CHAPTER VIII

THEOBALD SMITH

TICKS AND TEXAS FEVER

I

It was Theobald Smith who made mankind turn a corner. He was the

first, and remains the captain of American microbe hunters. He poked

his nose--following the reasoning of some plain farmers--around a

sharp turn and came upon amazing things; and now this history tells

what Smith saw and what the trail-breakers who came after him found.

“It is in the power of man to make parasitic maladies disappear from

the face of the globe!” So promised Pasteur, palsied but famous

after his fight with the sicknesses of silkworms. He promised

that, you remember, with a kind of enthusiastic vehemence, making

folks think they might be rid of plagues by a year after next at

the latest. Men began to hope and wait.... They cheered as Pasteur

invented vaccines--marvelous these were but not what you would call

microbe-exterminators. Then Koch came, to astound men by his perilous

science of finding the tubercle bacillus, and, though Koch promised

little, men remembered Pasteur’s prophecy and waited for consumption

to vanish.... Years went by while Roux and Behring battled bloodily

to scotch the poison of diphtheria; mothers crooned hopeful songs

into the ears of their children.... Some men giggled, but secretly

hoped a little too, that the mighty (albeit windy) Metchnikoff might

teach his phagocytes to eat up every germ in the world.... Diseases

were getting a bit milder maybe--the reason is still mysterious--but

they seemed in no hurry to vanish, and men had to keep on waiting....

Then arose a young man, Theobald Smith, at the opening of the last

ten years of the eighteen hundreds, to show why northern cows get

sick and die of Texas fever when they go south, and to explain why

southern cows, though healthy, go north and trail along with them a

mysterious death for northern cattle. In 1893 Theobald Smith wrote

his straight, clear report of the answer to this riddle; there was

certainly no public horn-tooting about it and the report is now out

of print--but that report gave an idea to the swashbuckling David

Bruce; it gave hints to Patrick Manson; it set thoughts flickering

through the head of the brilliant but indignant Italian, Grassi; that

report gave confidence in his dangerous quest to the American Walter

Reed and that gang of officers and gallant privates who refused extra

pay for the job of being martyrs to research.

What kind of man is this Theobald Smith (safe to say all but a few

thousand Americans have never even heard of him), and how could his

discoveries about a cow disease set such dreams stirring--how could

those farmers’ reasonings that he proved, show microbe hunters a way

to begin to realize the poetic promise of Pasteur to men?

II

In 1884 Theobald Smith was in his middle twenties; he was a Bachelor

of Philosophy of Cornell University; he was a doctor of medicine

from the Albany Medical College. But he detested the idea of going

through life solemnly diagnosing sicknesses he could not hope to

cure, offering sympathy where help was needed, trying to heal

patients for whom there was no hope--in brief, medicine seemed to

him to be a mixed-up, illogical business. He was all for biting into

the unknown in places where there was a chance of swallowing it--a

little of it--without having mental indigestion. In short, though a

physician, he wanted to do science! In especial he was eager--as what

searcher was not in those piping days--about microbes. At Cornell

(it was before the days of jazz) he had played psalms and Beethoven

on the pipe organ; here too (college activities had not yet engulfed

mere learning) Theobald Smith dug thoroughly into mathematics,

into physical science, into German, and particularly he became

enthusiastic about looking through microscopes. Maybe then he saw his

first microbe....

But when he came to the medical school at Albany, he found no

excitement about possibly dastardly bacilli among the doctors of the

faculty; germs had not yet been set up as targets for the healing

shots of the medical profession; there was no course in bacteriology

there--nor, for that matter, in any medical school in America.

But he wanted to do science! And, caring nothing for the healthy

drunkennesses and scientific obscenities of the ordinary medical

student, Theobald Smith soothed himself with the microscopic study of

the interiors of cats. In his first published paper he made certain

shrewd observations on peculiar twists of anatomy in the depths of

the bellies of cats--that was his bow as a searcher.

