A construction is given which
yields to any quasi-metrizable not non-archimedeanly quasi-metrizable space
another quasi-metrizable space which is not σ-orthocompact. It is shown that
(σ-)orthocompactness does not imply non-archimedean quasi-metrizability and is
neither summable nor multiplicative nor (CH) hereditary in completely regular
quasi-metric spaces.
It is proved that quasi-metric spaces are preserved under perfect
mappings.