▁in ▁danger ▁of ▁ex communic ation . ▁ ▁Spain ▁promised ▁to ▁send ▁him ▁ 5 0 0 ▁rein for c ements ▁to ▁decis ively ▁end ▁the ▁war , ▁but ▁only ▁ 3 0 0 ▁arrived . ▁In ▁addition , ▁this ▁smaller ▁force ▁was ▁of ▁much ▁less er ▁quality ▁than ▁hoped ▁and ▁was ▁almost ▁completely ▁without ▁equipment . ▁Over coming ▁these ▁difficulties ▁and ▁his ▁sick ness ▁( he ▁had ▁to ▁be ▁carried ▁by ▁chair ▁to ▁the ▁battle field ), ▁Qu iro ga ▁launched ▁a ▁new ▁off ensive ▁against ▁the ▁Map uch es , ▁this ▁time ▁led ▁by ▁their ▁to qui ▁the ▁mest izo ▁Al onso ▁Dí az . ▁ ▁The ▁campaign ▁had ▁relative ▁success , ▁which ▁allowed ▁Qu iro ga ▁to ▁confront ▁another ▁men ace , ▁the ▁appearance ▁of ▁Sir ▁Francis ▁Dra ke ▁off ▁the ▁Chile an ▁coast s . ▁Dra ke ▁managed ▁to ▁s ack ▁the ▁port ▁of ▁Val para í so , ▁but ▁when ▁he ▁tried ▁to ▁repeat ▁the ▁action ▁at ▁La ▁Ser ena , ▁he ▁encountered ▁the ▁armed ▁resistance ▁of ▁the ▁inhabitants , ▁and ▁was ▁rep uls ed . ▁ ▁Val div ia ▁earth qu ake ▁ ▁On ▁December ▁ 1 6 , ▁ 1 5 7 5 ▁an ▁earth qu ake ▁struck ▁southern ▁Chile , ▁and ▁ru ined ▁the ▁cities ▁of ▁La ▁Imperial , ▁Vill arr ica , ▁Os orno , ▁Castro , ▁and ▁spe cially ▁the ▁city ▁of ▁Val div ia , ▁where ▁the ▁qu ake ▁caused ▁a ▁lands lide ▁that ▁plug ged ▁the ▁d rain age ▁of ▁Lake