Besides these questions which relate to the quality of the bread, the council examined what mischief could arise from the use of copper scales to weigh the dough of which the bread is made. It is known that the dishes of these scales are copper, and that instead of being cleaned with cloths they are cleaned with the chains by which they are suspended, and which, for this purpose, are heaped together and act like a brush. This state of things seriously engaged the attention of the council with respect to the danger it presents. The dough, composed of water and flour, and containing in addition a certain quantity of marine salt, sticks to the dishes of the scales, and exercises on the metal a chemical action, of which the result is the oxide of copper. The oxide, or salts of copper, which is formed, next penetrates into the portion of the dough which is afterwards detached by the friction of the chains.
We may suppose that in this case some of the oxide of copper would be introduced into the bread, and that it is important for the public health to take measures to prevent, from negligence or imprudence, bread which contained even very small quantities of salts of copper, from being offered for consumption. The council thought that all danger would be prevented.
1. By compelling the bakers to use no scales but those of which the dishes were of tinned iron.
2. In prescribing to them to clean the dishes of the scales by means of chains of tinned iron, which should only be used for this purpose.
3. By obliging them to wash the chains, and the pan in which they are kept, with warm water.
4. By prohibiting the bakers to employ in their bakehouses utensils of zinc, or red and yellow copper.
5. By ordering the bakers, if it is not found expedient to impose the execution of the measures indicated in the first and third articles, to tin substantially the chains and dishes of their scales, and any utensils of zinc, or red and yellow copper.
The council have been occupied at different periods with the adulterations of salt, and they have not ceased to lend active assistance to the measures of surveillance prescribed by the Government. Unhappily its efforts were long unsuccessful. Even now the analysis which has been made of more than 6000 samples of salt, proves that fraud always exists, although of a kind less detrimental to the public health. In 1829 the council proposed to forbid the sale of salt which contained from five to six per cent. of salts with a potash base, and to oppose, in addition, the sale of salt mixed with sea-weed, even in small quantities. The council has since renewed their investigations. More than 3000 samples of salt, taken from the shops, were analysed by M. Chevalier, who discovered that 309 samples were adulterated by ground plaster, or salts of potash, or sulphate of soda, or by the iodines. These adulterations were found chiefly in the grey salts. The later experiments of the council have confirmed these results. They have, moreover, shown that the salt derived from the mines of the south is more pure than the salt of the west. It contains less water, and less of the insoluble matter foreign to sea-salt.
We wish we could follow the council in their numerous observations on the filtering of water—on the use of vessels and utensils of copper—on the dangers they present according to the circumstances in which they are employed—and on the regulations of which they ought to be the object; but there still remains much to be extracted, to show their solicitude for everything which concerns the well-being of the people, and the preservation of the public health.
The council, in an article entitled, “Necessity to submit the Construction of Houses to Sanitary Rules,” inserted in its General Report for 1827 (p. 39), expressed the wish to see established in the centre of every quarter of the town a spacious square, railed in, and planted with trees, in which the children of all classes might, without, apprehension, and without the special superintendence of their parents, give themselves up to the exercise suitable to their years, and in which the inhabitants of all ages might enjoy the solar influence, and breathe a purer air than in their dwellings. It is, they said, so much the more needful to come to this determination, that nearly all the gardens have given place to houses, to streets, or to passages, and that the greater part of those which have been preserved are surrounded by houses so lofty that vegetation languishes for want of air and light, which renders their existence more hurtful than beneficial to health. To these reasons, which have lost nothing of their force, we will add that which results from the advantages the quarter would receive from the presence of such squares in respect to the healthiness produced by favouring the ventilation of the streets; because a square is to all the streets which open into it a true fourneau d’appel with a double current, acting by night as well as by day, at the same time that it is a powerful means by which to facilitate the action of the winds in the interior of the town.