I have read with interest Colin Jack-Hinton's article ‘The Use of Apparent Consistency in Errors of Latitude in the Identification of 16th and 17th Century Pacific Islands Discoveries’ in the July 1964 issue of the Journal of the Institute of Navigation (pp. 311–13). Jack-Hinton takes as his main target the two instances in my book The Discovery of the Pacific Islands in which I used persistent or steady southerly error as an aid to or basis for differentiations between atolls situated north and south of each other, namely Mendaña's Los Bajos de la Candellaria in reference to Roncador Reef and Ontong Java, and the first atoll seen by Le Maire after leaving the Home Islands in relation to Ontong Java and Nukumanu.