[PLUG] sort option for 'natural' sequence

[Rich Shepard]

sample.dat:

'648',17,'2011-07-11','Insecta','Plecoptera','Chloroperlidae''Suwallia'
'652',17,'2011-07-11','Insecta','Plecoptera','Pteronarcidae''Pteronarcella'
'895',17,'2010-09-13','Insecta','Ephemeroptera','Baetidae''Baetis'
'899',17,'2010-09-13','Insecta','Diptera','Psychodidae''Pericoma'
'901',17,'2010-09-13','Insecta','Coleoptera','Hydrophilidae''Cymbiodyta'
'907',17,'2010-09-13','Insecta','Trichoptera','Glossosomatidae''Glossosoma'
'909',17,'2010-09-13','Insecta','Diptera','Chironomidae''Cladotanytarsus'
'914',17,'2010-09-13','Insecta','Plecoptera','Nemouridae''Zapada'
'918',17,'2010-09-13','Insecta','Trichoptera','Hydropsychidae''Hydropsyche'
'919',17,'2010-09-13','Insecta','Coleoptera','Dytiscidae''Hydroporus'
'920',17,'2010-09-13','Insecta','Trichoptera','Lepidostomatidae''Lepidostoma'
'922',17,'2010-09-13','Insecta','Coleoptera','Elmidae''Narpus'
'1120',17,'2006-06-27','Insecta','Diptera','Chironomidae''Polypedilum'
'134',41,'2004-06-07','Insecta','Plecoptera','Nemouridae''Amphinemura'
'135',3,'2004-06-07','Insecta','Ephemeroptera','Baetidae''Baetus'
'137',41,'2004-06-07','Insecta','Ephemeroptera','Baetidae''Baetis'
'138',3,'2004-06-07','Insecta','Coleoptera','Hydrophilidae''Berosus'
'139',3,'2004-06-07','Insecta','Plecoptera','Chloroperlidae''Sweltsa'
'141',41,'2004-06-07','Insecta','Plecoptera','Chloroperlidae''Suwallia'
'145',3,'2004-06-07','Insecta','Diptera','Simulidae''Prosimulium'
'148',3,'2004-06-07','Annelida','Oligochaeta','Lumbricidae''Ilyodrilus/Tubifex'
'151',3,'2006-06-15','Insecta','Diptera','Chironomidae''Eukiefferiella'
'154',41,'2004-06-07','Insecta','Coleoptera','Dytiscidae''Hydrovatus'
'155',3,'2004-06-07','Insecta','Coleoptera','Dytiscidae''Hydrovatus'
'216',SC,'2005-07-13','Insecta','Diptera','Ephydridae'''
'1126',17,'2006-06-27','Insecta','Ephemeroptera','Baetidae''Baetis'
'1128',17,'2006-06-27','Insecta','Trichoptera','Brachycentridae''Brachycentrus'
'1129',17,'2006-06-27','Insecta','Diptera','Chironomidae''Tvetenia'
'2060',11,'2012-07-11','Insecta','Coleoptera','Elmidae''Narpus'
'2061',11,'2012-07-11','Insecta','Diptera','Chironomidae''Natarsia'
'2062',11,'2012-07-11','Insecta','Trichoptera','Hydroptilidae''Ochrotrichia'
'8',11,'2000-07-18','Insecta','Ephemeroptera','Leptophlebiidae''Paraleptophlebia'
'11',11,'2000-07-18','Insecta','Trichoptera','Glossosomatidae''Agapetus'
'12',11,'2000-07-18','Insecta','Diptera','Tipulidae''Tipula'
'592',17,'2011-07-11','Annelida','Oligochaeta','Tubificidae'''

I've tried the various sort options (-g, -h, -n, -k) and they all sort
character-by-character which puts the line beginning with '8' between '652'
and '895'. I know how to do this for cidr addresses but I've no local
reference that works for only the first field.

Clue wanted,

Rich