,transcrib]'s ,notes3  ,?is is ,pap] #cg
 f ! ,smi?sonian ,in/itution ,unit$     
,/ates ,national ,museum ,bullet9 #bdj1 
compris+ ,pap]s #cd-dd1 :i* w also be   
available z a complete e-book4  ,! front
 mat]ial1 introduction & relevant index 
entries f ! ,bullet9 are includ$ 9 ea*  
s+le-pap] e-book4  ,typographical errors
 h be5 correct$ z foll[s3    ,page #aaj3
 444 ! sp9dle1 to prev5t 444 7_h p9dle7 
,page #abj3 444 s]vants  l'intellig5ce  
de plusieurs *oses difficiles1          
ncessaires 444 7_h a1 plusi]s1          
necessaires7     ,,smi?sonian           
,,in/itution  ,,unit$ ,,/ates ,,national
 ,,museum  ,,bullet9 #bdj   ,illu/ration
  ,,smi?sonian ,,press   ,,museum ,,(   
,,hi/ory ,,& ,,te*nology                
,,contributions   ,,f ,,!   ,,museum    
,,( ,,hi/ory ,,&   ,,te*nology    ,pap]s
 #cd-dd   ,on ,sci5ce & ,te*nology      
,,smi?sonian ,,in/itution  ,,wa%+ton1   
,d4,c4 #aiff     ,publications ( !      
,unit$ ,/ates ,national ,museum   ,!    
s*ol>ly & sci5tific publications ( !    

,unit$ ,/ates ,national ,museum include 
two s]ies1 ,proce$+s ( ! ,unit$ ,/ates  
,national ,museum & ,unit$ ,/ates       
,national ,museum ,bullet94  ,9 ^!      
s]ies1 ! ,museum publi%es orig9al       
articles & monographs deal+ ) !         
collections & "w ( its con/itu5t        
museums--,! ,museum ( ,natural ,hi/ory &
 ! ,museum ( ,hi/ory & ,te*nology--sett+
 =? newly acquir$ facts 9 ! fields (    
an?ropology1 biology1 hi/ory1 geology1 &
 te*nology4 ,copies ( ea* publication   
are di/ribut$ to libr>ies1 to cultural &
 sci5tific organizations1 & to          
speciali/s & o!rs int]e/$ 9 ! diff]5t   
subjects4  ,! ,proce$+s1 begun 9 #ahgh1 
are int5d$ = ! publication1 9 sep>ate   
=m1 ( %ort] pap]s f ! ,museum ( ,natural
 ,hi/ory4 ,^! are ga!r$ 9 volumes1      
octavo 9 size1 ) ! publication date (   
ea* pap] record$ 9 ! table ( cont5ts ( !
 volume4  ,9 ! ,bullet9 s]ies1 ! fir/ ( 
:i* 0 issu$ 9 #ahge1 appe> long]1       
sep>ate publications consi/+ (          
monographs 7occasionally 9 sev]al p>ts7 

& volumes 9 :i* are collect$ works on   
relat$ subjects4 ,bullet9s are ei!r     
octavo or qu>to 9 size1 dep5d+ on ! ne$s
 ( ! pres5tation4 ,s9ce #aijb pap]s     
relat+ to ! botanical collections ( !   
,museum ( ,natural ,hi/ory h be5 publi%$
 9 ! ,bullet9 s]ies "u ! head+          
,contributions f ! ,unit$ ,/ates        
,national ,h]b>ium1 & s9ce #aiei1 9     
,bullet9s titl$ ,contributions f !      
,museum ( ,hi/ory & ,te*nology1 h be5   
ga!r$ %ort] pap]s relat+ to !           
collections & rese>* ( t ,museum4  ,!   
pres5t collection ( ,contributions1     
,pap]s #cd-dd1 comprises ,bullet9 #bdj4 
,ea* ( ^! pap]s has be5 previ\sly       
publi%$ 9 sep>ate =m4 ,! ye> (          
publication is %[n on ! la/ page ( ea*  
pap]4    ,,frank ,a4 ,,taylor           
,director1 ,unit$ ,/ates ,national      
,museum     ,,contributions ,,f ,,!     
,,museum ,,( ,,hi/ory ,,& ,,te*nology3  
,,pap] #cg  ,,screw-,,?read ,,cutt+ ,,by
 ,,! ,,ma/]-,,screw ,,me?od ,,s9ce #adhj
  ,edw9 ,a4 ,battison     ,edw9 ,a4     

,battison  ,,screw-,,?read ,,cutt+ ,,by 
,,! ,,ma/]-,,screw ,,me?od ,,s9ce #adhj 
,among ! e>lie/ kn[n examples (         
screw-?read cutt+ ma*9es     are !      
screw-cutt+ la! ( #adhc1 kn[n only 9    
pictures &     draw+s1 & an in/rum5t ( !
 trav]se-sp9dle v>iety =     ?read+     
metal1 n[ 9 ! ,smi?sonian ,in/itution1  
dat+ f !     late #ag? or e>ly #ah?     
c5tury4 ,! au?or %[s cle>ly _!          
evolution f some?+ q specializ$ to !    
pres5t-day tool4     ,he has trac$ !    
pat5ts = ^! in/rum5ts ?r\gh ! e>ly      
#aicj's & f ?is rese>* we see ! "p play$
 by su* devices     9 ! developm5t ( !  
ma*9e-tool indu/ry4      ,,! ,,au?or3   
,edw9 ,a4 ,battison is associate curator
 ( me*anical     & civil eng9e]+ 9 !    
,smi?sonian ,in/itution's ,museum (     
,hi/ory & ,te*nology4   ,directness &   
simplicity *>act]ize pione] ma*9e tools 
because !y 7 int5d$ to accompli% "s q   
specializ$ task & ! ne$ = v]satility 0 n
 app>5t4 ,hi/ory does n reveal ! e>lie/ 
=ms ( any primitive ma*9es nor does x   

