574 

light, as held in electric substandard lamps, and with 
the estimation of high temperatures by a method of 
colour identity. Reference may here also be made to 
the first report issued by the Committee on the Light- 
ing of Factories and Workshops, of which the director 
of the laboratory is chairman. In the direct-current 
division good advance is reported with the research on 
the heating of buried cables. 
With the co-operation of Dr. Schultze, two standard 
resistance thermometers, the constants of which had 
been studied at the Reichsanstalt, were re-examined 
at the laboratory. Owing to the war, no official com- 
parison of the Reichsanstalt and the laboratory figures 
has been possible; but the two sets are known to be 
in close agreement. In a revision of the high-range 
mercury standard thermometers valuable assistance 
was given by Dr. René Paresce, of the Bureau des 
Poids et Mesures. The heat division was also occu- 
pied with research on refractory materials and on heat 
loss from surfaces. 
In the metrology division the silica standard metre 
was kept under close observation, and it is promising 
to hear that no measurable extension could be de- 
tected during the year. Other items of interest are a 
series of rulings, undertaken for Prof. W. H. Bragg, 
to illustrate his work on X-ray spectra, and a report 
issued to the Board of Trade on leather-measuring 
machines and templates. ; 
In spite of the absence of Dr. Kaye on active ser- 
vice, the radium division flourished during the year. 
Samples amounting to the value, 35,o00l., were sub- 
mitted for test; up to March, 1914, the corresponding 
figure was 3000l. The division promises to thrive. 
Not more than a broad selection can here be made 
from the numerous investigations of the engineering 
department. These range from experiments on the 
resistance of materials to alternating shear and com- 
bined stresses to an examination of cracks in the 
Tower of London. Considerable progress was made 
with a research on the methods of notched-bar impact 
testing, which is mainly concerned with a determina- 
tion of the correct relation between the mass of the 
hammer, the velocity of striking, and the linear dimen- 
sions of the specimen, in order that tests on similar 
specimens on different scales may yield consistent 
results. Attention may also be directed to a report 
on power transmission through motor gear-boxes. On 
varying the quantity and the viscosity of the oil in 
such boxes, surprising alterations in efficiency were 
observed. Passing to the aeronautical division, the 
new 7-ft. wind channel is now in full working order. 
The researches of this division on the longitudinal and 
lateral stability of aeroplanes are well known, and 
call for no review here. 
Interesting profiles of road surfaces at various 
stages in test were obtained by the Road Board labora- 
tory, and numerous road materials examined under 
the microscope and otherwise. 
Of the work accomplished during the year by the 
department of metallurgy, it must suffice to instance 
important researches on the constitution of aluminium- 
zinc-copper and copper-tin alloys, and an investiga- 
tion of a new reagent for etching steel. Mention 
should also be made of some tests carrie@ out by the 
chemical division on optical glasses, and of a report 
issued to the Board of Trade giving the results of an 
investigation into the precautions necessary in the 
transport of barium peroxide at sea. Some serious 
fires at sea, notably that on the Volfturno in October, 
1913, have been attributed to the spontaneous ignition 
of cargoes of this substance. Results of great interest 
will be looked for from the newly-erected rolling mill. 
Compared with last year’s abnormal figure, the 
number of models for private firms tested this year in 
the National Tank proves somewhat moderate. By 
NO. 2386, VOL. 95] 
NATURE 
[JULY 22.819n5 
suitable form modification, reductions of power at 
service speed, ranging to 13 per cent., were secured. 
Various researches were either continued or completed. 
In conjunction with that relating to fulness of form 
and longitudinal distribution, special study was made 
of the wave systems formed by the models. Further- 
more, attention was directed to the question of the 
similarity law suitable for strut-resistance. Unless 
suitably corrected, the resistance of a full-scale strut 
may, on the basis of measurements on a model, prove 
enormously over-estimated, 
That for a brief review numerous items of interest 
must pass unmentioned is inevitable. Sufficient, 
however, has been said to testify to the energy and 
success with which the work continues to be carried 
on despite adverse circumstances. It is to be hoped 
that, during the present emergency, every advantage 
will be taken of facilities which the laboratory can 
offer. Perfection and efficiency in all supplies of 
instruments and technical apparatus, with expedition 
in dealing with special questions, spell success to those 
fighting on sea and land. 

HEATING AND VENTILATING SYSTEMS. 
R. D. D. KIMBALL, the president of the 
American Society of Heating and Ven- 
tilating Engineers, and a member of the New 
York State Commission on Ventilation, has sent 
us two papers, one on the heating and ventilation 
of school buildings, and the other on church ventila- 
tion. He says that most of the failures of the past 
may be justly attributed to insufficient appropriations 
for the installation of ventilating systems and for 
their maintenance and operation. Very many installa- 
tions are incomplete, ill-designed, and installed with 
the use of unsuitable and cheap apparatus. Possibly 
the most frequent and serious cause of failure is the 
want of proper skill in operation. Plants are operated 
by boys or janitors who know absolutely nothing of 
the rudiments of fuel-burning, or care of a steam 
plant, or of a ventilating system. Often, too, there 
are such restrictions applied by the authorities that 
the proper operation of the plant is impossible. A 
school board, for example, directs that the plant 
must not be operated before or after certain dates, 
regardless of outside weather conditions, or offers 
a bonus to the janitor for saving coal, and yet 
directs that he must always operate nis fan engines. 
He removes the belt between engine and fan, and so 
secures his bonus. 
Mr. Kimball rightly insists on the heating and ven- 
tilation of schools being considered of the first import- 
ance in the estimates of any public building. Far too 
much is thought of the external appearance. The 
architecture should be adapted to the perfection of 
the physiological needs of the occupants, and the 
heating and ventilating engineers should be of equal 
authority with, not subservient to, the architect. A 
plan is given of the Wm. H. McKelvey School, of 
Pittsburgh. The air is taken through windows intoa 
fresh-air chamber, from which it passes through tem- 
pering heaters, air-washers, and reheaters into a 
double plenum chamber. From there it is driven by a 
motor fan into ducts with connections from the upper, 
or hot air, chamber and the lower, or tempered air, 
chamber. An individual duct runs to the base of each 
vertical flue communicating with the class-rooms. 
The mixing and volume dampers for each room are 
placed in the plenum chamber, under control of the 
janitor. 
The chief advantage of this system is that the 
required volume and temperature demanded by each 
| individual room may be had. Two sides of a building 

