Scientific American Supplement, No. 384, May 12, 1883

V >> Various >> Scientific American Supplement, No. 384, May 12, 1883

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At this stage of the works, namely, in the fall of 1881 the structure
presented somewhat the appearance of a bridge with short spans. The
whole river--fortunately low--flowed through the sluices of which there
were 113 and also through a bulkhead which had been left alongside
of the slide with a water width of 60 ft. These openings had a total
sectional area of 4,400 sq. ft., and barely allowed the river to pass,
although, of course, somewhat assisted by leakage.

[Illustration: Fig. 1. CROSS SECTION IN DEEP WATER.]

It now only remained, to complete the dam, to close the openings. This
was done in a manner that can be readily understood by reference to
the cuts. Gates had been constructed with timber 10 in. thick, bolted
together. They were hung on strong wooden hinges and, before being
closed, laid back on the face of dam as shown at B, Figs. 1, 2, and 3.
They were all closed in a short time on the afternoon of 9th November,
1881. To do this it was simply necessary to turn them over, when the
strong current through the sluices carried them into their places, as
shown at A, Figs. 2 and 3 and by the dotted lines on Fig. 1. The closing
was a delicate as well as dangerous operation, but was as successfully
done as could be expected. No accident happened further than the
displacement of two or three of the gates. The openings thus left
were afterward filled up with timber and brushwood. The large opening
alongside of the slide was filled up by a crib built above and floated
into place.

The design contemplates the filling up with stone and gravel on
up-stream side of dam about the triangular space that would be formed by
the production of the line of face of flat dam till it struck the rock.
Part of that was done from the ice last winter; the balance is being put
in this winter.

Observations last summer showed that the calculations as to the raising
of the surface of the river were correct. When the depth on the crest
was 2.50 feet, the water at the foot of the Longue Sault was found to be
25 in. higher than if no dam existed. The intention was to raise it 24
in.

The timber slide was formed by binding parallel piers about 600 feet
long up and down stream, as shown on the map, and 28 ft. apart, with a
timber bottom, the top of which at upper end is 3 ft. below the crest
of dam. It has the necessary stop logs, with machinery to move them, to
control the water. The approach is formed by detached piers, connected
by guide booms, extending about half a mile up stream. See map.

Alongside of the south side of the slide a large bulkhead was built, 69
ft. wide, with a clear waterway of 60 ft. It was furnished with stop
logs and machinery to handle them. When not further required, it was
filled up by a crib as before mentioned.

The following table shows the materials used in the dam and slide, and
the cost:

______________________________________________________________________
| | | Stone | Exca- | |
| Timber, | Iron, | filling, | vation, | Cost. |
| cu. ft. | lb. | cu. yds. | cu. yds.| |
+---------+---------+----------+---------+----------+
Temporary works | 134,500 | 92,000 | 11,400 | | $79,000 |
| | | | | |
Permanent dam | 265,000 | 439,600 | 24,000 | 6,500 | 151,000 |
| | | | | |
Slide, including | 296,500 | 156,400 | 32,800 | | 102,000 |
apparatus | | | | | |
+---------+---------+----------+---------+----------+
| | | | | |
Total | 696,000 | 687,000 | 68,200 | 6,500 | $332,000 |
-----------------+---------+---------+----------+---------+----------+

The above does not include cost of surveys, engineering, or
superintendence, which amounted to about ten per cent, of the above sum.

[Illustration: DETAILS OF THE OTTAWA RIVER DAM, AT CARILLON.]

The construction of the dam and slide was ably superintended by Horace
Merrill, Esq., late superintendent of the "Ottawa River Improvements,"
who has built nearly all the slides and other works on the Ottawa to
facilitate the passage of its immense timber productions.

The contractors were the well known firm of F.B. McNamee & Co., of
Montreal, and the successful completion of the work was in a large
degree due to the energy displayed by the working member of that
firm--Mr. A.G. Nish, formerly engineer of the Montreal harbor.

THE CANAL

The canal was formed by "fencing in" a portion of the river-bed by an
embankment built about a hundred feet out from the north shore and
deepening the intervening space where necessary. There are two
locks--one placed a little above the foot of the rapid (see map), and
the other at the end of the dam. Wooden piers are built at the upper and
lower ends--the former being 800 ft. long, and the latter 300 ft; both
are about 29 ft. high and 35 ft. wide.