reveal mu* ab\t ! v>i\s e>ly /ages 9    
evolution t[>d m complex types4 ,at be/ 
we h discov]$ & dat$ c]ta9 developm5ts z
 exi/+ 9 p>ticul> areas4 ,:e!r ^! =ms 7 
new at ! "t !y 7 fir/ f\nd or h[ widely 
disp]s$ su* =ms may h be5 is unkn[n4    
,surviv+ evid5ce is 9 ! =m ( pictures or
 draw+s1 su* z ! little-kn[n screw-cutt+
 la! ( #adhc 7fig4 #a7 %[n 9 ,das       
mittelalt]li*e ,hausbu*4  ,?is la! %[s t
 its build] _h a ke5 p]ception ( !      
necess>y elem5ts1 r$uc$ to b>e          
ess5tials1 requir$ to accompli% !       
object4 ,pres5t are ! coord9ate slides  
(t5 cr$it$ to ,h5ry ,maudslay4 ,8 slides
 are n1 ( c\rse1 associat$ ) ! sp9dle2  
nei!r is !re any natural law :i* compels
 !m to guide ! tool exactly p>allel ) ! 
axis ( revolution4 ,9 ?is s5se !        
screw-cutt+ la! 9 ! ,hausbu* is sup]ior 
because x is 9 h>mony ) natural law & c 
g5]ate a true cyl9d]1 :]eas ,maudslay's 
la! c only transf] to ! "w :atev]       
accuracy is built into x4  ,9 pr9ciple  
?is ma*9e %[n 9 ! ,hausbu* is v advanc$ 

z we see :5 we foll[ ! design ?r\gh to !
 pres5t "t4 ,! arti/1 ^: draw+s give u  
our only k ( ! ma*9e1 himself 0 obvi\sly
 n v famili> ) ! details ( its function4
 ,ref]5ce to figure #a %[s t ! ?reads on
 ! lead screw & on ! "w1 w9d 9 opposite 
directions4 ,?is mu/ be an error 9      
del9eation s9ce ! two are closely c\pl$ 
toge!r )\t any int]v5+ me*anism s t !   
only possible result on ! "w mu/ be a   
?read w9d+ 9 ! same direction z on !    
orig9al screw4 ,! "w also is %[n ?read$ 
= its entire l5g?2 ?is _c be accompli%$ 
) any "o location ( ! cross-slide4 ,we  
are left ) ! "q ( :e!r ?is slide 0 us$ 9
 two locations or :e!r ! arti/1 possibly
 work+ f notes or an e>li] r\gh sket*1  
fail$ to %[ an un?read$ portion on "o   
end or ! o!r ( ! "w4  ,illu/ration3     
,figure #a4--;,,e>lie/ ,,repres5tation  
,,f\nd ,,( ,a ,,ma/]-,,screw ,,type (   
?read-cutt+ ma*9e4 ,f ! inconsi/5cies1  
su* z "r- & left-h& ?reads on ma/] & "w1
 x appe>s t ! arti/ _h scant insight    
into actual function4 ,f plate #fb (    

,das mittelalt]li*e ,hausbu*1 na* dem   
,orig9ale im ,besitze des ,fr/5 von     
,waldburg-,wolfegg-,waldsee1 im         
,auftrage des ,deuts*5 ,v]e9s fr        
,kun/wiss5s*aft1 h]ausgegeb5 von ,helmu?
 ,?4 ,boss]t und ,willy ,f4 ,/orck      
7,leipzig3 ,e4 ,a4 ,seemann1 #aiab74  ,(
 at lea/ equal importance ) ! lead screw
 & "w & _! relation%ip to ea* o!r is !  
tool-support ) its screw-adju/$         
cross-slide 7fig4 #b74 ,j h[ ?is 0      
atta*$ to ! frame ( ! ma*9e s t x plac$ 
! tool at a suitable radius is aga9 a   
que/ionable po9t4 ,! v well-develop$    
cutt+ tool is %>p5$ to a ?91 ke5 edge   
totally unsuit$ = cutt+ metal b ideal = 
use on a s(t]1 fibr\s sub/ance3         
und\bt$ly wood1 9 ?is in/ance4          
,un=tunately1 ! angle at :i* ! arti/    
*ose to %[ u ?is cutt] is n a view f :i*
 x is possible to judge :e!r or n ! tool
 has be5 made to con=m to ! helix angle 
( ! ?read to be cut4 ,?is cross-slide1 9
 conjunction ) ! trav]s+ "w sp9dle1     
gives u a ma*9e hav+ two coord9ate      

slides yield+ ! same effect z ! slide   
re/ usually attribut$ to ,h5ry ,maudslay
 at ! end ( ! #ah? c5tury4 ,actually1 an
 illu/ration ( coord9ate slides         
indep5d5t ( ! sp9dle _h be5 publi%$ z   
e>ly z #aefi by ,besson#a & k ( !m      
widely dissem9at$ by 8 popul> "w on     
me*anics4 ,^! slides are %[n z "p ( a   
screw-cutt+ ma*9e ) a que/ionably       
adequate connection1 by means ( cords1  
betwe5 ! ma/] screw & ! "w4  ,x 0 !     
au?or's pleasure rec5tly to obta9 = !   
,smi?sonian ,in/itution & id5tify a     
small1 nicely made1 brass in/rum5t :i*  
_h be5 9 two collections 9 ?is c\ntry & 
"o collection 9 ,g]many z an unid5tifi$ 
locksmi?'s tool 7fig4 #c74 ,?is prov$ to
 be an in/rum5t ( ! trav]se-sp9dle      
v>iety = ?read+ metal4 ,=tunately1 all  
ess5tial details 7 pres5t includ+ a     
cutt] 7,a 9 figure #d72 ?is in/rum5t 0  
id5tifi$ by ! signature ,manuel         
,wets*gi1 ,augspurg4 ,! ,wets*gis 7 a   
well-kn[n family ( gunsmi?s & me*anics 9
 ,augsburg ?r\gh sev]al g5]ations4 ,two 

