tion is given concerning the methods of breeding 
and management which are adopted in America. 
Beef and dairy cattle are treated separately, and 
the breeds referred to include the Guernsey, Jersey, 
Ayrshire, Shorthorn, Aberdeen Angus, Galloway, 
Red Poll, and Devon, and among continental 
breeds the Dutch Belted, Holstein-Friesian, and 
Brown Swiss cattle. The sheep mentioned are the 
Merino and the majority of English breeds. Ina 
section on the breeding of the ewes, it is said that 
“some owners hold the ewes while the ram serves 
them; then in a few days the ewes come around 
naturally, when the ram serves them again in the 
natural way.” It is difficult to conceive what pos- 
sible advantage can accrue to this practice, but 
the author says nothing in disapproval of it. In 
dealing with pigs he separates the lard type from 
the bacon type, since these are so different in 
character. The lard type greatly outnumbers the 
bacon type in America. It is interesting to note 
that the Poland China breed, which represents the 
extreme limit in lard production, is in consequence 
lacking in fecundity. The operation of castrating 
pigs is described, but there is no mention of 
ovariotomy, which is practised in various parts of 
the British Isles. 
The volume contains good illustrations of prize 
animals belonging to the different breeds, and 
to these are often appended explanatory descrip- 
tions or other interesting information. To English 
agricultural readers the work is instructive as 
throwing light on the conditions of farm practice 
which prevail in America. 
Francis H. A. MARSHALL. 
TECHNOLOGY AND LITERATURE. 
The Theory and Practice of Technical Writing. 
By Prof. Samuel C. Earle. Pp. vii+3or. 
(New York: The Macmillan Co.; London: 
Macmillan and Co., Ltd., 1911.) Price 5s. 6d. 
net. 
OW far it is possible for the technical man 
to acquire facility in the presentation of 
his subject by a system of rules laid down by an en- 
thusiastic teacher must always be open to doubt, 
and everyone is, after all, the architect of his own 
style. But much may be done by judicious arrange- 
ment and example, and the author (an American 
professor of English literature) has certainly set us 
a good example in this well-written book. The 
difficulties to be met in writing for the whole field 
covered by ‘technical writing ”’ are overcome by 
separating the various kinds of technical litera- 
ture, and dealing with each according to its 
special requirements. Different treatment is 
necessary for such various kinds of literature as 
the condensed statement of a patent specifica- 
NO. 2218, VOL. 89] 
x Supplement to “ Nature,’ May 2, 1922. 
tion, the report of a resident engineer upon his 
work, or the presentation of a great subject at 
the hands of a master. 
Various examples drawn from engineering 
books by well-known authors and published reports 
are given in a long appendix to illustrate points 
in the text. The description of the transit (or 
theodolite, as it is known to English engineers) 
and Bleriot’s account of his cross-Channel flight 
represent the opposite poles of technical descrip- 
tion. While the one is terse, and is shorn of 
all but a skeleton of words, the latter is florid, 
imaginative, and altogether unlike the calm de- 
scriptive writing that we would look for in our 
technical papers. But French writers are always 
more lavish with words, and the beauty of their 
language makes redundancy less noticeable than 
in English. 
The two chapters on “addressing general 
readers’ and ‘addressing specialists” contain 
much condensed wisdom and many useful hints 
to those who would address a larger circle of 
readers than the specialists. Indeed, the spread 
of scientific and technical knowledge among the 
general public depends in no small degree upon 
the absorption by technical writers of the axioms 
contained in these two chapters. A_ correct 
diagnosis of the state of special knowledge among 
the readers that a writer would address is the 
passport to success. Though ornamentation is 
often out of place in technical literature, the 
author does not inhibit “picturesque language, 
concrete illustrations, contrasts, paradoxes, and 
figures of speech,’ which in moderation may 
stimulate interest in a dry subject, or suggest 
collateral lines of inquiry. Yet, as he says, most 
technical writers avoid such “literary” qualities. 
We would wish that it was possible for the 
author to impart to his students his graceful, 
simple, and convincing style as easily as he 
presents his arguments for the arrangement, 
classification, and balance of their work. The 
young writer will feel encouraged by a quotation 
from one who was himself an effective writer and 
a most successful teacher that “success as a 
writer depends upon his willingness to fill a waste 
paper basket if necessary before producing a 
single finished page.”’ How far the success of 
great teachers depends upon ability to write 
easily and in an entertaining manner is familiar 
to those who have profited by monumental text- 
books. The works of Clerk Maxwell may be 
cited as an instance of great literary charm com- 
bined with cogent reasoning, and a careful 
perusal of the work before us will show that 
these are not antagonistic, but complementary 
qualities. RS se 
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