May 10, 1901.] 
The Report of the Chief of Ordnance, proper, 
is a very brief, business-like and well-condensed 
summary of the operations of the bureau for the 
fiscal year ending June 30, 1900, covering 42 
pages of the volume. The details of the work 
are exhibited in the remaining four hundred 
pages, in which are given forty appendices, 
mainly reports of officers charged by the Bureau 
with important duties and including the opera- 
tions of the various arsenals. 
Watervliet Arsenal, for example, has turned 
out during the year 45 ten- and twelve-inch 
rifles and mortars, and five smaller rapid-fire 
guns, and has madea large quantity of accessory 
material. Springfield Armory made about 60,- 
000 army rifles and carbines and attained an 
output of 400 gunsa day. Working eight hours 
a day, it now turns out about 200. As usual, 
a large amount of experimental work has been 
performed. Watertown Arsenal has been en- 
gaged upon sea-coast gun-carriages and its 
great testing-machines—it now has one of 200,- 
000 pounds capacity, in addition to the older 
machine of 80,000 pounds—have performed a 
considerable amount of valuable scientific work 
in addition to that of the routine operation of 
the Department. Frankford Arsenal has made, 
during the year, 23,000,000 small-arm car- 
tridges and can now issue about 90,000, per 
day of eight hours, continuously. Rock Island 
Arsenal turns out most of the infantry and 
cavalry equipments of the army. It makes 
blanket-bags at from $1 upward, haversacks at 
from 85 cents, canteens at 32 to 38 cents and tin 
cups cost but 10 cents to make. Costs have 
come down and wages gone up with the use of 
improved machinery. A newsmall-arms factory 
is under construction here, to produce 200 to 
250 guns a day. Heavy guns for fortifications 
have been so extensively supplied that the De- 
partment is now turning its attention to the 
smaller rapid-fire guns. A muzzle velocity of 
3,000 feet per second is to be attained in the 
later construction. 
Wire-wound guns continue a subject of ex- 
periment, but still without complete success. 
It has come to be a question whether the dis- 
appearing gun-carriage for heavy mounts is 
best practice and whether it has not been too 
exclusively adopted. The Bureau does not 
SCIENCE. 741 
express a decided opinion on this point. The 
automatically operating rapid-fire gun is re- 
ported upon and recently invented automatic 
pistols are the subject of investigation, with the 
result of choice of the Colt construction for 
army use, if later approved by the Department. 
Interesting investigations of the composition 
of acceptable gun-steels give the valuable de- 
duction that for an elastic limit of 70,000 to 
75,000 pounds per square inch, and a tenacity 
of 100,000, with an elongation 15 to 20 per cent., 
the compositions should include about one-half 
of one per cent. carbon, one per cent. manga- 
nese, one-fifth to one-tenth per cent. silicon, and 
well under one-tenth of one per cent. of sulphur 
or phosphorus. Oil-tempering is not of advan- 
tage. Rolling is best performed at a temper- 
ature a little way below that of the blue 
‘critical heat.’ One curiously interesting de- 
duction is that the action of smokeless powder, 
or other high explosive, attaining a given pres- 
sure in the barrel of a gun, is less destructive 
than a similar pressure produced by ordinary 
static testing. The duration of the pressure is 
about 0.0004 second only, and time is thought to 
have an important influence upon results. The 
normal powder pressure in the army rifle is 
about 42,000 pounds per square inch. The 
singularly interesting phenomenon, extensively 
investigated by the writer many years ago, 
‘the exaltation of the normal elastic limit by 
strain,’ * finds application here, as in so many 
other matters of applied science ; the practice 
being now established of rolling and forging 
parts at a minimum temperature to insure high 
elastic limits and maximum tenacity. 
R. H. THURSTON. 
Experimental Psychology. A Manual for Lab- r 
oratory Practice. By EDWARD BRADFORD 
TITCHENER. Volume I. Qualitative Experi- | 
ments; Part I. Student’s Manual, Pp. 214. 
Part II. Instructor’s Manual. 
New York, The Macmillan Co. 1901. 
The place of laboratory practice in the teach- 
ing of psychology has, in’American universities 
at least, become assured. It is by no means 
* Trans. A. S.C. E., 1873. ‘ Materials of Engineer- 
ing,’ Vol. II., Chap. X.; Vol. III., Chaps. XIII., 
XIV.—R. H. T. 
Pp. 456. - 