bore ! giv5 "n ,emanuel3 ! e>li] 0 born 
9 #afgh & di$ 9 #agbh4 ,he 0 q celebrat$
 9 8 field ( rifle mak+ & became *ief ( 
artill]y to ! ,l&grave ( ,hesse-,kassel 
%ortly be=e 8 dea? 9 8 #ea/ ye>4 ,little
 is kn[n ( ! lat] ,emanuel ,wets*gi     
except t he 0 at ,augsburg 9 #agdj4     
,t5tative attribution ( ! in/rum5t has  
be5 made to ! e>li] ,emanuel1 *iefly on 
! basis ( 8 recogniz$ position z an     
out/&+ craftsman4  ,illu/ration3 ,figure
 #b4--;,,cross-,,slide = ! ?read-cutt+  
la! ( ,das mittelalt]li*e ,hausbu*1 %[n 
9 figure #a4 ,x is rem>kable n only =   
its e>ly date1 b also = its high /ate ( 
developm5t ) a crossfe$ screw :i* _h n  
become univ]sally accept$ #cjj ye>s     
lat]4 ,! cutt]1 %[n out ( its socket1 is
 obvi\sly %>p5$ = use on wood4  ,9      
sev]al respects ?is little ma*9e diff]s 
f its pr$ecessor ( ! ,hausbu*1 z might  
be expect$ :5 all[ance is made = !      
g5]ations ( craftsm5 :o und\bt$ly work$ 
) su* tools ov] ! r\ghly #bjj ye>s ( "t 
sep>at+ !m4 ,ano!r factor to consid] :5 

comp>+ ^! two ma*9es is t "o 0 us$ on   
metal1 ! o!r probably only on wood4     
,!re=e1 x is n surpris+ to f9d on ! lat]
 ma*9e an outbo>d or tail/ock support = 
! "w4 ,! sp9dle ( ?is support has to    
travel 9 unison ) ! "w-driv+ sp9dle s t 
x is n an unexpect$ discov]y to f9d t x 
is spr+-load$4 ,figure #e %[s h[ ?is    
spr+ may be adju/$ to accommodate v>i\s 
l5g?s ( "w by mov+ ! atta*m5t screw to  
v>i\s holes 9 bo? ! spr+ & 9 ! frame4   
,also visible 9 ! same illu/ration is a 
rectangul> projection at ! o!r end ( !  
spr+ :i* engages a mat+ hole 9 !        
tail/ock sp9dle to prev5t its rotation4 
,illu/ration3 ,figure #c4--,,small      
,,?read-,,cutt+ ,,la! :i* 0 made to be  
held 9 a vise dur+ use4 ,x 0 f\nd z %[n 
"h1 ) only ! op]at+ crank miss+4 ,!     
ov]all l5g? is approximately #ab in*es1 
dep5d+ on ! adju/m5t ( p>ts4            
7,smi?sonian photo #dfebe;,b47  ,figure 
#f %[s ! trav]s+ sp9dle & nut remov$ f !
 ma*9e4 ,provision has be5 made = do+   
?is s easily t !re is e reason to       

believe t1 orig9ally1 !re 7 v>i\s       
diff]5t sp9dle & nut units :i* c\ld be  
int]*angeably us$ 9 ! ma*9e4 ,additional
 evid5ce t5d+ to support ?is concept    
exi/s 9 ! cutt+ tool 7fig4 #d71 :i* mu/ 
h be5 int5d$ = s]i\s "w z x has be5     
c>efully fitt$ 9 its unsymmetrical      
socket4 ,! cutt+ blade ( ?is tool1 :i*  
works ) a scrap+ r ?an a true cutt+     
action1 is too wide to =m a prop]ly     
proportion$ ?read :5 us$ ) ! exi/+ lead 
screw4 ,?is may well indicate t ! tool 0
 made = use ) a lead ( co>s] pit*1 n[   
lo/4  ,illu/ration3 ,figure #d4--,,!    
,,work+ ,,area ( figure #c1 %[+ ! tool &
 signature4 7,smi?sonian photo          
#dfebe;,a47  ,p]haps ! mo/ />tl+ feature
 ( ?is ma*9e :5 comp>$ ) ! ma*9e ( !    
,hausbu*1 is ! abs5ce ( a cross-slide = 
adju/+ ! tool4 ,possibly ?is c be       
expla9$ by ! blunt scrap+ edge on !     
tool4 ,9 actual use1 rec5tly1 to cut a  
sample screw1 us+ a tool simil> to ! "o 
f\nd 9 ! ma*9e 7fig4 #g71 x 0 f\nd      
advantage\s to be free ( a cross-slide &

 ?us be able to fe$ ! tool into ! "w by 
feel r ?an by rule1 z w\ld be done ) a  
slide re/4 ,9 ?is way1 x 0 possible to  
?read /eel )\t te>+1 z ! cutt+ pressure 
c\ld readily be felt & ! tool c\ld      
release itself f too heavy a cut4 ,size 
on sev]al screws c\ld be repeat$ by     
sett+ ! tool to produce ! desir$ diamet]
 :5 its support+ arm came to re/ aga9/ !
 frame ( ! ma*9e4 ,! screws us$ 9 !     
ma*9e itself 7 app>5tly made 9 j su* a  
way4 ,!y 7 n cut ) a die z ! ?read bl5ds
 v gradually into ! body ( ! screw )\t !
 *>act]i/ic m>ks left by ! cutt+ edges (
 a die4 ,?reads cut ) a s+le-po9t tool  
controll$ by a cross-slide usually end  
ev5 m abruptly ?an ^? cut by a die1 :ile
 x w\ld be q simple ) a ma*9e ( ! nature
 we are consid]+ to br+ ! ?read to a    
g5tle tap]+ end z se5 9 figure #h 7ano!r
 view ( ! screw ,a 9 fig4 #c7 by        
gradually releas+ ! pressure necess>y to
 keep ! tool cutt+ z ! end ( ! ?read 0  
approa*$4  ,illu/ration3 ,figure        
#e4--,,spr+ ,,= ,,keep+ ,,! ,,foll[]    

