Of carelessness with gas in shops and warehouses, or with candles near bedroom curtains, muslin dresses, or linen airing before the fire, we need not speak, as the dangers are too obvious by the results; nor of carelessness with lucifer-matches; nor the very common practice of raking out the fire at night from the grate (where it would be safe) down upon the hearth, and leaving the hot embers, which perhaps ignite by the air of the closing door, as the careful person retires to bed. Carelessness with a cigar or pipe is also an obvious cause. Working men often put their pipes, half-extinguished, or alive at the bottom of the bowl, into their jacket-pocket at night; and then hang up the jacket, and go to bed. Children, also, being left alone, near a fire, may generally be expected to play with fire, either because it is beautiful, or because the play is interdicted. With respect to ‘sparks,’ that a house should take fire, had always been regarded by us with no small degree of scepticism. A gentleman of our acquaintance carried his disbelief much further. Sitting with a party of sporting friends round a winter’s fire, and these dangers being the subject of conversation, he offered to empty the whole contents of the grate on the carpet in the middle of the room—_he_ to pay all expenses if the house took fire; his opponent simply to pay for the carpet and the charred floor. They were all to sit round, and watch the result. It was agreed. ‘Now,’ said a friend, ‘I will bet you _ten_ to one this house will take fire, provided we all go out of the room, lock the door, and leave the house.’ The other would not venture on this. Mr. Braidwood’s speculation on the question of sparks, in reply to our doubts, is very curious and practical. He estimated the number of houses in London at 300,000. Allowing two _domestic_ fires to each house, we have 600,000 in the day; and these multiplied by 7, give 4,200,000 in a week. That one spark, therefore, from 4,200,000 fires should fly out upon some materials easy to ignite, once in a week, is far from difficult to credit; and this would fully bear out the number on the list that are declared to have occurred from this cause. The number of fires and alarms of fire that occurred in London during the fifteen years ending in 1847, present a continual _increase_. In 1833 they amounted to 458; in 1834, to 482; and so on, down to 1847, when they amounted to 836. This gives a total of 9662 fires during the fifteen years. The average of this is 644. We next find that in 1848 the number of fires amounted to 805; showing an _increase_ beyond the previous year of 161. In 1849 the number amounted to 838, being an increase of 33 beyond the previous year.