NATURAL PHILOSOPHY. 127 



" An objection has been raised to the Morse registering fillet, that it 

 is too voluminous for the quantity of matter recorded. This objection, 

 and that of expensiveness, apply with more force to the metallic cylin- 

 der, however accurate be its indications. To remedy this evil Mr. 

 Saxton has contrived a sheet of paper which incloses the cylinder and 

 lasts for about two hours of constant work. The sheets and register- 

 ing fillets now submitted for the inspection of the Association con- 

 tain the comparison of the printed record of the culmination of the 

 stars in the Dolphin. The Saxton sheet, the chemical fillet, and the 

 Morse fillet, are triplicate records of the same identical star-signals. 

 The result of the reading, as far as experiments have been made, is, 

 that all kinds of registers at the same place read alike. It is worthy 

 of remark, that these registers contain the printed record of the tran- 

 sits of both components of the double star Gamma Delphini, printed 

 with ease on each of the forty-five wires of the Wurdemann's dia- 

 phragm, making ninety imprints in a culmination. From my experi- 

 ence in printing the transit of this pair of double stars, I am led to 

 the conclusion, that four stars forming a quadruple star, when at prop- 

 er distance, may all be printed at the time of their transit over a dia- 

 phragm of fifty wires, making two hundred imprints for one transit, 

 a rapidity of playing on the key far below that of good execution on 

 the piano. 



" Of the different kinds of registers I prefer the sheet of Mr. Saxton. 

 One sheet filled on both sides, or two pages, will contain an ordinary 

 night's work. A year's work will make a book of some three hun- 

 dred pages, on the margin of which may be entered the ordinary re- 

 marks for an observing-book, relative to the state of the level and 

 meteorological instruments, name of stars observed, and instrumental 

 deviations. If folded up, or bound and put away for a century, the 

 reduction of the work will then be as easy as at first. In fact, we 

 may, with the metallic cylinder, electrotype the plate ; or, using cop- 

 per, we may print from it without. And, in the case of the paper 

 sheet, instead of Saxton's graver, with Indian ink, we may employ 

 a pen, with lithographic ink, and multiply copies at pleasure, when- 

 ever we choose. When we consider the compactness of the register 

 on Saxton's sheet, we may perhaps find that the publication of transit 

 observations will best be made by the lithographic process, applied to 

 the printed telegraph sheets ; thus giving to the world the printed record 

 with all the accuracy of a Daguerreotype. The registering fillet now 

 exhibited to the Association contains the culmination of both limbs of 

 the moon, printed by myself, on the 3rd of August last, on 35 wires 

 of the diaphragm. By the mean of the results, the probable error of 

 the imprint of a transit of a single limb over a single wire is the six- 

 teenth of a second; whereas, in 1846, with the great Washington 

 Equatorial, and a power of 300, I found that, with the old method, 

 my probable error, by G6 trials, was twice as great, namely, the 

 eighth of a second. Thus it appears that the measure of precision 

 is twice, and the weight four times, as great, in the new method, as 

 in the old. No labor of training for the work is needed. 



" A hundred wires is a high estimate for a night's work of an obser- 