,,sp9dle aga9/ ! "w1 %[+ ! me?od & range
 ( adju/m5t4 ,note ! rectangul>         
projection to engage a mat+ socket 9 !  
sp9dle1 to prev5t sp9dle rotation4      
7,smi?sonian photo #dfebe47             
,illu/ration3 ,figure #f4--,,"w ,,sp9dle
 ,,& ,,its ,,nut remov$ f ! ma*9e to    
illu/rate h[ easily ano!r sp9dle & nut (
 diff]5t pit* c\ld be sub/itut$4        
7,smi?sonian photo #dfebe;,c47  ,t      
ma*9es ( ?is g5]al type hav+ ! lead     
screw on ! axis ( ! "w 7 competitive )  
o!r me?ods & o!r types ( ma*9es ov] a   
long p]iod ( "t may be se5 f figures #i 
& #aj4 ,! ma*9e1 left front 9 figure #i 
& 9 m intimate detail 9 figure #aj1 c be
 se5 to diff] little f t %[n 9 ,das     
mittelalt]li*e ,hausbu* ( #adhc4 ,!     
d\ble "w-support is1 ( c\rse1 a great   
improvem5t1 :ile ! tool-support is      
regressive s9ce x lacks a fe$ screw4  ,!
 developm5t ( eng9e]+ !ory1 c\pl$ ) !   
ris+ ne$s ( indu/ry1 p>ticul>ly ) !     
adv5t ( ! ,indu/rial ,revolution1 br\ght
 ab\t accel]at$ developm5t ( screw-cutt+

 la!s ?r\gh ! comb9ation ( screw-cutt+  
ma*9es ) simple la!s z se5 9 figure #i &
 9 detail 9 figure #aa4 ,"o important   
advance %[n "h is driv+ ! ma*9e by means
 ( a cord or b& s t any means ( rot>y   
p[] c\ld be appli$1 n j h& or foot p[]4 
,( great] int]e/ & te*nical importance  
to ?is /udy is ! provision1 se5 to bett]
 advantage 9 figure #aa1 = readily *ang+
 f "o ma/] lead screw to ano!r4 ,?is _h 
already be5 a*iev$ 9 ! ,manuel ,wets*gi 
ma*9e1 z f> z v]satility is conc]n$1    
al?\gh n 9 q su* a conv5i5t way4        
,illu/ration3 ,figure #g4--,,?read ,,(  
,,mod]n ,,=m rec5tly cut1 us+ ! old     
screw & nut b ) a new tool4 ,! mat]ial  
?read$ is c>bon-/eel drill rod4         
7,smi?sonian photo #dibgf;,a47  ,figure 
#ab1 ! head/ock ( ano!r & m advanc$ la! 
?an %[n 9 figures #i & #aa b ( ! same   
type1 %[s keys 7,d71 ea* ( :i* is a     
p>tial nut ( diff]5t pit* to engage ) a 
?read ( mat+ pit*4 ,! dott$ l9es 9      
figure #ac %[ ! engag$ & dis5gag$       
positions ( "o ( ^! keys1 & figure #ad  

%[s ! sp9dle ) ! v>i\s leads1 ,c4 ,at ,d
 is a groov$ coll> to be engag$ by !    
n>r[ key %[n 9 op]at+ position at ! left
 9 figure #ab = ! purpose ( controll+ ! 
endwise movem5t ( ! sp9dle :5 us$ =     
ord9>y turn+ in/ead ( ?read-cutt+4 ,9   
return = great] conv5i5ce & fre$om f !  
exp5se ( ! _m sep>ate sp9dles1 z typifi$
 by ! ,wets*gi ma*9e1 a sacrifice has   
be5 made 9 ! l5g? ( ! ?read :i* c be cut
 )\t int]ruption4  ,illu/ration3 ,figure
 #h4--;,,b9d+ ,,screw se5 at ,a 9 figure
 #c1 %[+ ! long smoo? fade\t ( ! ?read  
bel[ ! %\ld]4 7,smi?sonian photo        
#dibgf47  ,illu/ration3 ,figure         
#i4--,,mak+ ,,screws ,,9 ,,france 9 !   
?ird qu>t] ( ! #ah? c5tury4 ,f          
,l',encyclopdie1 ou dictionnaire raisonn
 des sci5ces1 des arts et des mti]s 444 
receuil de plan*es sur les sci5ces1 les 
arts libraux1 et les arts m*aniques1    
avec leur explication 7,p>is3           
#agfb-aggb71 vol4 #i1 plate #a4         
,illu/ration3 ,figure #aj4--;,,details  
,,( ,,! ,,ma*9e 9 ! left =egr\nd (      

figure #i1 %[+ ! crude tool-support )\t 
screw adju/m5t4 ,f ,l',encyclopdie1 vol4
 #i1 plate #b4  ,?is r$uction 9 ! l5g? t
 c\ld conv5i5tly be ?read$ 0 no great   
drawback on _m classes ( "w4 ,?is c be  
realiz$ f figure #af :i* %[s a          
trav]se-sp9dle la! head/ock typical ( ! 
mid-#ai? c5tury4 ,dur+ ! ye>s int]v5+   
betwe5 ! ma*9es ( figures #ab & #af1 !  
g5]al design 0 greatly improv$ by remov+
 ! lead screws f ! c5t] ( ! sp9dle4 ,?is
 made possible a %ort]1 mu* /iff] sp9dle
 & support$ bo? ends ( ! sp9dle 9 "o    
frame or head/ock r ?an 9 sep>ate pieces
 atta*$ to ! b$4 ,! screws 7 n[ m\nt$   
outside ( ! sp9dle-be>+s1 "o at a "t1   
:ile ! mat+ nuts 7 cut p>tially into !  
circumf]5ce ( a disk :i* c\ld be turn$  
to br+ any p>ticul> nut into work+      
position z requir$4 ,) ?is arrangem5t1 a
 wide v>iety ( leads ei!r "r or left h& 
c\ld be provid$ & additional leads c\ld 
be fitt$ at any future "t4 ,screw-cutt+ 
la!s ( ?is design 7 popul> = a v long "t
 ) in/rum5t mak]s & opticians :o _h     

