PROCEEDINGS OF THE POLYTECHNIC ASSOCIATION. 479 



Samuel D. Tillman, Esq.: 



Sir — I beg to express my gratitude for j^onr invitation to attend the next 

 meeting" of your Association on Thursday the 22d. Unfortunately I find it 

 impossible to comply with it, as according to a previous engagement, I am 

 to start with the greatest part of my officers on an excursion to Niagara . 

 Falls. 



I feel a deep regret at missing the opportunity you kindly offer me, to 

 acquire valuable information on a subject so important in the present war- 

 fare. 



Not being able to join you, I expect you will kindly extend your enlight- 

 ened welcome to Captain Bootakoff of the Oslaba, the senior captain of 

 the Squadron, and to such of our officers whom duty will permit to accom- 

 pany him. 



^ With great respect, yours, 



S. LESSOFFSKY. 

 Bear Admiral, Imperial Eussian Navy. 



Flagship Alexaxder Neosky, the 9 | 21st of October, 1863. 



Capt. Bootakoff and several other officers from the Russian Fleet* here 

 entered the room and after a cordial welcome from the Chairman were con- 

 ducted to seats reserved for them. 



The Elliptic Sewing Machine. 



The miscellaneous business commenced with the exhibition of this 

 machine from A. H. Saplee, 531 Broadway. Miss L. O'ConnoU operated 

 the machine, and explained very clearly its several parts. The principal 

 improvements in this invention are the elliptic hook and stationary bobbin- 

 bolder, made by Mr. Blodgett, of Philadelphia. By aid of the annexed 

 illustrations and description, the working of the machine, which uses two 

 threads^ will be readily understood. Figure 1 is a view of the machine on 

 the table. Fig. 2 is an enlarged view of the machine removed from the 

 table. Fig. 3 shows it with cloth-plate removed. The spool of thread is 

 placed in the spindle 38; the end is passed under the drag-bar 39, which has 

 in it a spring for the purpose of holding the thread firmly as it passes around 

 the tension pulley 40, thence through eyelets 34, 34-35, and through a needle- 

 eye from left to right. The under thread is wound on the metallic bobbin 

 15, by the spindle V, under the point of the table. When filled, the bobbin 

 is placed in the bobbin-holder 10, by slightly unscrewing the large nut 11. 

 Particular attentiim is called to the simple and ingenious device of the hook 

 5 and the bobbin-holder 10. This bobbin-holder being stationary, the drag 

 or strain on the under thread is entirely avoided, thereby requiring only 

 one-half the tension necessary in all other machines, The advantage 

 gained is elasticity of stitch. The screw 14 is fin- the purpose of pushing 

 the holder slightl}- apart, to give the heaviest flax thread room to pass 

 freely around the bobbin without the slightest wear. The spring 12-13 is 

 used to produce the tension on the bobbin-thread, and is only employed 

 when linen thread is used. This adapts the machine to a great range of 

 work. Fig. 4 is a front sectional view of the entire mechanism: 5 being 

 the elliptic hook; 18-19, the feed-bar; H, the leather band in a grooved pul- 

 ley, communicating with the treadles. The cam It gives motion to the 



