Other operators, following the advice of Eckstein, who advised the employment of “Hart paraffin” of high melting point liquefied by heat, raised the objection that the metal needle became so easily obstructed by the rapid setting of the paraffin in its distal end that the great force necessary to eject the contents of the syringe usually resulted in a breakage of the glass barrel in the hands of the operator, or, as in some types of the syringe, a separation of needle and syringe at the point where the former was slipped upon the ground point of the latter, with the annoyance of the paraffin squirting over the faces of both patient and operator. Eckstein tells us how to overcome the first difficulty with this same style of syringe as used by him. He covers the syringe with a rubber insulating sleeve and draws several drops of hot, sterilized water into the needle to overcome the plugging up of the latter; an illustration of his syringe has been shown on page 232. Mention has also been made of the various methods used to overcome this difficulty by other operators. It was presently found that such an instrument was not only impractical, but also a detriment to procuring desirable results, the paraffin solution shooting out suddenly, in some instances causing hyperinjection, and at other times emerging so slowly that it required unusual force on the part of the operator—a painful procedure for delicate hands, inasmuch as the fingers only can be applied to operate the instrument. With the object of overcoming this uncertainty of the amount of the injection and the unnecessary exertion to inject any given quantity, as well as to establish enough _vice à tergo_ to keep the needle free from plugging up with cooling paraffin, various operators devised instruments, all having practically similar points of mechanical merit and usefulness. The required necessities being to invent a syringe which would have a known capacity, a piston under control of the operator at all times, and metallic needles of proper lumen, to prevent the solidification of the liquid paraffin, screwed to the syringe to prevent loosening. With the object of overcoming these difficulties the author devised a syringe which was made for him by Tiemann & Co., early in 1902. He begs to introduce the same here, as a type similar to which most operators have built their special instrument.