London Labour and the London Poor, Vol. 2

by Henry Mayhew

1st. In a perfectly dry state, so that the particles no longer exist either in a state of cohesion or aggregation, but are minutely divided and distinct, it is known by the name of “dust.”

2nd. When in combination with a small quantity of water, so that it assumes the consistency of a pap, the particles being neither free to move nor yet able to resist pressure, the detritus is known by the name of “mac mud,” or simply “mud,” according as it proceeds from a macadamized or stone paved road.

3rd. When in combination with a greater quantity of water, so that it is rendered almost liquid, it is known as “slop-dirt.”

4th. When in combination with a still greater quantity of water, so that it is capable of running off into the sewers, it is known by the name of “street surface-water.”

The mud of the streets of London is then merely the dust or detritus of the granite of which they are composed, agglutinated either with rain or the water from the watering-carts. Granite consists of silex, felspar, and mica. Silex is sand, while felspar and mica are also silex in combination with alumina (clay), and either potash or magnesia. Hence it would appear to be owing to the affinity of the alumina or clay for moisture, as well as the property of silex to “gelatinize” with water under certain conditions, that the particles of dry dust derive their property of agglutinating, when wetted, and so forming what is termed “mud”—either “mac,” or simple mud, according, as I said before, to the nature of the paving on which it is formed.

By dust the street-cleansers mean the collection of every kind of refuse in the dust-bins; but I here speak, of course, of the fine particles of earthy matter produced by the attrition of our roads when in a dry state. Street-dust is, more properly speaking, mud deprived of its moisture by evaporation. Miss Landon (L. E. L.) used to describe the London dust as “mud in high spirits,” and perhaps no figure of speech could convey a better notion of its character.

In some parts of the suburbs on windy days London is a perfect dust-mill, and although the dust may be allayed by the agency of the water-carts (by which means it is again converted into “mac,” or mud), it is not often thoroughly allayed, and is a source of considerable loss, labour, and annoyance. Street-dust is not collected for any useful purpose, so that as there is no return to be balanced against its prejudicial effects it remains only to calculate the quantity of it annually produced, and thus to arrive at the extent of the mischief.

Street-dust is disintegrated granite, that is, pulverized quartz and felspar, felspar being principally composed of alumina or clay, and quartz silex or sand; it is the result of the attrition, or in a word it is the detritus, of the stones used in pavements and in macadamization; it is further composed of the pulverization of all horse and cattle-dung, and of the almost imperceptible, but still, I am assured, existent powder which arises from the friction of the wooden pavement even when kept moist. In the roads of the nearest suburbs, even around such places as the Regent’s-park, at many seasons this dust is produced largely, so that very often an open window for the enjoyment of fresh air is one for the intrusion of fresh dust. This may be less the case in the busier and more frequently-watered thoroughfares, but even there the annoyance is great.

I find in the “Reports” in which this subject is mentioned but little said concerning the influence of dust upon the public health. Dr. Arnott, however, is very explicit on the subject. “It is,” says he, “scarcely conceivable that the immense quantities of granite dust, pounded by one or two hundred thousand pairs of wheels (!) working on macadamized streets, should not greatly injure the public health. In houses bordering such streets or roads it is found that, notwithstanding the practice of watering, the furniture is often covered with dust, even more than once in the day, so that writing on it with the finger becomes legible, and the lungs and air tubes of the inhabitants, with a moist lining to detain the dust, are constantly pumping in the same atmosphere. The passengers by a stage-coach in dry weather, when the wind is moving with them so as to keep them enveloped in the cloud of dust raised by the horses’ feet and the wheels of the coach, have their clothes soon saturated to whiteness, and their lungs are charged in a corresponding degree. A gentleman who rode only 20 miles in this way had afterwards to cough and expectorate for ten days to clear his chest again.”