When our friends left I at once followed them in the hopes of marking down their invisible attendant. So wily was he that he had not trusted himself upon foot, but he had availed himself of a cab so that he could loiter behind or dash past them and so escape their notice.
Al marcharse nuestros amigos los seguí al instante con la esperanza de localizar a su invisible acompañante, pero nuestro hombre ha tenido la precaución de no trasladarse a pie sino utilizar un coche, lo que le permitía rezagarse o adelantarlos a toda velocidad y escapar así a su detección.