"So far, therefore, as we can draw safe conclusions from a single specimen, there has been no marked change of race in the human population of Switzerland during the periods above considered"

This quote by Charles Lyell recommends that the human population of Switzerland has actually not experienced any significant changes in its racial makeup over the period of time that he has actually studied. Lyell is suggesting that the population of Switzerland has actually stayed reasonably stable and has not experienced any significant shifts in its racial composition. This might be due to a range of elements, such as a lack of immigration or an absence of intermarriage between different racial groups. Lyell is likewise suggesting that this conclusion is based on a single specimen, implying that more research is required to draw more conclusive conclusions. This quote highlights the importance of additional research and the need to think about numerous sources of evidence when making conclusions about the racial makeup of a population.