He graduated and wanted above everything to be an experimenter, but

he had, before anything, to make a living. Just then young American

doctors were hurrying to Europe, eager to look over Koch’s shoulder

to learn ways to paint bacilli, to breed them true, to shoot them

under the skins of animals, and to talk like real experts about

them. Theobald Smith would have liked to go but he had to find a

job. And presently, while those other well-off young Americans were

getting in on the ground floor of the new exciting science (afterward

they told how they had actually worked in the same room with those

great Germans!) and when they were getting ready to land important

professorships, Theobald Smith got his job. A humble and surely

not academically respectable job it was too! For he was appointed

one of the staff of the then feeble, struggling, insignificant,

financially rather ill-nourished, and in general almost negligible

Bureau of Animal Industry at Washington. Counting Smith, there were

four members of the staff of this Bureau. The Chief was a good man

named Salmon. He was enthusiastically interested in what germs might

do to cows and sincerely passionate about the importance of bacilli

to pigs--but he knew nothing of how to find the microbes harassing

these valuable creatures. Then there was Mr. Kilborne who rejoiced in

the degree of Bachelor of Agriculture and was something of a horse

doctor (he now runs a hardware store in New York, up-state). And

finally, this staff to which Smith came, was glorified by the ancient

and redoubtable Alexander, a darky ex-slave who sat about solemnly,

and when urged, got up to wash the dirty bottles or chaperon the

guinea-pigs.

In a little room lighted by a dormer window under the roof in the

attic of a government building, Smith set out to hunt microbes. It

was his proper business! Naturally he went at it, as if he had been

born with a syringe in his hand and a platinum wire in his mouth.

Though a university graduate, he read German well, and of nights,

with gulps, he gobbled up the brave doings of Robert Koch; like a

young duck taking to the water he began to imitate Koch’s subtle ways

of nursing and waylaying hideous bacilli and those strange spirilla

who swim about like living corkscrews.... “I owe everything to Robert

Koch!” he said, and thought of that far-off genius as some country

baseball slugger might think of Babe Ruth.

In his dingy attic he was tireless. It made no difference that he

was not strong--all day and part of the night he hunted microbes.

And he had musician’s fingers that helped him to brew microbe soups

with very few spillings. In off moments he would swat the regiments

of cockroaches who marched without stopping into his attic from

the lumber room close by. In a remarkably short time he had taught

himself everything needful and began to make cautious discoveries--he

invented a queer new safe kind of vaccine, which contained no bacilli

but only their filtered formless protein stuff. The heat of his attic

was an intensification of the shimmering hell Washington knows how to

be, but he wiped the sweat from the end of his nose and set to work

in the right, classic way of Koch--with an astounding instinct he

avoided the cruder methods of Pasteur.

III

You talk about freedom of science! You think a free choice to dig

in any part of the Unknown is needed by searchers? I used to think

so, and I have got into trouble with eminent authorities for saying

so--too loudly. Wrong! For Theobald Smith, with little more freedom

to start with than some low government clerk--had to research into

things Dr. Salmon told him to research at, and Dr. Salmon was paid to

direct Smith to solve puzzles which were bothering the farmers and

stock-raisers. Such was science in the Bureau of Animal Industry. Dr.

Salmon and Bachelor Kilborne and Theobald Smith--to say nothing of

the indispensable Alexander--were expected to rush out like firemen

and squirt science on the flaming epidemics threatening the pigs and

heifers and bulls and rams of the farmers of the land. Just then the

stock-raisers were seriously upset by a very weird disease, the Texas

fever.

Southern cattlemen bought northern cattle; they were unloaded from

their box-cars and put to graze on the fields along with perfectly

healthy southern cows; everything would go well for a month or

so, and then, bang! an epidemic burst out among northern cows.

They stopped eating, they lost dozens of pounds a day, their urine

ran strangely red, they stood aimless with arched backs and sad

eyes--and in a few days every last one of the fine northern herd lay

stiff-legged on the field. The same thing happened when southern

steers and heifers were shipped North; they were put into northern

fields, grazed there awhile, were driven away perhaps; when northern

cows were turned into those fields where their southern sisters had

been, in thirty days or so they began to die--in ten days after that

a whole fine herd might be under the ground.

What was this strange death, brought from the South by cattle

never sick with it themselves, and left invisibly in ambush on the

fields? Why did it take more than a month for those fields to become

dangerous? Why were they only dangerous in the hot summer months?

The whole country was excited about it; there was bad feeling between

the meridional cowmen and their colleagues of the North; New York

City went into a panic when carloads of stock shipped East for beef

began to die in hundreds on the trains. Something must be done! And

the distinguished doctors of the Metropolitan Health Board went to

work to try to find the microbe cause of the disease....

