Greek, πυουλκός.
Galen (xi. 125) says:
‘In cases of sinus he uses a tube of bronze or horn with a straight bore, or otherwise the instrument called the pus extractor (πυουλκόν), which has a wide bore. But if you inject rosaceum into the former (i. e. tube of bronze, &c.) it will not pass through the syringe (πυουλκῷ), so that in that case a pipe of wide bore is to be fixed to a sow’s bladder.’
This passage shows that the pyulcus differed in principle from the syringe formed by fixing a bladder on a tube. Hero (De Spiritalibus, c. 57) shows that it was a syringe formed of a cylinder of metal with a well-fitting plunger.
Hero says:
‘And the instrument called pyulcus works on the same principle.
‘For a long tube AB is made, to which let there be fitted another CD, and let C, the end of it, be closed by a plate. At D let it have a handle EF, and let the mouth of the tube AB at A be blocked by a plate furnished with a slender syringe GH, perforated.
‘When therefore we wish to draw out pus, applying the extreme mouth H of the little syringe to the place in which the pus is, by the handle we draw the tube CD outward, and the space which is in the tube being emptied something else is of necessity drawn in, and since there is no other space than the mouth of the tube the liquid at and near it must of necessity be drawn into it.
‘Again when we wish to inject some liquid we put it into the tube AB and taking hold of EF and pressing in the tube CD we press out as much as we think necessary.’
Note that Hero’s description does not tally with the drawings which accompany the edition of his works which we possess ([Pl. XXXVIII, figs. 3, 4, 5]). These show an instrument with a piston formed by a plug at the end of a rod, whereas Hero says the piston is to be formed of a second tube fitting inside the first. This is interesting, because it is much easier to get a well-fitting piston in this way than in the other; and this principle has been reverted to in many of our best hypodermic syringes and in some of the best air pumps, such as Edwards’s.