152 mOF. ATTFrELD — POISONS NOT ALWAYS POISONS. 



hid itself amongst the papers. The salt, with the exception of a thin shell, had 

 been completely eaten by the insect. Never having met with or lieard of a 

 parallel circumstance, I was induced to investigate more minutely, with tlie view 

 of discovering if I might not have been deceived. On recovering the spider I 

 found it was of the species Araiiea scenica. 



" lie had assumed a perfectly black colour; was, on being approached or dis- 

 turbed, remarkably brisk in his motions ; but at other times would drag his legs 

 after him in a peculiarly sluggish manner. Having cleaned the box, I deposited 

 the insect in it, with a lump of nearly two ounces of sulphate of zinc. In about 

 ten weeks he had pierced this also ; and, as usual, had produced a considerable 

 portion of the powder. I then deposited other metallic salts, as sulphates of iron, 

 lead, and copper, muriates of lead and mercury, and nitrates of copper and silver, 

 with the sulphate of zinc in the box ; but the spider did not leave the latter, nor 

 did he touch cither of the other salts, though I removed the sulphate of zinc for 

 a time from the box. Being thus satisfied of the fact, I endeavom-ed to ascertain 

 if the salt had undergone any chemical change in passing through the spider. I 

 caused him to fast two days, then deposited him in a clean box, with 200 grains 

 of sulphate of zinc ; and when I perceived he had nearly eaten half of it, I 

 carefully weighed the remainder with the powdery substance. It weighed 170 

 grains ; here was a loss of nearly thirty per cent. This, however, might be in 

 part water. I therefore collected sixty grains of the powder, on which I poured 

 six ounces of boiling water. A considerable part remained undissolved, though 

 frequently agitated, during two days. Ten drops of sulphuric acid were then 

 added, and the whole was dissolved. It seems probable, therefore, that the sul- 

 phate of zinc has been deprived of part of its acid in passing through the spider. 



" The insect at this time seems perfectly healthy, having eaten nearly four 

 ounces of the salt in about six months." 



This is a matter which a chemist could understand, if it could 

 be understood at all. But I cannot conceive that an animal like a 

 spider can exist on sulphate of zinc, and therefore I say you must 

 take this account for what it is worth. At the same time, I should 

 like to remind you that the atoms of the food we eat do their work 

 in a physical manner. We cannot destroy anything any more than 

 we can create anything, and if we take food, the molecules and 

 atoms forming that food enable us to live and move, but then they 

 pass away unaltered in total weight : it is during the alteration of 

 form only that food does this wonderful work for us. As a matter 

 of fact, it is animal and vegetable matter chiefly which enables us 

 to live on and labour, but I do not suppose that we should look 

 upon it as absolutely impossible that mineral matter should aid in 

 the same kind of work under some circumstances, at all events for 

 some animals. What I cannot conceive is that mineral matter 

 alone, or even mineral matter and water, should do such work, 

 unaided by animal or vegetable matter. 



A peculiar case of poisoning was brought to my notice by a 

 friend residing in Malta. He sent to me a cutting from the 

 'Malta Times,' giving the following account. 



""Wholesale Poisoning by Milk. — On Sunday morning last most of the 

 occupants of two of the first-rate hotels in Yaletta, the Imperial and Morrell's, 

 were seized with symptoms of virulent cholera. In the former hotel not less 

 than twelve persons, including the landlord and servants, and in the latter seven 

 persons, were attacked. Medical assistance was immediately procured, and appro- 

 priate remedies were applied. We are happy to state that the patients are now 

 doing well, although for a time the violence of the symptoms led to apprehensions 

 of a fatal result in many of the cases. From inquiries made it appears that all 



