In this class also we must place tanneries, glueworks, and size factories, a visit to which is a severe trial for any one unaccustomed to them. Dyeworks, likewise, by reason of the organic sulphur compounds they disseminate through the spongy air, are unpleasant neighbours. In cotton mills, also, the sizing-rooms are objectionable, and here, curiously enough, the operatives do not seem to become accustomed to the smell, as it is insinuatingly rather than bluntly offensive, and grows worse with use. So much so, indeed, that but few of the girls, I am told, are able to remain in that particular occupation for more than a few weeks at a time. At this stage, albeit early in our disquisition, we may appropriately turn to consider the curious fact that of all our senses that of smell is perhaps the most easily exhausted. The olfactory organ, under the continued stimulation of one particular odour, quite quickly becomes insensitive to it. Perhaps this is the reason, or one of the reasons, why reform was so long delayed. There are, however, in this respect great differences between odours. With some the smell is lost in a few seconds, while with others we continue to be aware of it for a much longer time. Curiously enough, odours seem, in this matter, to follow the general law of the feelings in that the pleasant are lost sooner than the unpleasant. It is the first breath of the rose that makes the fullest appeal, when the whole being becomes for a moment suffused with the loveliest of all perfumes. But only for a moment. All too soon the door of heaven closes and the richness thins away into the common airs of this our lower world. On the other hand, the aversion we all feel from substances like iodoform, or, what is worse, scatol, owes not the least part of its strength to the fact that both of those vile smells are very persistent. As was once said to a surgeon applying iodoform to a wound in a patient’s nose: “This patient will certainly visit you again, sir, but—it will not be to consult you!” To this more or less rapid exhaustion of the sense is due the merciful dispensation that no one is aware of his own particular aura. We are only cognisant of odours that are strange to us. The Chinese and Japanese find the neighbourhood of Europeans highly objectionable, and we return the compliment. It is the stranger to the Island who remarks the “very ancient and fish-like smell.”