The embankment is built, as shown by the cross section, Fig. 6. On the
canal side of it there is a wall of rubble masonry F, laid in hydraulic
cement, connecting the two locks, and backed by a puddle wall, E, three
feet thick; next the river there is crib work, G, from ten to twenty
feet wide and the space between brick-work and puddle filled with earth.
The outer slope is protected with riprap, composed of large bowlders.
This had to be made very strong to prevent the destruction of the bank
by the immense masses of moving ice in spring.

The distance between the locks is 3,300 feet.

In building the embankment the crib-work was first put in and followed
by a part (in width) of the earth-bank. From that to the shore temporary
cross-dams were built at convenient distances apart and the space pumped
out by sections, when the necessary excavation was done, and the walls
and embankments completed. The earth was put down in layers of not more
than a foot deep at a time, so that the bank, when completed, was solid.
The water at site of it varied in depth from 15 feet at lower end to 2
feet at upper.

The locks are 200 ft. long in the clear between the gates, and 45 ft
wide in the chamber at the bottom. The walls of the lower one are 29 ft.
high, and of the upper one 31 ft They are from 10 to 12 ft thick at the
bottom,

The locks are built similar to those on the new Lachine and Welland
canals, of the very best cut stone masonry, laid in hydraulic cement.
The gates are 24 in. thick, made of solid timber, somewhat similar to
those in use on the St. Lawrence canals. They are suspended from anchors
at the hollow quoins, and work very easily. The miter sills are made of
26 in. square oak. The bottom of the lower lock iis timbered throughout,
but the upper one only at the recesses, the rock there being good.

[Illustration: MAP OF THE OTTAWA RIVER AT CARILLON RAPIDS.

SECTION OF RIVER AT DAM. NOTE.--THE LOWEST DOTTED LINE IS LOW WATER
BEFORETHE DAM WAS BUILT. THEN THE LINE OF HIGH WATER WAS ABOUT A FOOT
ABOVE WHAT IS CREST OF DAM NOW.]

The rise to be overcome by the two locks is 16 ft., but except in medium
water, is not equally distributed. In high water nearly the whole lift
is on the upper lock, and in low water the lower one. In the very lowest
known stage of the river there will never be less than 9 ft. on the
miter sills.

As mentioned at the beginning of this article, four locks were required
on the old military canal to accomplish what is now done by two.

The canal was opened in May, 1882, and has been a great success, the
only drawback--although slight--being that in high water the current for
about three-quarters of a mile above the upper pier, and at what was
formerly the Chute a Biondeau, is rather strong. These difficulties can
be easily overcome--the former by building an embankment from the pier
to Brophy's Island, the latter by removing some of the natural dam of
rock which once formed the "Chute."

The following are, in round numbers, the quantities of the principal
materials used:

Earth and puddle in embankment ...cub. yds. 148,500
Rock excavation, " 38,000
Riprap, " 6,600
Lock masonry " 14,200
Rubble masonry, " 16,600
Timber in cribs, lock bottoms and gates " 368,000
Wrought and cast iron, lb ................. 173,000
Stone filling cu yds ...................... 45,300
Concrete " 830

The total cost to date has been about $570,000, not including surveys,
engineering, etc.

The contractors for the canal, locks, etc., were Messrs. R. P. Cooke &
Co., of Brockville, Ont., who have built some large works in the States,
and who are now engaged building other extensive works for the Canadian
Government. The work here reflects great credit on their skill.

On the enlarged Grenville Canal, now approaching completion, there
are five locks, taking the place of the seven small ones built by the
Imperial Government. It will be open for navigation all through in the
spring of 1884, when steamers somewhat larger than the largest now
navigating the St. Lawrence between Montreal and Hamilton can pass up to
Ottawa City.--_Engineering News_.

* * * * *

DWELLING HOUSES--HINTS ON BUILDING--"HOME, SWEET HOME."

[Footnote: From a paper read before the Birmingham Architectural
Association, Jan 30, 1883]

By WILLIAM HENMAN, A.R.I.B.A.

