1871 •] Mr. F. Galton's Experiments in Pangenesis. 



407 



they are not fit to be operated on. The next essential point is an operating- 

 table, with ample and proper apparatus for holding the rabbits easily but 

 rigidly. It is most improper to subject a helpless animal to an operation 

 without taking every precaution for its success, so as to minimize the ne- 

 cessity for operating. The chief hindrances to success are, entanglement 

 of instruments, or the breaking loose of blood-vessels, both owing to an un- 

 expected start ; also an animal will struggle violently, and become terrified 

 if he is loosely held, hoping to get away, whilst if he is firmly secured he 

 lies as though magnetized, without signs of fear or discomfort, and with 

 his pulse and breathing perfectly normal. I regret extremely that, although 

 I took pains to inquire, I did not at first hear of Czermak's recently devised 

 apparatus for holding the head. I began by the old plan of putting the 

 animals in a bag and holding them, which was very unsatisfactory. Then 

 I devised a plan of my own, which was good, but inferior to Czermak's, 

 and I therefore abstain from describing it. The latter, with recent modi- 

 fications, can now be obtained at Mr. Hawkesley's, 4 Blenheim Street, 

 Bond Street, London, to whom, I should say, I have been greatly indebted 

 for the care and thought he gave to successive and very numerous modi- 

 fications of my instruments (far more numerous than I care to describe). 

 A drawing of Czermak's apparatus will be found in the 'Berichte der 

 K. Sachs. Gesellschaft der Wissenschaften zu Leipzig,' 1867, p. 212. 



For injections, I used a five-drachm ebonite syringe, whose stem was 

 boldly graduated to drachms. The canula (to be inserted into the vein) was 

 screwed into a light stopcock. This was 

 filled with water, which, so long as the cock 

 was closed, did not run out for want of a 

 vent-hole. When it was thrust in the vein 

 and the vein was tied round it, I held the 

 syringe full of blood near the open end of the 

 stopcock, drove out all air by allowing a few 

 drops of blood to fall into its mouth, then 

 pushed its nozzle firmly in, opened the cock 

 and began to inject, steadily and slowly, at 

 the rate of about one drachm in twenty 

 seconds. When the syringe was emptied, 

 I turned the stopcock, withdrew it, rapidly 

 filled it, emptied it and again filled it with warm water, and returning to 

 the canula with the same precautions as before, I threw in about J drachm, 

 to wash the blood out of the canula and adjacent vein. I do not think 

 I lost more than three (or perhaps four) rabbits by injecting air, although 

 the removals and replacements of the syringe were very numerous, often 

 ten times in a single operation of the w kind. 



My apparatus consisted of a zinc warm-water bath, represented on the left 

 of the diagram (p. 408) ; the vessels drawn to the right of it fitted into holes 

 in its lid, as indicated by the letters. A is the basin to catch the supply blood ; 



