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Congress, 2d Session, Senate, Doc. No. 225. Washington, 1842. 8vo, 
26 pp. and 3 folding plates. 
58.—Bacux, A. D., & McCutton, R. 8. Reports from the Secretary of 
the Treasury, of scientific investigations in relation to sugar and hydrome- 
ters, made, under the superintendence of Prof. A. D. Bache, by Prof. R. S. 
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59.—BacurE; Prof. ALEXANDER D. Report to the Treasury Department 
on the progress of the work of constructing standards of weights and measures 
for the custom-houses, and balances for the States, and in supplying stand- 
ard hydrometers to the custom-houses, from 1 Jan., 1848, to 31 Dec., 1856. 
34th Congress, 8d Session, Senate, Ex. Doc, No. 27. Washington, 1857. 
8vo, 218 pp. with 6 folding plates. (Contains descriptions of yard dividing 
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60.—RocrErs; Prof. W. A. On the present state of the question of stand- 
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61.—RogeErs; Prof. W. A. On two forms of comparators for measures 
of length. 8vo, 12 pp. American Quarterly Microscopical Journal, April, 
1879. 
62.—RogeErs; Prof. Wm. A. Studies in metrology. 5 Plates. (Con- 
tains description of the Rogers-Bond universal comparator.) Proceed. 
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63.—Rogers; Prof. W. A. An examination of the standards of length 
constructed by the Société Génevoise. Proceed. Amer. Acad. of Arts and 
Sciences, 1884—’5. Vol. 20, pp. 379-3889. 8vo. 
‘ 
64.—Rocrrs; Prof. W. A. A study of the centimeter marked ‘A,” 
prepared by the U.S. Bureau of Weights and Measures for the Committee 
on Micrometry. 8vo,23 pp. Proc. Amer. Society of Microscopists. Vol. 
82, p. 184. 
65 —Rogers; Prof. Wm. A. Ona practical solution of the perfect screw 
problem. 8vo,44 pp. Trans. Amer. Soc. of Mechanical Engineers. Vol. 5. 
66.—Roarrs; Prof. W. A. A critical study of the action of a diamond 
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67.—Travaux et mémoires du Bureau International des Poids et Mesures, 
publiés sous ’autorité du Comité International, par le Directeur du Bureau. 
Paris. 4to. Tome 1, 1881, 391 pp.; T. 2, 1883, 413 pp.; T. 3, 1884, $48 
pp.; T. 4, 1885, 421 pp.; T. 5, 1886, 416 pp. 
