ON PAINTING WITH MILK. 



ject to be attained, if the procefs I offer fhall afford a colour 

 equally good as that which is obtained by following the 

 procefs for the refinous milk paint. 



We read at page 250 of the memoir to which I allude, 

 that the oil added to the mixture of flaked lime and fkimmed 

 milk is diflblved by the lime, and then forms a calcareous 

 foap. 

 I/ime, milk, and By carefully examining what partes in this operation, I 

 oil form a triple have thought I obferved that the lime does not feparate from 

 the cafeous part to combine with the oil ; but that the oil 

 which is added in the mixture forms a triple combination, 

 little foluble in fact, but perfectly drfmfible in water. We 

 know, on the contrary, that calcareous foap is infoluble and 

 quite immifcible in water ; and I have found that the addition 

 of fkimmed milk produces no change in thefe properties. I 

 have alfo remarked, that the triple combination does not take 

 place, but in the order defer ibed by Cadet-de-Vaux, for the 

 lime does not entirely combine with a mixture of oil and 

 fkimmed milk. In this cafe there is only a formation of cal- 

 careous foap, which remains in mafles fufpended at the furface 

 of the liquid. 

 Sour milk unfit Cadet-de-Vaux alfo announces, in page 243 of his me 

 for the pigment. mo [ rf that four milk is no longer proper for the compofition 

 of this colour. He obferves, that the ferous part of the milk 

 being converted by fermentation to the ftate of acetous acid, 

 may then form a kind of calcareous acetite, which, by its 

 deliquefcence, muft contribute to deftroy the colour in which 

 it is mixed. 

 The whey is of I have verified this fact, and I think that the ferous part 

 little utility in cannot be ufeful in the compoiition of paint, unlefs before 

 t er P ufefulin tna ^ P er i°d in which the acefcence fhall have converted the 

 xnany other ap- fugar of milk it contains into acetous acid. For in the former 

 plications. ca f e -j. ls cap^^ f giving folidity and brightnefs. But. 



when we confider that the fermentation which produces this 

 phenomenon takes place with much rapidity ; that in many 

 countries this ferous part is ufed in bleaching, in the prepara- 

 tion of fugar of ; ik, and for the feeding of animals, we 

 fhall be defirous of retrenching it from a procefs in which it is 

 fometimes uleful, but oftener noxious, in order to appropriate 

 it entirely to thefe feveral ufes. 



By 