Meanwhile certain wise old Western cattle growers had a theory--it

was just what you would call a plain hunch got from smoking their

pipes over disastrous losses of cows--they had a notion that Texas

fever was caused by an insect living on the cattle and sucking blood;

this bug they called a _tick_.

The learned doctors of the Metropolitan Board and all of the

distinguished horse doctors of the various state Experiment Stations

laughed. Ticks cause disease! Any insect cause disease! It was

unheard of. It was against all science. It was silly! “... A little

thought should have satisfied any one of the absurdity of this

idea,” pronounced the noted authority, Gamgee. This man was up to

his nose in the study of Texas fever, and never mentioned a tick;

the scientists all over gravely cut up the carcasses of cows and

discovered bacilli there (but never saw a tick). “It is the dung

spreads it!” said one. “You are wrong, it is the saliva!” said

another. There were as many theories as there were scientists. And

the cattle kept on dying.

IV

Then, in 1888, Dr. Salmon put Theobald Smith, with Kilborne to help

him, and Alexander to clean up after them--saying nothing about ticks,

Salmon put his entire staff to work on Texas fever. “Discover the

germ!” he told Smith. That year they had nothing but the spleens and

livers of four dead Texas fever cows to investigate; packed in pails

of ice, from Virginia and Maryland to his furnace-like attic came

those livers and spleens. Theobald Smith had what so many of those

mystified scientists and baffled horse doctors lacked--horse sense.

He turned his microscope on to different bits of the first sample of

spleen; he spied microbes in it; there was a veritable menagerie of

different species of them.

Then Smith sniffed at that bit of spleen. He wrinkled up his nose--it

smelled. It was spoiled.

At once he sent out messages, asking the stockmen to get the insides

out of their cattle right away after they died, to pack them quickly

in ice, to see they got to the laboratory more quickly. It was done,

and in the next spleen he found no microbes at all--but only a great

quantity of mysteriously broken up red corpuscles of the blood. “They

look wrecked!” he said. But he could find no microbes. He was still

young, and sarcastic, and impatient with any searcher who couldn’t

do close hard thinking. A man named Billings had claimed a foolish

common bacillus (which he found in every part of every dead cow and

in every corner of the barnyard--including the manure pile--as well)

was the cause of Texas fever. Billings wrote a spread-eagle paper,

saying: “The sun of original research, in disease, seems to be rising

in the West instead of the East!”

“Somewhat pompous claims,” said Smith, and he blew away all that

pseudo-scientific rubbish in a few dry sentences. Smith knew it was

no good sitting in a laboratory, with no matter how many guinea-pigs

and what an array of fine syringes, simply to peer at the spleens

and livers of more or less odoriferous cows. He was an experimenter;

he must study the living disease; be there while the cows kicked

their last quivering spasms; he must follow nature. He began to get

ready for the summer of 1889, when, one day, Kilborne told him of the

cattlemen’s ridiculous theory about the ticks.

In a moment he pricked up his mental ears. “The farmers, the ones who

lose the stock, who see most of Texas fever, they think that?”

Now, though Theobald Smith was born in a city, he liked the smell

of hay just cut and the brown furrows of fresh-turned fields. There

was something sage--something as near as you can come to _truth_ for

him in a farmer’s clipped sentences about the crops or the weather.

Smith was learned in the marvelous shorthand of mathematics; men

of the soil don’t know that stuff. He was absolutely at home among

the scopes and tubes and charts of shining laboratories--in short,

this young searcher was full of sophisticated wisdom that laughs

at common sayings, that often jeers at peasant platitudes. But in

spite of all of his learning (and this was an arbitrary strange

thing about him!) Theobald Smith did not confuse fine buildings and

complicated apparatus with clear thinking--he seemed always to be

distrusting what he got out of books or what he saw in tubes.... He

felt the dumbest yokel to be profoundly right when that fellow took

his corn-cob pipe from his maybe unbrushed teeth to growl that April

showers brought May flowers.

