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acter, lightness and elegance. But while I have seen
much of this high class work, and executed some,
the
ever-present regret one feels in the colony is that so little
of it is in demand. The country is probably too young,
and feels itself bound to be content with humbler things
until it can afford better. But of one thing I do com-
plain : it is the
system of tendering for every
kind of
work. Every contractor is assumed to be equally able to
do artistic work; cheapness is held to be the criterion of
merit and not quality. Things are different in England.
A man of merit there is treated with respect, and his
worth is acknowledged. I suppose things will improve
here as we develop a richer and more leisured class. As
this class grows, so the appreciation for art work of every
description will grow
with it—aconsummation devoutly
to be wished ! —From Canadian Architect.
ILLUMINATING BUILDING INTERIORS.
ARTIFICIAL
illumination of the interior of buildings
is a subject that has engrossed the attention of ar-
chitects for many years, we may say
from time imme-
morial. Their efforts have been taxed to the utmost in
late
years, as civilization has become more refined and
the demand for more light to illuminate artistic inte-
riors has grown. When the electric light made it appear-
ance it marked a new era in lighting, in that a demand
was created in a new direction for beautiful illuminating
effects. Artists exercised their knowledge and skill to
the utmost limit, and the success which has attended
their efforts is familiar to most every one who has a pair
of good eyes in his head.
The Journal of the Royal Institute of British Architects
in a recent number published an abstract of a paper on
the subject of internal illumination of buildings, read
before that body by Mr. W. H. Preece, the eminent Eng-
lish electrician.
As this abstract contains a good deal that is of interest,
we publish it in full for the benefit of our readers:

The art of internal illumination of buildings, the
author considers, is just born, and will be an art in the
future. Electricity is rendering theatres bearable and
houses healthier, while the architect is brought face to
face with a new art, in which the aid of the electrician is
required to solve some of the difficulties. History is si-
lent as to the origin of tallow, pitch, wax and oil, but
gas as an illuminant came in with the present century.
From the earliest days, history, whether culled from
paintings or writings, teaches that lights have been dim
and crude until the middle of the present century.
Light, by whatever means generated, follows the same
laws, and is due to the rapid rhythmic undulation of the
medium, called the ether, that fills all
space.
Wherever
there is light there is heat, and the hope of the philoso-
pher to supply light without any heat at all is at present
but a dream. Light cannot be produced without heat,
and the higher the temperature the brighter the light.
Color varies with the rate of vibration of the ether, while
changes of color are due to the changes of wave-motion
of the ether. Light may become so intense that all
sense of color is lost, and every bright illumination
causes all colors to appear whitish. If light emanates
from a point its intensity diminishes with the square of
the distance. The candle is the British standard source
of light, and the bright surface produced by it at a dis-
tance of one foot the standard illumination by which to
measure the amount of light distributed by any other
means. This standard Mr. Preece calls a ‘lux.’ A six-
teen candle-power glow lamp is a lamp which gives a
light equal to that of sixteen British standard candles
concentrated on one spot, and it will at a distance of
four feet
give the illumination of a lux. Thus one can-
dle-power at one foot, four candles at two feet, nine can-
dles at three feet, sixteen candles at four feet, twenty-five
candles at five feet, give exactly the same illumination,
viz
,
one lux, on the paper on which we write or on the
page
from which we read. The
great problem is to dif-
fuse light throughout a room so that it be distributed
uniformly over the working surfaces with an intensity of
a lux. Sixteen-candle glow lamps suspended eight feet
above the floor, and fixed in eight-feet squares,
effect
this very well; and
groups
of four such lamps fixed six-
teen feet high produce a similar result. The light a
lamp gives is owing to the expenditure of energy in its
carbon filament; an electric current is driven through
this filament by electric
pressure,
its resistance is over-
come, it is intensely heated by the proceeding, and the
result is
pure
unadulterated light. The energy ex-
pended per second by an ampere (the standard
current),
driven by a volt (the standard pressure), is called a watt.
A sixteen-candle glow lamp takes sixty-four watts,
which, assuming the lamps to be fixed eight feet high,
means that one watt per square foot of surface is required
to secure ample illumination from lamps so fixed.
Therefore, in designing the normal illumination of
rooms, Mr. Preece takes the floor area in
square
feet and
divides it by sixty-four, which gives the number of six-
teen candle-power lamps required, fixed eight feet high ;
these being increased or diminished according to the
purposes of the
room,
its form and height, etc. The
adaptability of the
eye to nearly every degree of light is
very great, and it is almost impossible for it to judge ac-
curately of the amount of light present; but it is not as
a mere source of light that the glow lamp is
superior to
the gas
burner. The former can be
put anywhere and
used without the adventitious aid of match or fire. It
does not vitiate nor unnecessarily warm the air, and it
simplifies the problem of ventilation, while it lends it-
self above all to the aesthetic harmony of furniture and
decorations. Electric light is not always absolutely safe;
security is to be obtained only by good design, perfect
materials, first-class workmanship and rigid inspection.
Imperfect materials erected by cheap contractors lead to
many disasters; on the other hand, it is stated no fire
has occurred in buildings fitted
up
under the rules and
regulations, and inspected by the officers of the insurance
companies in this country. Mr. Preece advocates keep-
ing everything as much as possible in
view, and not hid-
ing the conductors under wainscots or floors or above
ceilings. The glow lamps excited by three watts per
candle is at present the most perfect source of domestic
light, and when patent expires—in a year or two —will
be obtainable at one-third the
present price. It is
scarcely fair, Mr. Preece thinks, to say
all light should
come from the side of a room, as Lord Beaconsfield
stated in
£
Lotliair’ when describing the lighting of Bel-
mont. The House of Commons is one of the best
lighted
chambers in London, and is lighted from the roof, a
false glass ceiling excluding the heat and glare, and ad-
mitting only the light. What is wanted is to avoid the
glare of the incandescent filament in the eyes, and to
prevent the lamp from being too obtrusive; it can be
shaded from the
eye
without its effectiveness being de-
stroyed, and without the flow of light being obstructed
or its quality being deteriorated.
Judging from the
Costal Palace Exhibition, at which several leading firms
239
THE SOUTHERN ARCHITECT.

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