little ne$ to cut screws ( great l5g?4  
,illu/ration3 ,figure #aa4--;,,details  
,,( ,,! ,,?read+ ,,la! se5 9 ! "r       
=egr\nd ( figure #i %[+ ! me?od ( drive 
& support = ! "w4 ,f ,l',encyclopdie1   
vol4 #i1 plate #a4  ,! dem&s ( exp&+    
indu/ry = great] v]satility 9 !         
production ( eng9e]+ elem5ts late 9 !   
#ah? c5tury set ! /age = ! evolution ( m
 complex ma*9es t5d+ to place ! ?read$  
sp9dle la!s 9 eclipse4 ,maudslay's la! (
 #agig-ahjj 7fig4 #ae7 appe>$ at ?is "t 
:5 indu/ry 0 receptive to rapid         
innovation4 ,un=tunately1 ! ge>+ :i*    
once exi/$ to connect ! head/ock sp9dle 
) ! lead screw has long be5 lo/4 ,at ?is
 "t x is q difficult to say ) c]ta9ty   
:e!r ! orig9al ge> set (f]$ a v>iety (  
ratios1 z 0 true ( slightly lat]        
,maudslay la!s1 or a fix$ ratio4 ,!     
plausibility ( ! fix$ ratio !ory is     
support$ by ! v conv5i5t means1 se5 9   
figure #ae1 = remov+ ! lead screw 9     
prep>ation = sub/itution ( "o ( ano!r   
pit*4 ,all t is requir$ is to back (f   

its support+ c5t] at ! tail/ock end &   
)draw ! screw f its split nut#b & f !   
driv+ clut* ne> ! head/ock4 ,?is split  
nut also w\ld h to be *ang$ to "o ( a   
pit* correspond+ to t ( ! screw4 ,:ile m
 exp5sive ?an a solid nut1 x neatly     
circumv5ts ! ne$ 7& saves ! "t involv$7 
to rev]se ! screw 9 ord] to get ! tool  
back to ! po9t ( beg9n+ prelim9>y to    
tak+ ano!r cut4 ,david ,wilk9son's la! (
 #agih 7fig4 #ag7 :i* 0 develop$ 9      
,rhode ,isl& at ! same "t %[s ! same    
me?od ( m\nt+ & driv+ ! ma/] screw4 ,at 
lea/ 9 ! ,unit$ ,/ates1 ?is me?od (     
*ang+ ! lead screw in/ead ( us+ *ange   
ge>s rema9$ popul> = _m ye>s4 ,examples 
( ?is *angeable screw feature are to be 
f\nd 9 ! la!s con/ruct$ = ! pump factory
 ( ,w4  ,b4 ,d\glas ,company1           
,middlet[n1 ,connecticut1#c 9 ! #ahcj's4
 ,middlet[n1 at t "t "o ( ! lead+       
metal-work+ c5t]s 9 "o ( ! *ief         
indu/rial ,/ates1 _h be5 = _m ye>s !    
site ( ! ,simeon ,nor? arms factory :i* 
rival$ ,:itney's4 ,9 ?is atmosph]e1 x is

 reasonable to expect t ma*9]y con/ruct$
 by local me*anics1 z 0 ! cu/om 9 ^?    
days1 w\ld reflect ! mo/ accept$        
ref9em5ts 9 ma*9e design4  ,illu/ration3
 ,figure #ab4--,,well-,,develop$        
,,example ( la! head/ock hav+ sev]al    
leads on ! sp9dle & provision = m\nt+ ! 
"w or a "w-hold+ *uck on ! sp9dle4      
,adapt$ f ,l',encyclopdie1 vol4 #aj1    
plate #ac4  ,illu/ration3 ,figure       
#ac4--;,,end ,,view ,,( ,,! ,,head/ock  
se5 9 figure #ab1 %[+ ! keys or half    
nuts :i* engage ! ?read$ sp9dle1 9      
engag$ & dis5gag$ positions4 ,f         
,l',encyclopdie1 vol4 #aj1 plate #ac4   
,illu/ration3 ,figure #ad4--,,sp9dle ,,(
 ,,figures #ab ,,& #ac1 %[+ ! sev]al    
leads & ! _m-sid$ seat = ! driv+ pulley4
 ,note ! scale ( feet4 ,f               
,l',encyclopdie1 vol4 #aj1 plate #af4   
,r\ghly tw5ty ye>s lat]1 ,joseph ,nason 
( ,new ,york pat5t$#d ! comm]cially v   
important ,fox brasswork]'s la! 7fig4   
#ah74 ,:ile ?is does h a ratio 9 ! pair 
( ge>s connect+ ! "w sp9dle & ma/]      

screw1 x is cle> f ! pat5t t v>i\s      
pit*es are to be obta9$ by *ang+ screws1
 n by *ang+ ge>s4 ,! pat5t sums x up z  
foll[s3       ,a nut ^u ! end ( ! /ud   
444 is unscrew$ :5 ! guide      screw is
 to be remov$ or *ang$4 ,! two :eels 444
 %\ld h      9 _! numb] ( tee? a common 
multiple4 ,!y are seldom or      nev]   
remov$ & _! diamet]s are made dissimil> 
only = !      purpose ( giv+ to ! guide 
screw a sl[] rate ( motion ?an      t ( 
! m&rel :]eby x may be made ( co>s] pit*
 ?an      t ( ! screw to be cut & its   
we> mat]ially less5$4  ,! introduction (
 ge>+ betwe5 ! sp9dle & ! lead screw1 = 
:atev] purpose1 c\ld n help b introduce 
v>iable factors caus$ by inaccuracies 9 
! ge>s !mselves & 9 _! m\nt+4 ,^! 7 (   
little consequ5ce = common "w1          
p>ticul>ly :5 c\pl$ to a screw :i*1     
itself1 0 ( que/ionable accuracy4 ,!    
increas+ ref9em5ts dem&$ 9 sci5tific    
in/rum5ts & 9 ma*9e tools !mselves aft] 
!y _h rea*$ a relatively /able =m       
dictat$ t att5tion be d$icat$ to improv$

