VISUAL REQUIREMENTS OF SATLOR AND RAILWAY EMPLOYEE. 263 
the outset of their career, since one complete ophthalmological 
examination at that period of life will enable the future vision of the 
examinee to be predicted with tolerable certainty. 
Tt will be seen that the method adopted by the Victorian Railways 
would eliminate those who have a high degree of hypermetropia; but 
it may admit those suffering from choroiditis with contracted fields, 
from glaucoma, and, in fact, any eye disease which is not obvious and 
which has no lowered central form vision. 
Stress need hardly be laid on the injustice perpetrated in allowing 
anyone to enter a seafaring life, to spend some years in acquiring pro- 
ficiency, and then subject him to a visual examination when he makes 
his appearance for his first professional examination. The sensible 
course is obviously to insist on a complete examination when the boy 
first goes to sea. 
Dry-Farming Investigations in the United States. By Lyman Ji: 
Barieds, M:iS:, Ph.D: 
[Pratre V.] 
(Ordered, on behalf of the General Committee, to be printed in eatenso.) 
Tur term ‘dry-farming’ is now generally applied to agricultural 
practice in regions where rainfall is the primary limiting factor in 
crop production. The determination of the tillage methods which are 
most efficient in the storage and conservation of moisture, and the 
development of varieties which are especially suited to dry-land con- 
ditions, are economic problems worthy of the best efforts of the 
agronomist. The most efficient methods are not always the most 
profitable methods, for the margin of profit in dry-farming is normally 
small, and the cost of tillage must always be compared with the 
return. Efficiency in the use of the limited rainfall is, however, the 
basis upon which dry-farming practice must be built. 
Before taking up the discussion of dry-farming investigations in 
the United States, a word regarding the organisation of the Depart- 
ment of Agriculture in this connection may be of interest. Five 
offices in the Bureau of Plant Industry are devoting a large part of 
their energies to dry-farming problems. The Office of Dry-Land 
Agriculture operates over a score of experimental farms in various 
sections of the Great Plains. This office is concerned chiefly with the 
determination of the crop rotations and tillage methods which are best 
adapted to the various dry-farming sections. It was early recognised 
in the development of this work that dry-farming problems are often 
of an extremely local character, and that numerous experimental 
stations are necessary to cover the field. Fach experimental farm is 
superintended by a trained agriculturist, usually an agricultural college 
graduate. These farms also afford experimental facilities for other 
offices engaged in dry-farming problems. The offices of Cereal Investi- 
gations, Forage Crop Investigations, and Alkali and Drought-Resistant 
Plant Investigations are engaged in the investigations of crops suited to 
