These decisions relate to three great divisions,—health, salubrity, and industry. Under health are classed, among other things, the researches on the adulteration of food, on the vessels used in its preparation, on the precautions to be taken with respect to the vessels and utensils of copper, regard being had to the uses for which they are employed; the experiments on the adulteration of salts, on the adulteration of bread and of flour by different substances, on the poisonous substances employed to colour bonbons, liqueurs, &c.; the examination of the methods employed in preparing pork; the examination of the water used for drink; the adulteration of the flours of linseed and mustard; the use of meat of animals who had died of disease; the researches into the salubrity of dwellings. The head of salubrity comprises the anatomical theatres, their construction, the means of remedying the causes of the unhealthiness which these establishments present; the discharge of sulphurous waters from the public baths, the utility of street fountains, the inspection of barracks, and the sanitary measures to which they should be subject; the improvements to be made in the fires of the establishments which employ coals; the arrangements to be made for the deposit of filth in the rural districts; the purification of sewers; the supply of water for domestic and industrial purposes; the steps to be taken in exhumations; the examination of different contrivances to empty privies, the ameliorations to be introduced into this portion of service; the wholesomeness of the markets, the inspection of prisons. The reports which relate to industry principally treat of the construction of slaughter-houses; the condensation of the gas and vapours resulting from the refining of metals; the fabrication, preservation, and sale of fulminating and lucifer matches; the precautions to be taken in the construction of fulminating powder-mills, and in the manipulation of the substances employed there; the measures to be taken for the conveyance of the fulminate of mercury; the researches into the employment of bitumens, and the conditions to be prescribed to the makers; the making wax-candles; the conditions to be imposed on cat-gut factories; the researches on the fires of wash-houses, and on the necessity of decomposing the soapy water to prevent putrefaction; the sanitary measures applicable to white lead manufactories, and the researches on the diseases of the workmen; the propositions of classification for different trades, such as the silk-hat factories, the forges, the places for making and keeping ether; and the beating of carpets.
Thus health, salubrity, industry, offer to the “Conseil de Salubrité” a vast field of researches and investigations, and we may affirm that there is no question relating to these three great departments of the administration which they have not profoundly meditated, and in part resolved. If now we turn to other subjects we still find important labours which touch in several points on the different matters of which we have just spoken, but which have not, like them, a special and clearly-defined character: such are the reports on epidemics and small-pox; the measures to be taken to prevent or combat them; the epizooties that have prevailed at different epochs among several species of animals, and particularly among milking-cows; the sale of horses with glanders, and the regulations to which they should be subject, as well as other animals seized with contagious diseases; the measures to be taken against mad dogs, and the precautions in case of bites from these animals; the modelling, examination, and embalming of corpses; the aids to be afforded to the drowned and suffocated; the measures to be taken to ascertain the number of these accidents as well as of suicides; the compilation of a new nosographic table of the diseases which cause death; the measures to be taken to prevent fires in theatres, &c. &c.
Such is a general view of the subjects upon which the council has been called to give their opinions. It now remains to describe the circumstances which demanded them, and the results they have produced.
One of the objects which more especially engaged the care of the council was that of bread. It is the thing, it is true, which most directly interests the people. The quality of bread may be deteriorated by various ingredients, but no one could have foreseen that noxious substances would be employed with the view, ostensibly at least, of improving it. Nevertheless the correctional tribunal of Brussels was called upon some years since to try some bakers brought before it under a charge of selling bread adulterated with noxious substances. On the occasion of this trial the prefect of police inquired of the council if, as these bakers alleged in their defence, a small quantity of a substance which they called blue alum, put into the yeast, had the property of rendering the bread whiter and less heavy.
In order to give their opinion, the council first examined what was the substance called by the name of blue alum. Some designate by this name the sulphate of copper, but most people mean by blue alum the rock alum, (sulphate of alumina and potass,) because this salt in the lump has a bluish tinge, and, as with all the sulphates, the sulphate of which the base is alumina is the only one which bears the name of alum, it is to be presumed that it is this salt, or rock alum, which goes under the name of blue alum, and not the sulphate of copper which is known in commerce by the name of blue vitriol.
It had been long known that alum, by the action of heat equal to that of a baker’s oven, swells, increases in volume, and becomes a porous mass, light and very white, which is no longer alum, but a mixture of a great deal of insoluble sub-sulphate with a small quantity of alum, a substance astringent, and not poisonous. It is probable that this property, known to some bakers, determined them to add to bread made of certain flour a little of this alum, which, without being injurious to the health, really made the bread whiter, at the same time that the crust became brown at a less heat.
As to the employment of sulphate of copper (blue vitriol), it is only by a gross error that it could be supposed capable of making bread white. Nevertheless a baker of the town of Gand was prosecuted for putting this poisonous salt into his bread. The commission appointed to examine the bread not having been able to discover any trace of copper, mixed a kilogram of flour, to which was added twenty-four grains of sulphate of copper, and they affirmed that it was impossible to detect in the bread the least trace of the salt they had introduced.
After such an assertion it became interesting to make some researches on the subject. In consequence, the delegates of the council who were entrusted with the inquiry, had four loaves of a kilogram of flour made under their eyes: in one of these loaves was put twelve grains of sulphate of copper, in another eight grains, in a third four grains, and but two grains in the fourth. These loaves rose ill, and although the flour with which they were made produced bread very beautiful and white, the four loaves were so heavy as scarcely to present any cavities. The loaf No. 1 had a green disagreeable colour; the loaf No. 2 was in like manner green, but of a less deep colour than the preceding; No. 3 was also greenish; and No. 4, though colourless, could not support a comparison with the bread made from the same flour pure.
All these loaves were burnt separately in porcelain crucibles to complete ashes. Those of the loaf No. 1 were a beautiful azure blue; those of No. 2 a clearer sky-blue; those of No. 3 had a blue tint of a lighter hue; and those of No. 4 were so slightly coloured that it would have been impossible to infer that they contained copper. But all these ashes, when submitted to the action of sulphuric acid diluted with water, were dissolved, and when tested separately by hydrosulphuric acid, produced black precipitates of sulphuret of copper, which precipitates, tested separately in their turn by concentrated nitric acid, furnished each a quantity of nitrate of copper, equal, within a few fractions, to the sulphate added to each of the four loaves.
It results, therefore, from the preceding experiments which have been made with the greatest care,