For some time past an animated discussion has been going on in the columns of the “Comptes Rendus de l'Académie des Sciences” between MM. Dubranfaut and Maumené regarding the nature of inverted sugar. M. Dubranfaut, many years ago, made many valuable additions to our knowledge concerning the composition and reactions of various sugars, especially in explaining the result of the action of dilute acids on cane sugar. He explained the levo-rotatory action of inverted sugar, and its rapidly varying power with the temperature, as the result of a molecule of water in reacting with a molecule of cane sugar, generating one molecule of glucose and one of lævulose. Dubranfaut believed that inverted sugar consisted of a mixture of glucose and lævulose in equal weights; and although he did not make a direct analysis of the product, yet he was justly entitled to assume that it was so constituted, seeing that, generally, it agreed with a mean of the properties of inulin sugar and dextrose.