anchor.diff:  
   /datum/gas_mixture/immutable/share(datum/gas_mixture/sharer, atmos_adjacent_turfs = 4)
   	. = ..(sharer, 0)
  -	reset_gas_mix()
  +	garbage_collect()
   
   /datum/gas_mixture/immutable/after_share()
  -	temperature = initial_temperature
  -	reset_gas_mix()
  +	garbage_collect()
   
   /datum/gas_mixture/immutable/react()
   	return 0 //we're immutable.
  
positive.code: /datum/gas_mixture/immutable/cloner
  	initial_temperature = T20C
  
  /datum/gas_mixture/immutable/cloner/reset_gas_mix()
  	assert_gas("n2")
  	gases["n2"][MOLES] = MOLES_O2STANDARD + MOLES_N2STANDARD
  	..()
  
  /datum/gas_mixture/immutable/cloner/heat_capacity()
  	return (MOLES_O2STANDARD + MOLES_N2STANDARD)*20 //specific heat of nitrogen is 20
  
negative.code: /datum/gas_mixture/immutable
  	var/initial_temperature
  
  /datum/gas_mixture/immutable/New()
  	..()
  	garbage_collect()
  
  /datum/gas_mixture/immutable/garbage_collect()
  	temperature = initial_temperature
  	temperature_archived = initial_temperature
  	gases.Cut()
  
  /datum/gas_mixture/immutable/archive()
  	return 1 //nothing changes, so we do nothing and the archive is successful
  