458 
LIEUT.-COL. A. E. CLAEKE ON STANDAEDS OE LENGTH. 
Vienna Toise. 
The toise marked on the Pulkowa klafter was compared twelve times with the Ordnance 
Survey toise in September 1867 at temperatures from 58° to 59°, and nine times in 
December of the same year, the temperature ranging from 39° to 42°. 
The observations being reduced by the method of least squares lead to the following 
result, both bars being at the temperature of 61 0, 25, 
T V =T 0 — 362-73 + 0-27, 
where T v is the length of the Vienna toise, and T 0 that of the Ordnance toise. 
Now the length of the T 0 at 61 0, 25 is, as given at page 280 of the ‘ Comparisons of 
Standards,’ 
T 0 =2-13166458g. 
Hence the length of the toise on the Vienna klafter 
T v =2 -131 30185^. 
If we compare this with the length of the Prussian toise T I0 , which (Comp. Stand, 
page 280) was found by comparisons to be 
T 10 =2T3150911|3, 
it appears that the Vienna copy is shorter than the Prussian by 207*26 ; that is, 
T V =T 10 — 207-26. 
The lengths obtained from these two toises by M. Struve, see ‘ Arc du Meridien . . . 
I860,’ vol. i. p. lxxii, are (he calls the bar B') 
T 10 =863 1 -99914, 
T v = 863-91726 ; 
and the difference of these expressed in millionths of a yard is 
T V =T 10 — 202-00. 
The agreement of this with the Southampton results is not very satisfactory. 
The ratio of the klafter to the toise as both marked on the Pulkowa klafter is, accord- 
ing to the observations we have recorded, 
2-07403629 
24 3130185 
"973130850. 
The same ratio, according to the measures of M. Struve, is 
840-70342 
863-91726 
=•973129556. 
The same ratio as obtained from the observations of M. Stampfer is (see ‘ Vergleiclr 
ungen der Wiener Masse See . ,’ page 15) 
0-97313204. 
The ratio as determined in the observations at Southampton is therefore intermediate 
between these. 