 accuracy ( ! ?read$ compon5ts4         
,illu/ration3 ,figure                   
#ae4--,,maudslay',s ,,well-,,kn[n       
screw-cutt+ la! ( #agig-ahjj1 %[+ !     
me?od ( m\nt+ & driv+ *angeable ma/]    
screws4 7,photo c\rtesy ( ,! ,sci5ce    
,museum1 ,london47  ,illu/ration3       
,figure #af4--;,,head/ock ,,( ,a ,,g]man
 ,,in/rum5t-,,mak]',s ,,la!1 typical ( !
 mid-#ai? c5tury1 %[+ ! trav]se sp9dle1 
int]*angeable lead screws1 &            
semicircumf]5tial nut conta9+ sev]al    
leads4 ,! nut may be br\ght into        
engagem5t by ! lev] at top re> ( !      
head/ock4 ,?is releases ! end ?ru/      
control on ! sp9dle simultane\sly )     
engagem5t ( ! nut4 7,smi?sonian photo   
#dihci47  ,illu/ration3 ,figure         
#ag4--;,,david ,,wilk9son',s            
,,screw-,,cutt+ ,,la!1 pat5t$ 9 ! ,unit$
 ,/ates 9 #agih4 ,note ! ready facility 
) :i* ! lead screw may be ex*ang$ =     
ano!r & ! same means ( support+ & driv+ 
z 9 figure #ae4 7,u4,s4 ,national       
,ar*ives photo47  ,an attack on ?is     

problem1 :i* int]e/+ly rev]ts to !      
fundam5tal pr9ciple ( motion d]iv$ f a  
ma/] screw )\t ! int]v5tion ( o!r       
me*anism 7fig4 #ai71 is cov]$ by a      
pat5t#e issu$ to ,*>les ,v&] ,wo]d1     
"o-"t sup]9t5d5t ( ! ,wal?am ,wat*      
,company4 ,! problem is well /at$ 9 !   
pat5t3       ,?is inv5tion relates to ! 
manufacture ( lead+ screws to be        
us$ = purposes requir+ ! highe/         
atta9able degree (      correctness 9 ! 
cutt+ ( ! screw-?reads ( said screw 444 
z1 = example1 9 ma*9es = rul+ l9es 9    
glass plates to      produce refraction 
sic grat+s = ! resolution ( ! l9es      
( ! sol> spectrum1 su* ma*9es be+       
requir$ to rule _m      ?\s&s ( l9es on 
an in* ( space by a m>k+ device :i* is  
reciprocat$ ov] ! glass plate & is f$ by
 ! action ( a      lead+ screw aft] !   
=mation ( ea* l9e4 ,great difficulty    
has be5 exp]i5c$ 9 con/ruct+ a lead+    
screw = ?is &      o!r purposes1 9 :i* !
 ?read is s ne>ly correct z to          
produce no p]ceptible v>iation 9 !      

microscopic spaces betwe5      ! rul$   
l9es or grat+s4444 ,v>i\s causes prev5t 
!      =mation ( a ?read on ! rod or    
blank1 :i* is absolutely      uni=m &   
accurate f end to end ( ! rod4 ,among   
o!r causes      are ! v>iations (       
temp]ature f "t to "t1 !                
imp]fections ( ! op]at+ lead+ screw1 !  
spr++ ( !      lead+ screw & ( ! rod t  
is be+ ?read$1 & o!r      unavoidable   
causes1 all ( :i*1 al?\gh app>5tly      
trivial &      produc+ only slight      
v>iations 9 ! ?read at diff]5t p>ts     
( ! rod or blank1 are ( suffici5t mom5t 
to be s]i\sly      consid]$ :5 a screw (
 absolute accuracy is desir$4           
,illu/ration3 ,figure #ah4--,,nason',s  
,,la!1 pat5t$ 9 #ahed1 %[+ a ma/] lead  
screw driv5 at less ?an "w spe$ s t !   
ma/] c\ld be ( a co>s] & m durable pit* 
?an ! "w4 ,u4,s4 pat5t #ajchc4  ,x is   
int]e/+ to note 9 figure #ai t ,v&]     
,wo]d's ma*9e1 to avoid ! problems      
outl9$ 9 8 pat5t1 has return$ to a />kly
 simple design4 ,we are n told1 h[ev]1  

h[ he orig9at$ ?is ma/] screw :i* is us$
 to produce ! accurately ?read$ "w      
pieces4 ,lat] g5]ations1 9 ! se>* =     
ev]-great] accuracy1 also return$ to !  
fundam5tal simplicity ( a ma/] screw z  
we %all see :5 we consid] ! ref9em5ts 9 
me*anism necess>y to ! ext5d$ developm5t
 ( ! automobile & ! airplane4           
,illu/ration3 ,figure #ai4--,,v&]       
,,wo]d',s ,,pat5t1 se5 "h1 cov]$ !      
comb9ation ( a ma/] screw1 toolslide &  
"w 9 a rigid frame to be support$ &     
driv5 by outside means ( no requir$     
precision4 ,u4,s4 pat5t #bicicj dat$    
,febru>y #ahhd4  ,z ! p[] & spe$ (      
automobiles & aircraft increas$1        
critical p>ts became m highly /ress$4   
,ge>s & ?read$ p>ts 7 p>ticul>ly        
tr\blesome details ( ! me*anism because 
( ! /resses conc5trat$ 9 !m1 &1 9 ! case
 ( ge>s1 because ( ! int]nal & ext]nal  
/resses orig9at+ 9 m9ute deviations f ! 
ideal ( too? =m & spac+4 ,! problems 7 n
 entirely new b _h hi!rto be5 solv$ by  
increas+ ! size ( ! p>ts1 an av5ue (    

