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7. Speaking of macadamised roadways, Mr. H. Percy Boulnais (now City Engin- eer of Liverpool) in his book on Municipal Engineering, says: "Telford's object was the complete separation of the road mictal from the subsoil by a firm and regular foundation, and this system has ever since held its ground."
The advantages to be gained by constructing a roadway in this manner may be summed up as follows:-
(1) Economy of construction, as a considerable quantity of metalling is saved.
(2) The prevention of the rising up or "spewing" of the clay or other soft
material on which the roadway rests.
(3) A solid foundation is secured which will successfully resist the weight
and precussions of the traffic.
(4) The increased facility for the drainage of the roadway, water being
ruinous to it.
No. 3 of the above advantages helps to explain why it is that, with a proper foundation hard stone can be used advantageously, as, having a good support, the traffic is enabled to wear the surface evenly.
8. In connection with the subject herein treated, the following statement by Mr. Boulnais is interesting. The great objections to macadamised roadways, are as
follows:-
*
(1) They manufacture too much mud and dust.
(2) They are too absorbent.
(3) They are very noisy, and damaging to vehicles.
(4) They constantly require mending but never scein quite sound.
(5) They are frequently encumbered by men and carts engaged in either re-
pairs, cleansing or watering.
(6) They are very expensive to maintain and cleanse.
I would call special attention to No. 2 of the above. Sanitarians are now agreed that in centres of population it is most desirable to have the thoroughfares non-absorbent.
9. Turning now to wood paving, its principal advantages, may be stated as follows :-
(1) It is the quietest of all known pavements.
(2) It is much safer than either asphaltic or granite paving for horses travel-
ling upon it.
(3) It offers very little resistance to traction.
(4) It is very clean.
(5) Absorbes very little moisture.
(6) It is inexpensive to maintain. Its chief disadvantage is that it is not easy to open for the purpose of laying gas and water pipes etc., and it has to be left a little time after repairs before traffic is again allowed upon it.
This difficulty might, however, largely be met by a notice in the Gazette that parties wishing to lay gas pipes etc., in certain roads could do so before a certain date, as the roadway would not be allowed to be opened afterwards except for a very special purpose.
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