He listened to Kilborne’s gossip about that idiotic theory of ticks;

Kilborne told him the cattlemen of the West were pretty well agreed

it was ticks. Well, pondered Smith, those fellows were surely

innocent of any fancy reasoning to corrupt their brains, they reeked

of the smell of steers and heifers, they were almost, you might say,

a part of their animals; and they were the ones who had to lay awake

nights knowing this dreadful disease was turning their cattle’s blood

to water, to taking the bread from their children’s mouths. They had

to bury those poor wasted beasts. And these experienced farmers one

and all said: “No ticks--no Texas fever!”

Theobald Smith would follow the farmers. He would watch the disease

as nearly as possible as those stockmen had watched it. Here was a

new kind of microbe hunting--following nature, and changing her by

just the smallest tricks.... The summer of 1889 came, the days grew

hot; the year before the cattlemen had complained bitterly about

their losses. It was urgent to do something, even the government

saw that. The Department of Agriculture loosened up with a good

appropriation, and Dr. Salmon, the Director, directed that the work

begin--luckily he knew so little about experiments that his direction

never bothered Smith in the slightest.

V

With Kilborne, Theobald Smith now built an outlandish laboratory, not

between four walls but under the hot sky, and the rooms of that place

of science were nothing more than five or six little dusty fenced off

fields. On June 27 of 1889, seven rather thin but perfectly healthy

cows came off a little boat which brought them from farms in North

Carolina, from the heart of the Texas fever country, where it was

death for northern cattle to go. And these seven cows were, one and

all of them, decorated, infested and plagued by several thousands of

ticks, assorted sizes of them, some so tiny they needed a magnifying

glass to be seen--and then there were splendid female ticks half an

inch long, puffed up with blood sucked from their long-suffering

hosts.

Into securely fenced Field No. 1, Smith and Kilborne drove four of

these tick-loaded southern cattle, and with them they put six healthy

northern beasts----“Pretty soon the northerners will be getting the

ticks on them too, they have never been near Texas fever.... They are

susceptible, and then...?” said Smith. “And now for a little trick to

see if it is the ticks we have to blame!”

So Theobald Smith did his first little trick--call it an experiment

if you wish--it was a stunt a shrewd cattleman might have thought

of if he hadn’t been too busy to try it; it was an experiment all

other American scientists considered it silly to attempt. Smith and

Kilborne set out to pick off, with their hands, every single tick

from the remaining three southern cattle! The beasts kicked and

switched their tails in these strange experimenters’ faces; it was

way over a hundred in the sun, and the dust from the rampaging of the

offended cows hung in clouds around them and stuck to their sweaty

foreheads. Buried away under the matted hair of the cattle hid those

ticks, and the little ones out in the open seemed to crawl away under

the hair when the cramped fingers of the searchers went after them.

And how those damned parasites stuck to their cow-hosts--there were

magnificent blood-gorged lady ticks who mashed up into nasty messes

when you tried to pull them off--it was a miserable business!

But toward evening of that day they could find never a tick on any

of those three North Carolina cows, and into Field No. 2 they put

them, along with four healthy northern beasts. “These northerners,

perfectly fit for a fatal attack of Texas fever, will be rubbing

noses with the southerners, will be nibbling the same grass,

drinking from the same water, sniffing at the North Carolina cow’s

excretions--but they’ll get no ticks from them. Well--now to wait and

see if it’s the ticks who are to blame!”

July and the first of August were two months of hot but strenuous

waiting. Smith, with a Government bug-expert named Cooper Curtice,

kept himself busy with vast studies of the lives and works and ways

of ticks. They discovered how a six-legged baby tick climbs up onto a

cow, how it fastens itself to the cow’s hide, begins to suck blood,

sheds its skin, proudly acquires two more legs, sheds its skin again;

they found out the eight-legged females then marry (on the cow’s

back) each of them a little male, how the lady-ticks then have great

feasts of blood, grow to tick womanhood--and at last drop off the cow

to the ground to lay their two thousand or more eggs; so, hardly more

than twenty days after their journey up the leg of the cow, their

mission in life is done, and they shrivel up and die--while strange

doings begin in each of those two thousand eggs....