limit$ utility to design]s 9 ^! fields  
:]e total weight z well z ! effects (   
mass & in]tia are s important4 ,by mak+ 
^! p>ts ( heat-treat$ /eel1 ! /r5g? c\ld
 be made suitable :ile ! size & mass ( !
 p>ts 7 kept )9 b\nds4 ,! necess>y      
processes ( heat-treat+ 7 n always      
applicable to f9i%$ p>ts z !y sometimes 
de/roy$ bo? f9i% & accuracy4 ,gr9d+1 :i*
 0 well develop$ = ! simple plane1      
cyl9drical1 & conical surfaces s widely 
us$ 9 me*anisms1 _h to be ext5d$ to     
?reads & ge>s s t !y c\ld be f9i%$ aft] 
heat-treat+4 ,sometimes ! ge> tee?      
!mselves 7 gr\nd2 = o!r applications x 0
 suffici5t to improve ! accuracy ( ! ge>
 cutt]s4  ,illu/ration3 ,figure         
#bj4--;,a ,,hob-,,gr9d+ ,,ma*9e pat5t$ 9
 #aicb & incorporat+ ! ma/]-screw       
pr9ciple4 ,c>l ,g4 ,olson's ,u4,s4 pat5t
 #ahgdeib4  ,attempts to produce ge>    
hobs free ( ! imp]fections & di/ortions 
introduc$ by heat treatm5t l$ to ano!r  
return to ! use ( ! ma/] lead screw4    
,figure #bj illu/rates a ma*9e hav+ ?is 

feature :i* 0 pat5t$ 9 #aicb by ,c>l ,g4
 ,olson4#f ,9 speak+ ( ! sp9dle-driv+   
me*anism disclos$ 9 e>li] pat5ts1 !     
pat5t goes on to say3       ,?is driv+  
me*anism includes an integral sp9dle    
#bj1 "o      extremity !re( be+ design$ 
= support+ a hob #bb & !      o!r       
extremity !re( be+ =m$ s z to pres5t a  
lead screw      #bd4 ,! sp9dle #bj is   
m\nt$ betwe5 a be>+ #bf & a be>+        
#bh1 ! latt] be>+ provid+ a nut 9 :i* ! 
lead screw #bd      rotates4444 ,f !    
description ?us f> giv5 x w be app>5t   
t ! rotation ( ! lead screw #bd )9 !    
be>+ or nut #bh      w cause ! hob to be
 mov$ axially1 ! lead ( ! screw #bd     
be+ equal to ! lead ( ! ?read 9 ! hob4  
,claim #h :i* concludes ! descriptive   
portion ( ! pat5t /ates 9 "p3       ,9 a
 hob gr9d+ ma*9e ( ! class describ$1 a  
rot>y "w      support+ sp9dle1 means =  
effect+ longitud9al movem5t (      !    
sp9dle1 a tool hold] = support+ a gr9d+ 
:eel 9      op]ative position ) respect 
to ! "w support$ by !      sp9dle dur+ !

 rot>y & longitud9al movem5t !re(1 444  
,ev5 be=e ?is pat5t 0 appli$ =1 ano!r   
pat5t 0 p5d+ = ! purpose ( modify+ !    
pit* ( ! lead screw )\t ! use ( *ange   
ge>s 9 spite ( ! wide acceptance ( su*  
ge> me*anisms = ov] a hundr$ ye>s4      
,illu/ration3 ,figure #ba4--;,a         
,,hob-,,gr9d+ ,,ma*9e ,,( #aicc1 %[+ use
 ( ! ma/] screw ) a modifi] b )\t *ange 
ge>s4 ,c>l ,g4 ,olson's ,u4,s4 pat5t    
#aijaibf4  ,illu/ration3 ,figure        
#bb4--;,a ,,s9e-,,b> ,,device to modify 
! effective lead ( a ma/] lead screw )\t
 introduc+ a complex me*anism :i* w\ld  
be bo? difficult to make & to op]ate )9 
! requir$ close limits4 ,c>l ,g4        
,olson's 7#aicc7 ,u4,s4 pat5t #aijaibf4 
,figure #ba %[s a plan view#g ( ! ma*9e1
 & figure #bb a detail$ view ( ! s9e-b> 
me*anism actuat$ by ! ma/] screw1 #f1 to
 modify ! effective pit* ( ! lead screw 
9 accordance ) ! realities ( practice z 
/at$ 9 ! preamble ( ! pat5t3       ,?is 
inv5tion relates to mat]ial work+       
ma*9es1 &      p>ticul>ly to ma*9es su* 

z hob gr9d]s & ! l1 :]e9      ! "w is   
reciprocat$ ?r\gh ! ag5cy ( a lead      
screw4       ,9 ! manufacture ( hobs x  
is common practice to employ ! same     
ma*9e = gr9d+ hobs ( v>i$ diamet]s1 & 9 
ord] to      employ su* a ma*9e 9 ?is   
mann] ! pit* ( ! lead screw1      !re(1 
:i* actuates ! "w c>ri]1 mu/ con=m to ! 
axial      pit* ( ! hob to be gr\nd4    
,?is w be readily app>5t :5      x is   
und]/ood t ! helix angles ( hobs v>y 9  
accordance      ) _! diamet]s &1        
consequ5tly1 ! diff]5ce betwe5 !        
normal pit* & ! axial pit* correspond+ly
 v>ies4 ,:ile !      requirem5t = !     
normal pit* may be ! same = hobs (      
diff]5t diamet]s1 x is necess>y to *ange
 ! axial pit* 9      accordance ) a     
*ange 9 ! hob diamet]1 & ?is axial pit* 
( ! hob is equal to ! pit* ( ! lead     
screw :i* actuates      ! "w c>ri] 9    
gr9d+ ma*9es h]et(ore us$4 ,h5ce1 9     
ord] to adapt su* ma*9es to cov] a wide 
range ( leads1 x is      necess>y to    
provide a l>ge numb] ( int]*angeable    

