Animals were exposed in a cage similar to that used in the inhalation experiments previously described, but, instead of blowing in the contaminated air, the cages were so arranged that boards freshly painted with the special paint under experiment were introduced into the cage daily, the animals remaining the whole time in the chamber. Special precautions were taken with regard to ventilation. 2. An animal was placed in a chamber, and the compound to be tested was heated electrically by means of a coil surrounding the glass tube in which the compound was placed. The current was regulated by means of resistances, so that the thermo-couple and galvanometer gave a constant reading of 59° C. Air was constantly passed through the tube over the heated substance and into the animal’s cage, which was efficiently ventilated. In this way any emanations which were given off from the normal room temperature or up to 59° C. were carried over into the animal’s cage, and there breathed. The apparatus was so arranged that the heating coil extended close to the point of delivery into the cage. The result of these experiments showed that the animals confined in cages and exposed to freshly painted surfaces, where the paint used was white lead, zinc oxide, or lead sulphate, very soon showed signs of poisoning, and they became emaciated and suffered from recurrent attacks of salivation. The animals exposed in the cages in which air was passed over either white lead paste, zinc paste, or lead sulphate paste, showed no signs of illness, although kept in the cage and subjected to the inhalation of any fumes which might be given off for three months, spending the whole of the day in the cage, but being removed during the night to separate cages. It therefore seemed clear that, whatever illness was produced in the animals exposed to fresh paint, they were not suffering from absorption of lead, but of some other compound of which the paint was made. Various constituents of the paint were therefore tried--namely, the metallic bases, lead or zinc, and linseed-oil, with turpentine and lead acetate mixed with turpentine. The animal exposed to the turpentine alone very rapidly showed signs of disease--salivation, a tendency to diarrhœa, strabismus, but the latter only after a two-hour exposure, whilst the quantity of turpentine present in the cage air did not exceed 10 milligrammes per litre.