Meanwhile, every day--it was a relief to get out of that cockroachy

attic even to those burning fields--Theobald Smith journeyed out to

his open air laboratory where Kilborne the future hardware dealer

was in command. He went to Field No. 1 to see if ticks had got on

to any of the northern cattle yet, to see if they were getting hot,

if their heads drooped; he crossed over to Field No. 2 to pick a

few more ticks off those three North Carolina cows--a few new ones

always seemed to be popping up, grown from ones too small to see that

first day!--it was nervous business, making sure those three cows

stayed clean of ticks.... It was, to tell the truth, a perspiring and

not too interesting waiting until that day a little past the middle

of August, when the first northern cow began to show ticks, and

presently to stand with her back arched, refusing to eat. Then the

ticks appeared on all the northerners; they burned with fever, their

blood turned to water, their ribs stuck out and their flanks grew

bony--and ticks? They seemed to be alive with ticks!

But on Field No. 2, where there were no ticks, the northern cows

stayed as healthy as their North Carolina mates....

Each day the fever of the northern beasts in Field No. 1 went

higher--then one by one they died; the barns ran red with the

blood of the post mortems, and there were rushings to and fro

between the dead beasts on the field and the microscopes in the

attic--even Alexander, dimly sensing the momentous things afoot,

even Alexander got busy. And Theobald Smith looked at the thin blood

of the dead cows. “It is the blood the unknown Texas fever microbe

attacks--something seems to get into the blood corpuscles of the

cows and burst them open--it is _inside_ the blood cells I must look

for the germ,” pondered Smith. Now, though he distrusted the reports

of alleged microscope experts, he was nevertheless himself mighty

sharp with this machine. He turned his most powerful lens onto the

blood of the first cow that died, and--here was luck!--in the very

first specimen he spied queer little punched-out pear-shaped spaces

in the otherwise solid discs of the blood corpuscles. At first they

simply looked like holes, but he focussed up and down, and fussed,

and looked at a dozen thin bits of glass with blood between them.

Presently these spaces began to turn into queer pear-shaped living

creatures for him. In the blood of every beast dead of Texas fever he

found them--always inside the corpuscles, wrecking the corpuscles,

turning the blood to water. Never did he find them in the blood of a

healthy northern cow.... “It may be the microbe of Texas fever,” he

whispered, but like a good peasant he did not jump to conclusions--he

must look at the blood of a hundred cows, sick and healthy, he must

examine millions of red blood cells to be sure....

By now the hottest weather had passed, it was September, and in

Field No. 2, the northern cattle, all four of them, kept on grazing

and grew fat--there were no ticks there. And Smith muttered: “We’ll

see if it’s the ticks who are to blame!” and he took two of these

unharmed northern beasts and led them into Field No. 1, where so many

beasts had died--in a week a few of the little red-brown bugs were

crawling up these new cow’s legs. In a little more than two weeks one

of these cows was dead, and the other sick, of Texas fever.

But there never was a man who needed more experiences to convince him

of something he wanted to believe. He must be sure! And there was

still another simple trick he could try--call it an experiment if you

wish. From North Carolina, from the fatal fields down there, came

large cans and these cans were filled with grass, that swarmed with

ticks, crawling, thirsty for the blood of cows. These cans Theobald

Smith took on to Field No. 3, where no southern cattle or their

blood-sucking parasites had ever been, and he plodded up and down

this field, and all over it he sowed his maybe fatal seed--of ticks.

Then four northern cattle were led by Kilborne on to this field--and

in a few weeks their blood ran thin, and one died, and two of the

remaining three had severe bouts of Texas fever but recovered.

VI

So, first of all microbe hunters, Theobald Smith traced out the exact

path by which a sub-visible assassin goes from one animal to another.

In the field where there were southern cattle and ticks, the northern

cattle died of Texas fever; in the field where there were southern

cattle _without_ ticks the northern cows grew fat and remained

happy; in the field where there were no southern cattle but _only_

ticks--there too, the northern cattle came down with Texas fever.

It must be the tick. By such simple, two-plus-two-make-four--but

oh! what endlessly careful experiments, Theobald Smith proved those

western cowmen to have observed a great new fact of nature.... He

chiseled that fact out of folk-shrewdness, just as the anonymous

invention of the wheel has been taken out of folk-inventiveness and

put to the uses of modern whirring dynamos....

