BOTLS AND HEALTHY. 543 
‘The great majority of pathologists now consider the infectious, 
and most of the contagious, diseases to be dependent on these low 
forms of life; and the tendency is, to consider that certain diseases or 
groups of diseases are produced only by specific forms of bacteria. 
These organisms are wide-spread, especially the various forms 
‘that ‘are associated with putrefaction and mould. Only on high 
‘mountains, and far from land on the ocean, is the air practically free 
from ‘them. Elsewhere the’ air, water, and soil teem with them. 
Their abundance ‘is’ necessarily’: pr dportionate to the amount of 
‘decomposing ‘organic matter in the neighbourhood, since they are 
or apie aH ting te on — the ‘processes of decomposition 
ao. | 
- Few ab, to realize what, an important part the soil plays in our 
tives, The water we drink (unless from cisterns) has leached through 
‘The air we breathe is frequently loaded with its dust. It is 
our food. The soil is highly porous; and the interstices between the 
Bramelaxe filled withowaternor with airne—hgnolind-water’ orf ground- 
vair.3¢ DHégrotindsnin diuctmabteslwithithinxdrying ‘bayomatric: pressure, 
-eatdwviblyothessfisé anda fallcefhthdigrouidavatieri in rainy: andudry 
(Heagdnsod he ‘ground-water! flows! aecording-tathe.common davisiof 
abe an ee ive A at aM Sie aaa iuod tig He et Ut slowly 
hic ashe neat’ io ges iF Bh i ie water is 
cee ans mae é‘butts gaye | tibw. of the fact 
Ne aa ne at ag atten in ‘arresting 
eae fy, Clear S18 adootd hot-sveswee vd poaaes WRIT OTK 
iltering througlthem. ; Dio T3 4 larsox to wol .a9ag9 eG 
“at femeht 'rék th ae ng “unsterilized water through one 
ne 
AY shit’ § QOH AS’ Of “Sterilized |  beetitntutl ion, and Hat whole 
ne avmovéementaétardédobyi frretionti a2 ota toqsy 
of dur. ‘ho yses are ih tid or ess Close 
. it a ee of} it i "i as ‘thoug kent to 
Faces ti ich” was. ri out, for 
cme a aan j Ak ‘assist ted "h Te aa 
oiight!bit ey dled tn z 
arriead. pia finer than. very: scoarse! clsine ave! iionisios 2aiedn- 
| tinuous eapacity, forrwtesting!. thd jae of bactaia fron» cae air 
bei Se ou porae dw find, “a attest ‘and 161d 9 PRR hie 
ores of Bactérie’ c ‘patton ed i iater:' The: experiment’ on which this 
He ie féet ee pipe ‘neal ith gant Which! ‘had “been ‘sterilized 
— "HO" a Pa Seal This" p pipe was’ “connected” by ‘an air- 
spe iste ‘for Several! weeks * eford use. The’ ‘frat ‘dro ie ‘Of water 
that" eee meesaeH Hes hubaved Feb? of “sand: infecpet the beef. 
infusion, causing it to putrefy. 
| BOD Pst dither Baek i i ei Sp ee ne detach: {iSriselves 
tr oii’ ste id Gr teii's we ha ato the air except through 
Ten ton bf? i aeae Bio a ray, 0 on throu agh: thie fo forthation of 
bet: vporpitiont que ‘tro 2 Moss 
to ae apy oy ja odd at oometagt staompott ga edt ia sidae 100 
syd De }-ehief; opractioal sinferences}.fromothese atiesultsoare; ‘thet 
distannes, exenol,bundteds of; feats between wells ditid eesspools;are 
ne xpretection against: infection, and) that,a.dry fou (ianialternately wet 
end day, cellan may be\moreidangerons:thanch pexthanchtly webonie: 
