3£0 Mr Barlow cm the Practical Construction 
TABLE — Continued. 
1 st Surface . 
4 th Surface . 
Dipersive 
Radius to 
Radius to 
Ratios. 
Indices 
Correction, 
Correction, 
Indices 
Correction, 
Correction, 
1-524 
1-585 
Plate Index. 
Flint Index. 
1-585 
Plate Index. 
Flint Index. 
«590 
6-7089 
+ 6-86 
+ *274 
14-3417 
4 - 108-54 
— 55-33 
•591 
6-7087 
+ 6-85 
4 - *284 
14-3369 
4 - 108-74 
—. 55-45 
•592 
6-7085 
4 - 6-84 
4 - *294 
14-3321 
+ 108-94 
— 55-53 
•593 
6-7083 
+ 6- 83 
4 - -304 
14-3273 
+ 109-13 
— 55-70 
•594 
6-7081 
4 - 6-82 
4 - -313 
14-3225 
4 - 109-32 
— 55-83 
•595 
6-7089 
4 - 6-81 
4 - -322 
14-3177 
+ 109-51 
— 55-95 
•596 
6-7079 
+ 6-80 
4 - -332 
14-3129 
+ 109-71 
— 56-08 
•597 
6-7076 
4 - 6-79 
4 - *342 
14-3081 
4 - 109-90 
— 56-20 
•598 
6-7075 
+ 6-78 
4 - *352 
14-3033 
4 - 110-09 
— 56-33 
•599 
6-7073 
+ 6-77 
4 - *361 
14-2985 
+ 110-29 
— 56-46 
! -600 
6-7071 
4 - 6-7 6 
4 - *370 
14-2937 
4 - 110-49 
— 56-59 
•601 
6-7069 
+ 6-73 
4 - -388 
14-2792 
4 - 110-60 
— 56-72 
•602 
6-7073 
4 - 6-71 
4 - *406 
14-2647 
4 - 110-71 
— 56-85 
•603 
6-7077 
4 - 6-69 
4 - -424 
14-2502 
+ 110-83 
— 56-99 
•604 
6-7086 
4 - 6 * 6 7 
4 - *442 
14-2357 
+ 110-94 
— 57*12 
•605 
6-7091 
4 - 6-64 
4 - *460 
14-2212 
+ 111-05 
— 57-25 
•60 6 
6-7096 
4 - 6-62 
4 - *478 
14-2067 
4 - 11 M 7 
— 57-39 
•607 
6-7101 
4 - 6-60 
4 - *495 
14-1922 
+ 111*28 
— 57-52 
•608 
6-7106 
- 1 - 6-58 
4 - *512 
14-1777 
4 111-39 
— 57-65 
•609 
6-7111 
4 - 6-55 
4 - -529 
14-1632 
+ 111-51 
— 57-79 
•610 
6-7116 
4 - 6-53 
4 - *546 
14-1487 
+ 111-62 
— 57-92 
•611 
6-7121 
4 - 6.51 
4 - -564 
14-1342 
+ HI -73 
— 5805 
•612 
6-7126 
4 - 6-49 
4 - -582 
14-1197 
4 - 111-85 
— 58-19 
•613 
6-7131 
4 - 6-46 
4 - *600 
14-1052 
4 - 111-96 
— 58-32 
•614 
6-7136 
4 - 6-44 
4 - *618 
14-0907 
+ 112-07 
— 58-45 
•615 
6-7141 
4 - 6-42 
4 - • 636 
14-0762 
4 - 112-19 
— 58-59 
•616 
6-7146 
4 - 6-40 
4 - *654 
14-0617 
+ 112-30 
— 58-72 
•617 
6-7151 
4 - 6- 37 
4 - *671 
14-0472 
4 - 112-41 
— 58-85 
•618 
6-7156 
4 - 6-35 
4 - *688 
14-0327 
+ 112-53 
— 58.99 
•619 
6-7161 
4 - 6-33 
4 - *705 
14-0182 
4 - 112-64 
— 59-12 
•620 
6-7166 
4 - 6-31 
4 - *722 
14-0037 
4 - 112-75 
— 59-25 
•621 
6-7171 
4 - 6-28 
4 - *740 
13-9892 
4 - 112-87 
— 59-39 
•822 
6-7176 
4 - 6-26 
4 - -758 
13-9747 
4 - 112-98 
— 59-52 
•623 
6*7181 
4 - 6- 24 
4 - -77 6 
13-9602 
4 - 11309 
— 59-65 
•624 
6-7186 
4 - 6-22 
4 - *794 
13-9457 
+ 113-21 
— 59-79 
’625 
6-7191 
4 - 6-19 
4 - -812 
13-9312 
4 - 113-22 
— 59-92 
•626 
6-7196 
4 - 6-17 
4 - -830 
13-9167 
+ 113-43 
— 60-05 
•627 
6-7201 
4 - 6-15 
4 - -847 
13-9022 
4 * 113-55 
— 60-19 
•628 
6-7206 
4 - 6 -13 
4 - -864 
19-8877 
4 - 113-66 
- r - 60-32 
•629 
6-7211 
4 - 6-10 
4 - *881 
13-8733 
4 - 113-77 
— 60-45 
•630 
6-7216 
4 - 6- 08 
4 - -898 
13-8589 
4 - 113-89 
— 60-59 
•631 
6-7221 
4 - 6-06 
4 - *916 
13-8445 
4 - 114-00 
— 60-72 
•632 
6-7226 
4 - 6-04 
4 - *934 
13-8301 
4 - 114-11 
— 60-85 
•633 
6-7231 
4 - 6-01 
4 - *952 
13-8157 
4 - 114-23 
— 60-99 
•634 
6-7236 
4 - 5-99 
4 - -970 
13-8013 
4 - 114-34 
— 61-12 
•635 
6-7241 
4 - 5-97 
4 - -988 
13-7869 
4 - 114-45 
— 61-25 
•636 
6-7246 
4 - 5-95 
4 - 1-006 
13-7725 
+ 114-57 
- 61-39 
•637 
6-7251 
4 - 5.92 
4 - 1-023 
13-7581 
4 - 114-68 
— 61-52 
•638 
6*7256 
4 - 5-89 
4 - 1-040 
13-7437 
4 - 114-79 
- 61-65 
•639 
6-7261 
4 - 5-87 
4 - 1-057 
13-7393 
4 - 114-91 
— 61-79 
•640 
6-7266 
4 - 5-85 
4 - 1-074 
13-7249 
4 - 115-02 
— 61-92 
.641 
6-7271 
4 - 5-83 
4 - 1*092 
13-7105 
4 - 115-13 
— 62-05 
•642 
6-7276 
-h 5-80 
4 - 1*110 
13-6961 
+ 115-25 
— 62-19 
•643 
6-7281 
+ 5-78 
4 - M 28 
13-6817 
4 - 115-36 
— 62-32 
•644 
6-7286 
4 - 5 - 7 6 
4 1-146 
13-6673 
4 - 115*47 
_ 62-45 