You would think he thought he had proved enough--those experiments

were so clear. You would think he would have advised the government

to start an exterminating war on ticks, but that was not the kind

of searcher Theobald Smith was. Instead, he waited for the heat

of the summer of 1890 to come, and then he started doing the same

experiments over, and some new ones too, all of them simple tricks,

but each of them necessary to nail down the fact that the tick was

the real criminal. “How do those bugs carry the disease from a

southern cow to a northern one?” he pondered. “We know now one tick

lives its whole life on just one cow--it doesn’t flit from beast to

beast like a fly....” This was a knotty question--too subtle for the

crude science of the ranchers--and Smith set himself to chew that

knot....

“It must be,” he meditated, “that ticks, when they have sucked enough

blood, and are ripe, drop off, and are crushed, and leave the little

pear-shaped microbes on the grass--to be eaten by the northern

cattle!”

So he took thousands of ticks, sent up in those cans from North

Carolina, and mixed them with hay, and fed them to a susceptible

northern cow kept carefully in a special stable. But nothing

happened; the cow seemed to relish her new food; she got fat.

He tried drenching another cow with mashed up ticks made into

a soup--but that cow too seemed to enjoy her strange dose. She

prospered on it.

It was no go--cows didn’t, apparently, get the microbe by eating

ticks; he was mixed up for a while. And other plaguey questions kept

him awake nights. Why was it that it took thirty days or more, after

the southern tick-loaded cows came on the field, for such a field to

become dangerous? Stockmen knew this too; they knew they could mix

just-arrived southern cows with northern ones, and keep them together

twenty days or so, and then if they took the northern ones away--they

would never get Texas fever; but if you left them in that field a

little longer (even if the southern cows were taken away) bang! would

come the fatal epidemic into the herd of northerners. That was a

poser!

Then one day in this summer of 1890, by the most strange, the most

completely unforeseen of accidents, every jagged piece of the puzzle

fell into its proper place. The solution of the riddle fairly clubbed

Theobald Smith; it yelled at him; it forced itself on him while he

was busy doing other things. He was at all kinds of experiments just

then; he was bleeding northern cows for gallons of blood to give them

an anemia--to make sure those funny little pear-shaped objects he

had found in the corpuscles of Texas fever cattle were microbes, and

not simply little changes in blood that might come from anemia. He

was learning to hatch nice clean young ticks artificially in glass

dishes in his laboratory; he was still laboriously picking ticks

off southern cows--and sometimes he failed to get them all off and

the experiments went wrong--to prove that tickless southern cows

are harmless to northern ones; he was discovering the strange fact

that northern calves get only a mild fever on a field fatal to their

mothers. He fussed about finding every single effect a tick might

have on a northern cow--it might do other damages besides giving her

Texas fever...?

Then came that happy accident. He asked himself: “If I should put

good clean young ticks, hatched in glass dishes in my attic, ticks

who never have been on cattle or on a dangerous field--if I should

put such ticks on a northern cow and let them suck their fill of

her blood--could those ticks take out enough blood to give the cow

an anemia?” It seems to me to have been an aimless question. His

thoughts were a thousand miles away from Texas fever....

But he tried it. He took a good fat yearling heifer, put her in

a box-stall, and day after day put hundreds of clean baby ticks

on her, holding her while these varmints crawled away beneath her

hair to get a good grip on her hide. Then day after day, while the

ticks made their meals, he cut little gashes in her skin to get a

drop of blood to see if she was becoming anemic. And one morning

Theobald Smith came into her stall--for the usual routine--he put

his hand on that heifer.... What was this? She felt hot! Very hot!

Suspiciously too hot! She drooped her head, and would not eat--and

her blood which before had welled out from the gashes thick and rich

and red--that blood ran very thin and darkish. He hurried back to his

attic with samples of the blood between little pieces of glass....

Under the microscope it went, and sure enough!--here were twisted,

jagged, wrecked blood corpuscles instead of good even round ones with

edges smooth as a worn dime. And inside these broken cells--it was

fantastical, this business!--were the little pear-shaped microbes....

Here was the fact, stranger than any pipe-dream--for these microbes

must have come up from North Carolina on old ticks, had gone out of

the old ticks into the eggs they had laid in the glass dishes, they

had survived in the baby ticks hatched out these eggs--and these

babies had at last shot them back, ready to kill, into their destined

but completely accidental victim, that yearling heifer!

In a flash all those mysterious questions cleared up for Theobald

Smith.

