invertebrata,) still greater. To these I have added some made upon plants. I am aware it may be objected that the effects of the acid upon animals is different from what it is upon man. To this objection I attach little value, as from what I have seen of the effects of the acid upon warm and cold-blooded animals, as compared with what I witnessed in the two cases of poisoning which I have seen in men, and the accounts of other observers, as well as from analogy, I believe the action is essentially the same upon all, and that inferences drawn from experiments upon animals, of which the dog, from his not very dissimilar organization and diet is, perhaps, as favourable, if not more so, than most others, if fairly deduced, are in their application to man to be relied upon.
I shall, in the first place, put before the reader as concise an account as possible of many of the experiments, from which he can draw his own deductions. I shall then venture to add the conclusions which I have drawn from them. It may be stated, that during each experiment an assistant was present, who, like myself, was provided with a watch. He was placed at a table with pens and paper, so that each observation was recorded at the moment it was made. This will account for some of the expressions used. Some may think the time is stated with unnecessary precision and minuteness, but it must be borne in mind that the exact period at which effects are produced is not only one upon which there is the greatest contradiction, but which is one of the most important. In all cases where the strength of the acid employed is not mentioned, it was Scheele's. This I selected as that most generally met with in this country, and consequently of the strength most likely to be employed in poisonous doses by the public. It also is of a convenient degree of dilution. The acid used in many of the experiments was obtained from Allen and Co., Plough Court; in the remainder, from Gale, Baker, and Co., Bouverie street. In both cases it was recent, as I am informed by both was of the exact strength of Scheele's acid, viz., five per cent. of real acid, and I did not observe any difference in the effects. The strong acid I made by distilling at a low heat ten drachms of Scheele's acid, until two drachms had passed over into a receiver kept constantly as cold as possible; it, therefore, should be equal to twenty-five per cent. of real acid, or four drops to one of anhydrous