lead screws      & obvi\sly ?is         
repres5ts a l>ge inve/m5t1 & !          
int]*ang+ ( ^! screws requires !        
exp5diture (      consid]able "t 9 sett+
 up ! ma*9e = ea* job4  ,?read-gr9d+    
ma*9es 7 be+ design$ concurr5t ) !      
developm5t ( hob-gr9d+ ma*9es4 ,_m 7    
entirely conc]n$ ) features peculi> to !
 problems ( :eel-dress+ & to automatic  
*>act]i/ics4 ,an inv5tion to embody !   
use ( a ma/] screw & conc]n$ ) !        
precision gr9d+ ( worm ?reads1 = use 9  
ge>+1 0 pat5t$ by ,fr$]ick ,a4 ,w>d 9   
?is era4#h ,t "p ( ! inv5tion p]ta9+ to 
! use ( a ma/] screw1 a rot>y "w hold]  
m\nt$ on said c>riage & provid$ ) a     
driv+ sp9dle1 an ex*angeable ma/] screw 
& /ation>y nut deta*ably secur$ to said 
sp9dle & head1444 is %[n 9 figure #bc4  
,illu/ration3 ,figure #bc4--;,,details  
,,( ,a ,,"w ,,sp9dle ,,) ,,"w1 %[+ ! use
 ( a ma/] lead screw to control ! pit* (
 a precision worm ?read be+ gr\nd4 ,f ! 
#aicc ,u4,s4 pat5t #ahiifed1 ( ,f4 ,a4  
,w>d's worm-gr9d+ ma*9e4  ,ma*9es       

embody+ ! pr9ciple ( ! ma/] lead screw  
are f\nd 9 con/ant use by indu/ry at !  
pres5t "t = specializ$ application4     
,:5ev] te*nological *anges aga9 reop5 ! 
topic ( ?read-cutt+ to a new degree (   
accuracy or call = a reevaluation (     
popul> me?ods = any o!r reason1 we may  
expect to see ano!r resurg5ce ( !       
ma/]-screw me?od1 = no o!r design       
elim9ates s _m v>iables or re/s on su*  
firm & fundam5tal natural pr9ciples z ! 
ma*9e ( ,das mittelalt]li*e ,hausbu* (  
#adhc1 ! e>lie/ su* ma*9e n[ kn[n4      
,,footnotes3  #a ,,jacques ,,besson1    
,des in/rum5ts ma?matiques1 et          
m*aniques1 s]vants  l'intellig5ce de    
plusi]s *oses difficiles1  necessaires  
t\tes rpubliques1 #a/ ed4 7,orleans1    
#aefi74 ,also available 9 lat] editions 
9 ,fr5*1 ,g]man1 & ,spani%4  #b ,j4     
,,fo/] ,,petree1 introduction1 ,h5ry    
,maudslay1 #agga-ahca1 & ,maudslay ,sons
 & ,field1 ,ltd4 7,london3 ,! ,maudslay 
,society1 #aidi74  #c ,am]ican ,ma*9i/  
7,septemb] #bh1 #aiaf71 vol4 #de1 no4   

#ac1 pp4 #ebi-eca4  #d ,u4,s4 pat5t     
#ajchc issu$ to ,joseph ,nason ( ,new   
,york1 ,janu>y #c1 #ahed4  #e ,u4,s4    
pat5t #bicicj issu$ to ,*>les ,v&] ,wo]d
 ( ,wal?am1 ,massa*usetts1 ,febru>y #ai1
 #ahhd4  #f ,u4,s4 pat5t #ahgdeib1 fil$ 
,june #h1 #aibi1 issu$ to ,c4 ,g4 ,olson
 ( ,*icago1 ,ill9ois1 ,augu/ #cj1 #aicb1
 & assign$ to ! ,ill9ois ,tool ,works1  
also ( ,*icago4  #g ,u4,s4 pat5t        
#aijaibf1 fil$ ,febru>y #af1 #aibh1     
issu$ to ,c4 ,g4 ,olson ( ,*icago1      
,ill9ois1 ,m>* #ba1 #aicc1 & assign$ to 
! ,ill9ois ,tool ,works1 also ( ,*icago4
  #h ,u4,s4 pat5t #ahiifed1 fil$ ,augu/ 
#ca1 #aica1 issu$ to ,f4 ,a4 ,w>d (     
,detroit1 ,mi*igan1 ,febru>y #bh1 #aicc1
 & assign$ to ! ,ge> ,gr9d+ ,company (  
,detroit1 ,mi*igan4         99       99 
99       99       99  ,u4,s4 ,,gov]nm5t 
,,pr9t+ ,,(fice3 #aifd  ,= sale by !    
,sup]9t5d5t ( ,docum5ts1 ,u4,s4         
,gov]nm5t ,pr9t+ ,(fice ,wa%+ton1 ,d4,c4
 #bjdjb--,price #bj c5ts   ,,index      
,besson1 ,jacques1 #ajg     ,d\glas1 ,w4

  ,b41 ,company1 #aac     ,maudslay1    
,h5ry1 #ajf1 #aac     ,nason1 ,joseph1  
#aad    ,nor?1 ,simeon1 arms factory1   
#aad     ,olson1 ,c>l ,g41 #aah     ,v&]
 ,wo]d1 ,*>les1 #aaf1 #aag     ,w>d1    
,fr$]ick ,a41 #abj    ,wets*gi1         
,emanuel1 #ajh    ,wets*gi1 ,manuel1    
#ajh1 #aaa    ,:itney arms factory1 #aad
    ,wilk9son1 ,david1 #aac