It was not the old, blood-stuffed tick but its child, the baby tick,

who sneaked the assassin into the northern cows; it was this little

five- or ten-day-old bug who carried the murderer.

Now he saw why it was that fields took so long to become

dangerous--the mother ticks have to drop off the southern cattle;

it takes them some days to lay their eggs; these eggs take twenty

days or more to hatch; the tick babies have to scamper about to find

a cow’s leg to crawl up on--all that takes many days, weeks. Never

was there a simpler answer to a problem which, without this strange

chance, might not yet be solved....

So soon as he could hatch out other thousands of ticks in warm glass

dishes, Theobald Smith proceeded to confirm his marvelous discovery;

he proved it clean. For every northern cow, on whom he stuck his

regiments of incubator ticks, came down with Texas fever. But he

was a glutton for proofs, as you have seen, and when the summer of

1890 waned and it grew cold, he installed a coal-stove in a stable,

hatched the ticks in a heated place, put a cow in the hot stable,

stuck the little ticks diligently onto the hide of the cow, the stove

instead of the sun made them grow as they should--and the cow got

Texas fever in the winter, a thing which never happens in nature!

For two more summers Smith and Kilborne tramped about their fields,

caulking up every seam in the ship of their research, answering every

argument, devising astounding simple but admirably adequate answers

to every objection the savant horse doctors might make--before these

critics ever had a chance to make objections. They found strange

facts about immunity. They saw northern calves get mild attacks of

Texas fever, a couple of attacks in one summer maybe, and then next

year, more or less grown up, graze unconcerned on fields absolutely

murderous to a non-immune northern cow.... So they explained why

southern cattle never die of Texas fever. This fell disease is

everywhere that ticks are in the South--and ticks are everywhere;

ticks are biting southern cattle and shooting the fatal queer pears

into them all the time; these cattle carry the microbes about with

them in their blood--but it doesn’t matter, for the little sickness

in their calfhood has made them immune.

Finally, after four of these stifling but triumphant summers,

Theobald Smith sat down, in 1893, to answer all the perplexing

questions about Texas fever--and to tell how the disease can

be absolutely wiped out (just then the ancient Pasteur who had

prophesied that about _all_ disease was getting ready to die).

Never--and I do not forget the masterpieces of Leeuwenhoek or Koch or

any genius in the line of microbe hunters--never, I say, has there

been written a more simple but at the same time more solid answer to

an enigma of nature. A bright boy could understand it; Isaac Newton

would have taken off his hat to it. He loved Beethoven, did young

Smith, and for me this “Investigation into the Nature, Causation, and

Prevention of Texas or Southern Cattle Fever” has the quality of that

Eighth Symphony of Beethoven’s sour later years. Absurdly simple in

their themes they both are, but unearthly varied and complete in the

working out of those themes--just as nature is at once simple and

infinitely complex....

VII

And so, with this report, Theobald Smith made mankind turn a

corner, showed men an entirely new and fantastic way a disease may

be carried--by an insect. And only by that insect. Wipe out that

insect, dip all of your cattle to kill all their ticks, keep your

northern cattle in fields where there are no ticks, and Texas fever

will disappear from the earth. To-day whole states are dipping

their cattle and to-day Texas fever which once threatened the great

myriads of American cattle is no longer a matter for concern. But

that is only the beginning of the beneficent deeds of this plain

report, this classic unappreciated and completely out of print.

For presently, on the veldt and in the dangerous bush of southern

Africa, a burly Scotch surgeon-major swore at the bite of a tsetse

fly--and wondered what else besides merely annoying one, these tsetse

flies might do. And a little later in India, and at the same time in

Italy, an Englishman and an Italian listened to the whining song of

swarms of mosquitoes, and dreamed and wondered and planned strange

experiments----

But those are the stories the next chapters will celebrate. They tell

of ancient plagues now in reach of mankind’s complete control--they

tell of a deadly yellow disease now almost entirely abolished. They

tell of men projecting pictures of swarming human life and turreted

cities of the future reaching up and up, built on jungles now fit

only for man-killing wild beasts and lizards. It was this now nearly

forgotten microbe hunting of Theobald Smith that first gave men the

right to have visions of a world transformed.

Microbe hunters · 第 8 / 12 章