteration of the 
statement (p. 1503) that there is no vestige of the 
Nummulitic sea between Egypt and Tunisia. The 
Neo-Nummulitic is practically the Lower Oligo- 
cene, and Prof. Haug quotes Tongrian and Oligo- 
cene as synonyms. 
The three sections of the Nummulitic are sub- 
| divided into ten divisions, and the author con- 
veniently gives the founder, etymology, and date 
of the name of each. The classification of the 
Nummulitic is based mainly on the foraminifera, 
and though Prof. Haug remarks that it may 
appear somewhat paradoxical to attach such 
weight to these primitive organisms, they are cer- 
tainly among the most convenient fossils in the 
correlation of the Lower Kainozoic horizons. 
The Neogene group Prof. Haug divides into 
| three sections, and owing to the great import- 
ance of their representatives in the Mediterranean 
area, he calls them the Eo-Mediterranean, Meso- 
Mediterranean, and Neo-Mediterranean (p. 1607). 