My intention is to bring to your notice some of the many causes which
result in unhealthy dwellings, particularly those of the middle classes
of society. The same defects, it is true, are to be found in the palace
and the mansion, and also in the artisan's cottage; but in the former
cost is not so much a matter of consideration, and in the latter, the
requirements and appliances being less, the evils are minimized. It is
in the houses of the middle classes, I mean those of a rental at from
L50 to L150 per annum, that the evils of careless building and want
of sanitary precautions become most apparent. Until recently sanitary
science was but little studied, and many things were done a few years
since which even the self-interest of a speculative builder would not do
nowadays, nor would be permitted to do by the local sanitary authority.
Yet houses built in those times are still inhabited, and in many cases
sickness and even death are the result. But it is with shame I must
confess that, notwithstanding the advance which sanitary science has
made, and the excellent appliances to be obtained, many a house is now
built, not only by the speculative builder, but designed by professed
architects, and in spite of sanitary authorities and their by-laws,
which, in important particulars are far from perfect, are unhealthy, and
cannot be truly called sweet homes.

Architects and builders have much to contend with. The perverseness of
man and the powers of nature at times appear to combine for the express
purpose of frustrating their endeavors to attain sanitary perfection.
Successfully to combat these opposing forces, two things are above all
necessary, viz 1, a more perfect insight into the laws of nature, and a
judicious use of serviceable appliances on the part of the architect;
and, 2, greater knowledge, care, and trustworthiness on the part of
workmen employed. With the first there will be less of that blind
following of what has been done before by others, and by the latter the
architect who has carefully thought out the details of his sanitary work
will be enabled to have his ideas carried out in an intelligent manner.
Several cases have come under my notice, where, by reckless carelessness
or dense ignorance on the part of workmen, dwellings which might have
been sweet and comfortable if the architect's ideas and instructions had
been carried out, were in course of time proved to be in an unsanitary
condition. The defects, having been covered up out sight, were only made
known in some cases after illness or death had attacked members of the
household.

In order that we may have thoroughly sweet homes, we must consider the
localities in which they are to be situated, and the soil on which they
are to rest. It is an admitted fact that certain localities are more
generally healthy than others, yet circumstances often beyond their
control compel men to live in those less healthy. Something may, in
the course of time, be done to improve such districts by planting,
subdrainage, and the like. Then, as regards the soil; our earth has
been in existence many an age, generation after generation has come and
passed away, leaving behind accumulations of matter on its surface, both
animal and vegetable, and although natural causes are ever at the work
of purification, there is no doubt such accumulations are in many cases
highly injurious to health, not only in a general way, but particularly
if around, and worse still, under our dwellings. However healthy a
district is considered to be, it is never safe to leave the top soil
inclosed within the walls of our houses; and in many cases the subsoil
should be covered with a layer of cement concrete, and at times with
asphalt on the concrete. For if the subsoil be damp, moisture will rise;
if it be porous, offensive matter may percolate through. It is my belief
that much of the cold dampness felt in so many houses is caused by
moisture rising from the ground inclosed _within_ the outer walls.
Cellars are in many cases abominations. Up the cellar steps is a
favorite means of entrance for sickness and death. Light and air, which
are so essential for health and life, are shut out. If cellars are
necessary, they should be constructed with damp proof walls and floors;
light should be freely admitted; every part must be well ventilated,
and, above all, no drain of any description should be taken in. If they
be constructed so that water cannot find its way through either walls or
floors, where is the necessity of a drain? Surely the floors can be
kept clean by the use of so small an amount of water that it would be
ridiculous specially to provide a drain.

