▁could . ▁He ▁continued ▁collect ing ▁min er als ▁and ▁insect s , ▁and ▁family ▁hol id ays ▁in ▁Wales ▁brought ▁Charles ▁new ▁opportun ities , ▁but ▁an ▁older ▁sister ▁ruled ▁that ▁" it ▁was ▁not ▁right ▁to ▁kill ▁insect s " ▁for ▁his ▁collections , ▁and ▁he ▁had ▁to ▁find ▁dead ▁ones . ▁He ▁read ▁Gilbert ▁White ' s ▁The ▁Natural ▁History ▁and ▁Anti qu ities ▁of ▁Sel bor ne ▁and ▁took ▁up ▁bird watch ing . ▁Er as ▁took ▁an ▁interest ▁in ▁chem istry ▁and ▁Charles ▁became ▁his ▁assistant , ▁with ▁the ▁two ▁using ▁a ▁garden ▁shed ▁at ▁their ▁home ▁fitted ▁out ▁as ▁a ▁labor atory ▁and ▁extending ▁their ▁interests ▁to ▁cry stal log raph y . ▁When ▁Er as ▁went ▁on ▁to ▁a ▁medical ▁course ▁at ▁the ▁University ▁of ▁Cambridge , ▁Charles ▁continued ▁to ▁r ush ▁home ▁to ▁the ▁shed ▁on ▁week ends , ▁and ▁for ▁this ▁received ▁the ▁nick name ▁" G as ". ▁The ▁head master ▁was ▁not ▁am used ▁at ▁this ▁di version ▁from ▁studying ▁the ▁class ics , ▁calling ▁him ▁a ▁poc oc ur ante ▁( tr if ler ) ▁in ▁front ▁of ▁the ▁boys . ▁At ▁fifteen , ▁his ▁interest ▁shift ed ▁to ▁hunting ▁and ▁bird - sh oot ing ▁at ▁local ▁est ates , ▁particularly ▁at ▁Ma er ▁in ▁Staff ord shire , ▁the ▁home ▁of ▁his ▁relatives , ▁the ▁Wed g wood s . ▁His ▁ex as per ated ▁father ▁once ▁told ▁him ▁off , ▁saying ▁" You ▁care ▁for ▁nothing ▁but ▁shooting