- It gives us the measure of the man to know that the thought uppermost in the mind of Mackenzie returning from the Arctic was not pride in the deed accomplished but a realization of his limitations in astronomical knowledge. - "The New North", Agnes Deans Cameron.
- His uncle next sent him to Leipzig to study law, but he managed to continue his astronomical researches. - "Kepler", Walter W. Bryant.
- The Romans on this occasion penetrated further than even Agricola had gone, and reached Cape Wrath, where Severus made careful astronomical observations. - "Early Britain--Roman Britain", Edward Conybeare.