The next important but oft neglected precaution is to have a good damp
course over the _whole_ of the walls, internal as well as external. I
know that for the sake of saving a few pounds (most likely that they may
be frittered away in senseless, showy features) it often happens, that
if even a damp course is provided in the outer walls, it is dispensed
with in the interior walls. This can only be done with impunity on
really dry ground, but in too many cases damp finds its way up, and, to
say the least, disfigures the walls. Here I would pause to ask: What is
the primary reason for building houses? I would answer that, in this
country at least, it is in order to protect ourselves from wind and
weather. After going to great expense and trouble to exclude cold and
wet by means of walls and roofs, should we not take as much pains to
prevent them using from below and attacking us in a more insidious
manner? Various materials may be used as damp courses. Glazed
earthenware perforated slabs are perhaps the best, when expense is no
object. I generally employ a course of slates, breaking joint with a
good bed of cement above and below; it answers well, and is not very
expensive. If the ground is irregular, a layer of asphalt is more easily
applied. Gas tar and sand are sometimes used, but it deteriorates and
cannot be depended upon for any length of time. The damp course should
invariably be placed _above_ the level of the ground around the
building, and _below_ the ground floor joists. If a basement story is
necessary, the outer walls below the ground should be either built
hollow, or coated externally with some substance through which wet
cannot penetrate. Above the damp course, the walls of our houses must
be constructed of materials which will keep out wind and weather. Very
porous materials should be avoided, because, even if the wet does not
actually find its way through, so much is absorbed during rainy weather
that in the process of drying much cold is produced by evaporation. The
fact should be constantly remembered, viz., that evaporation causes
cold. It can easily be proved by dropping a little ether upon the bulb
of a thermometer, when it will be seen how quickly the mercury falls,
and the same effect takes place in a less degree by the evaporation of
water. Seeing, then, that evaporation from so small a surface can
lower temperature so many degrees, consider what must be the effect of
evaporation from the extensive surfaces of walls inclosing our houses.
This experiment (thermometer with bulb inclosed in linen) enables me as
well to illustrate that curious law of nature which necessitates the
introduction of a damp course in the walls of our buildings; it is known
as capillary or molecular attraction, and breaks through that more
powerful law of gravitation, which in a general way compels fluids to
find their own level. You will notice that the piece of linen over the
bulb of the thermometer, having been first moistened, continues moist,
although only its lower end is in water, the latter being drawn up by
capillary attraction; or we have here an illustration more to the point:
a brick which simply stands with its lower end in water, and you can
plainly see how the damp has risen.

From these illustrations you will see how necessary it is that the brick
and stone used for outer walls should be as far as possible impervious
to wet; but more than that, it is necessary the jointing should be
non-absorbent, and the less porous the stone or brick, the better able
must the jointing be to keep out wet, for this reason, that when rain is
beating against a wall, it either runs down or becomes absorbed. If both
brick and mortar, or stone and mortar be porous, it becomes absorbed; if
all are non-porous, it runs down until it finds a projection, and then
drops off; but if the brick or stone is non-porous, and the mortar
porous, the wet runs down the brick or stone until it arrives at the
joint, and is then sucked inward. It being almost impossible to obtain
materials quite waterproof, suitable for external walls, other means
must be employed for keeping our homes dry and comfortable. Well built
hollow walls are good. Stone walls, unless very thick, should be lined
with brick, a cavity being left between. A material called Hygeian Rock
Building Composition has lately been introduced, which will, I believe,
be found of great utility, and, if properly applied, should insure a dry
house. A cavity of one-half an inch is left between the outer and inner
portion of the wall, whether of brick or stone, which, as the building
rises, is run in with the material made liquid by heat; and not only is
the wall waterproofed thereby, but also greatly strengthened. It may
also be used as a damp course.

Good, dry walls are of little use without good roofs, and for a
comfortable house the roofs should not only be watertight and
weathertight, but also, if I may use the term, heat-tight. There can be
no doubt that many houses are cold and chilly, in consequence of the
rapid radiation of heat through the thin roofs, if not through thin and
badly constructed walls. Under both tiles and slates, but particularly
under the latter, there should be some non-conducting substance, such
as boarding, or felt, or pugging. Then, in cold weather heat will be
retained; in hot weather it will be excluded. Roofs should be of a
suitable pitch, so that neither rain nor snow can find its way in in
windy weather. Great care must be taken in laying gutters and flats.
With them it is important that the boarding should be well laid in
narrow widths, and in the direction of the fall; otherwise the boards
cockle and form ridges and furrows in which wet will rest, and in time
decay the metal.

After having secured a sound waterproof roof, proper provision must be
made for conveying therefrom the water which of necessity falls on it in
the form of rain. All eaves spouting should be of ample size, and the
rain water down pipes should be placed at frequent intervals and of
suitable diameter. The outlets from the eaves spouting should not be
contracted, although it is advisable to cover them with a wire grating
to prevent their becoming choked with dead leaves, otherwise the water
will overflow and probably find its way through the walls. All joints
to the eaves spouting, and particularly to the rain-water down pipes,
should be made watertight, or there is great danger, when they are
connected with the soil drains, that sewer gas will escape at the joints
and find its way into the house at windows and doors. There should be a
siphon trap at the bottom of each down pipe, unless it is employed as a
ventilator to the drains, and then the greatest care should be exercised
to insure perfect jointings, and that the outlet be well above all
windows. Eaves spouting and rain-water down pipes should be periodically
examined and cleaned out. They ought to be painted inside as well as
out, or else they will quickly decay, and if of iron they will rust,
flake off, and become stopped.

It is impossible to have a sweet home where there is continual dampness.
By its presence chemical action and decay are set up in many substances
which would remain in a quiescent state so long as they continued dry.
Wood will rot; so will wall papers, the paste used in hanging them,
and the size in distemper, however good they have been in the first
instance; then it is that injurious exhalations are thrown off, and the
evil is doubtless very greatly increased if the materials are bad in
themselves. Quickly grown and sappy timber, sour paste, stale size, and
wall papers containing injurious pigments are more easily attacked, and
far more likely to fill the house with bad smells and a subtile poison.
Plaster to ceilings and walls is quickly damaged by wet, and if improper
materials, such as road drift, be used in its composition, it may become
most unsavory and injurious to health. The materials for plaster cannot
be too carefully selected, for if organic matter be present, the result
is the formation of nitrates and the like, which combine with lime and
produce deliquescent salts, viz, those which attract moisture. Then,
however impervious to wet the walls, etc., may be, signs of dampness
will be noticed wherever there is a humid atmosphere, and similar evils
will result as if wet had penetrated from the exterior. Organic matter
coming into contact with plaster, and even the exhalations from human
beings and animals, will in time produce similar effects. Hence stables,
water closets, and rooms which are frequently crowded with people,
unless always properly ventilated, will show signs of dampness and
deterioration of the plaster work; wall paper will become detached from
the walls, paint will blister and peel off, and distemper will lose its
virtue. To avoid similar mishaps, sea sand, or sand containing salt,
should never be used either for plaster or mortar. In fact, it is
necessary that the materials for mortar should be as free from salts and
organic matter as those used for plaster, because the injurious effects
of their presence will be quickly communicated to the latter.

Unfortunately, it is not alone by taking precaution against the
possibility of having a damp house that we necessarily insure a "sweet
home." The watchful care of the architect is required from the cutting
of the first sod until the finishing touches are put on the house. He
must assure himself that all is done, and nothing left undone which is
likely to cause a nuisance, or worse still, jeopardize the health of
the occupiers. Yet, with all his care and the employment of the best
materials and apparatus at his command, complete success seems scarcely
possible of attainment. We have all much to learn, many things must
be accomplished and difficulties overcome, ere we can "rest and be
thankful."

It is impossible for the architect to attempt to solve all the problems
which surround this question. He must in many cases employ such
materials and such apparatus as can be obtained; nevertheless, it is his
duty carefully to test the value of such materials and apparatus as
may be obtainable, and by his experience and scientific knowledge to
determine which are best to be used under varying circumstances.

But to pass on to other matters which mar the sweetness of home. With
many, I hold that the method usually employed for warming our dwellings
is wasteful, dirty, and often injurious to health. The open fire,
although cheerful in appearance, is justly condemned. It is wasteful,
because so small a percentage of the value of the fuel employed is
utilized. It is dirty, because of the dust and soot which result
therefrom. It is unhealthy, because of the cold draughts which in its
simplest form are produced, and the stifling atmosphere which pervades
the house when the products of imperfect combustion insist, as they
often do, in not ascending the flues constructed for the express purpose
of carrying them off; and even when they take the desired course, they
blacken and poison the external atmosphere with their presence. Some of
the grates known as ventilating grates dispose of one of the evils of
the ordinary open fire, by reducing the amount of cold draught caused by
the rush of air up the flues. This is effected, as you probably know, by
admitting air direct from the outside of the house to the back of the
grate, where it is warmed, and then flows into the rooms to supply the
place of that which is drawn up the chimneys. Provided such grates act
properly and are well put together, so that there is no possibility of
smoke being drawn into the fresh air channels, and that the air to
be warmed is drawn from a pure source, they may be used with much
advantage; although by them we must not suppose perfection has been
attained. The utilization of a far greater percentage of heat and the
consumption of all smoke must be aimed at. It is a question if such can
be accomplished by means of an open fire, and it is a difficult matter
to devise a method suited in every respect to the warming of our
dwellings, which at the same time is equally cheering in appearance.
So long as we are obliged to employ coal in its crude form for heating
purposes, and are content with the waste and dirt of the open fire, we
must be thankful for the cheer it gives in many a home where there are
well constructed grates and flues, and make the best use we can of the
undoubted ventilating power it possesses.

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